Replace Traefik with parachute

[mproxy](https://github.com/basecamp/parachute) is a custom minimal
proxy designed specifically for Kamal.

It has two big advantages over Traefik:
1. Imperative deployments - we tell it to switch from container A to
   container B, and it waits for container B to start then switches. No
   need to poll for health checks ourselves or mess around with forcing
   health checks to fail.
2. Support for multiple apps - as much as possible, configuration is
   supplied at runtime by the deploy command, allowing us to have
   multiple apps share an instance of mproxy without conflicting config.

.github/workflows/ci.yml

@@ -1,10 +1,25 @@
 name: CI
-on: 
+on:
   push:
     branches:
       - main
   pull_request:
 jobs:
+  rubocop:
+    name: RuboCop
+    runs-on: ubuntu-latest
+    env:
+      BUNDLE_ONLY: rubocop
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+      - name: Setup Ruby and install gems
+        uses: ruby/setup-ruby@v1
+        with:
+          ruby-version: 3.3.0
+          bundler-cache: true
+      - name: Run Rubocop
+        run: bundle exec rubocop --parallel
   tests:
     strategy:
       matrix:
@@ -12,17 +27,29 @@ jobs:
           - "2.7"
           - "3.1"
           - "3.2"
+          - "3.3"
         gemfile:
           - Gemfile
+          - gemfiles/ruby_2.7.gemfile
           - gemfiles/rails_edge.gemfile
-        continue-on-error: [false]
+        exclude:
+          - ruby-version: "2.7"
+            gemfile: Gemfile
+          - ruby-version: "2.7"
+            gemfile: gemfiles/rails_edge.gemfile
+          - ruby-version: "3.1"
+            gemfile: gemfiles/ruby_2.7.gemfile
+          - ruby-version: "3.2"
+            gemfile: gemfiles/ruby_2.7.gemfile
+          - ruby-version: "3.3"
+            gemfile: gemfiles/ruby_2.7.gemfile
     name: ${{ format('Tests (Ruby {0})', matrix.ruby-version) }}
     runs-on: ubuntu-latest
-    continue-on-error: ${{ matrix.continue-on-error }}
+    continue-on-error: true
     env:
       BUNDLE_GEMFILE: ${{ github.workspace }}/${{ matrix.gemfile }}
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
 
       - name: Install Ruby
         uses: ruby/setup-ruby@v1

.github/workflows/docker-publish.yml

@@ -1,6 +1,12 @@
 name: Docker
 
 on:
+  workflow_dispatch:
+    inputs:
+      tagInput:
+        description: 'Tag'
+        required: true
+    
   release:
     types: [created]
     tags:
@@ -29,6 +35,14 @@ jobs:
           registry: ghcr.io
           username: ${{ github.actor }}
           password: ${{ secrets.GITHUB_TOKEN }}
+      - name: Determine version tag
+        id: version-tag
+        run: |
+          INPUT_VALUE="${{ github.event.inputs.tagInput }}"
+          if [ -z "$INPUT_VALUE" ]; then
+            INPUT_VALUE="${{ github.ref_name }}"
+          fi
+          echo "::set-output name=value::$INPUT_VALUE"
       -
         name: Build and push
         uses: docker/build-push-action@v3
@@ -37,5 +51,5 @@ jobs:
           platforms: linux/amd64,linux/arm64
           push: true
           tags: |
-            ghcr.io/mrsked/mrsk:latest
+            ghcr.io/basecamp/kamal:latest
-            ghcr.io/mrsked/mrsk:${{ github.ref_name }}
+            ghcr.io/basecamp/kamal:${{ steps.version-tag.outputs.value }}

.rubocop.yml

@@ -0,0 +1,2 @@
+inherit_gem:
+  rubocop-rails-omakase: rubocop.yml

CODE_OF_CONDUCT.md

@@ -1,10 +1,10 @@
 # Contributor Code of Conduct
 
-As contributors and maintainers of the MRSK project, we pledge to create a welcoming and inclusive environment for everyone. We value the participation of each member of our community and want all contributors to feel respected and valued.
+As contributors and maintainers of the Kamal project, we pledge to create a welcoming and inclusive environment for everyone. We value the participation of each member of our community and want all contributors to feel respected and valued.
 
 We are committed to providing a harassment-free experience for everyone, regardless of gender, gender identity and expression, sexual orientation, disability, physical appearance, body size, race, age, or religion (or lack thereof). We do not tolerate harassment of participants in any form.
 
-This code of conduct applies to all MRSK project spaces, including but not limited to project code, issue trackers, chat rooms, and mailing lists. Violations of this code of conduct may result in removal from the project community.
+This code of conduct applies to all Kamal project spaces, including but not limited to project code, issue trackers, chat rooms, and mailing lists. Violations of this code of conduct may result in removal from the project community.
 
 ## Our standards
 

CONTRIBUTING.md

@@ -1,18 +1,18 @@
-# Contributing to MRSK development
+# Contributing to Kamal development
 
-Thank you for considering contributing to MRSK! This document outlines some guidelines for contributing to this open source project.
+Thank you for considering contributing to Kamal! This document outlines some guidelines for contributing to this open source project.
 
-Please make sure to review our [Code of Conduct](CODE_OF_CONDUCT.md) before contributing to MRSK.
+Please make sure to review our [Code of Conduct](CODE_OF_CONDUCT.md) before contributing to Kamal.
 
 There are several ways you can contribute to the betterment of the project:
 
-- **Report an issue?** - If the issue isn’t reported, we can’t fix it. Please report any bugs, feature, and/or improvement requests on the [MRSK GitHub Issues tracker](https://github.com/mrsked/mrsk/issues).
+- **Report an issue?** - If the issue isn’t reported, we can’t fix it. Please report any bugs, feature, and/or improvement requests on the [Kamal GitHub Issues tracker](https://github.com/basecamp/kamal/issues).
-- **Submit patches** - Do you have a new feature or a fix you'd like to share? [Submit a pull request](https://github.com/mrsked/mrsk/pulls)!
+- **Submit patches** - Do you have a new feature or a fix you'd like to share? [Submit a pull request](https://github.com/basecamp/kamal/pulls)!
-- **Write blog articles** - Are you using MRSK? We'd love to hear how you're using it with your projects. Write a tutorial and post it on your blog!
+- **Write blog articles** - Are you using Kamal? We'd love to hear how you're using it with your projects. Write a tutorial and post it on your blog!
 
 ## Issues
 
-If you encounter any issues with the project, please check the [existing issues](https://github.com/mrsked/mrsk/issues) first to see if the issue has already been reported. If the issue hasn't been reported, please open a new issue with a clear description of the problem and steps to reproduce it.
+If you encounter any issues with the project, please check the [existing issues](https://github.com/basecamp/kamal/issues) first to see if the issue has already been reported. If the issue hasn't been reported, please open a new issue with a clear description of the problem and steps to reproduce it.
 
 ## Pull Requests
 
@@ -33,17 +33,17 @@ A good commit message should describe what changed and why.
 
 ## Development
 
-The `main` branch is regularly built and tested, but it is not guaranteed to be completely stable. Tags are created regularly from release branches to indicate new official, stable release versions of MRSK.
+The `main` branch is regularly built and tested, but it is not guaranteed to be completely stable. Tags are created regularly from release branches to indicate new official, stable release versions of Kamal.
 
-MRSK is written in Ruby. You should have Ruby 3.2+ installed on your machine in order to work on MRSK. If that's already setup, run `bundle` in the root directory to install all dependencies. Then you can run `bin/test` to run all tests.
+Kamal is written in Ruby. You should have Ruby 3.2+ installed on your machine in order to work on Kamal. If that's already setup, run `bundle` in the root directory to install all dependencies. Then you can run `bin/test` to run all tests.
 
 1. Fork the project repository.
 2. Create a new branch for your contribution.
 3. Write your code or make the desired changes.
 4. **Ensure that your code passes the project's minitests by running ./bin/test.**
 5. Commit your changes and push them to your forked repository.
-6. [Open a pull request](https://github.com/mrsked/mrsk/pulls) to the main project repository with a detailed description of your changes.
+6. [Open a pull request](https://github.com/basecamp/kamal/pulls) to the main project repository with a detailed description of your changes.
 
 ## License
 
-MRSK is released under the MIT License. By contributing to this project, you agree to license your contributions under the same license.
+Kamal is released under the MIT License. By contributing to this project, you agree to license your contributions under the same license.

Dockerfile

@@ -4,14 +4,14 @@ FROM ruby:3.2.0-alpine
 # Install  docker/buildx-bin
 COPY --from=docker/buildx-bin /buildx /usr/libexec/docker/cli-plugins/docker-buildx
 
-# Set the working directory to /mrsk
+# Set the working directory to /kamal
-WORKDIR /mrsk
+WORKDIR /kamal
 
 # Copy the Gemfile, Gemfile.lock into the container
-COPY Gemfile Gemfile.lock mrsk.gemspec ./
+COPY Gemfile Gemfile.lock kamal.gemspec ./
 
-# Required in mrsk.gemspec
+# Required in kamal.gemspec
-COPY lib/mrsk/version.rb /mrsk/lib/mrsk/version.rb
+COPY lib/kamal/version.rb /kamal/lib/kamal/version.rb
 
 # Install system dependencies
 RUN apk add --no-cache --update build-base git docker openrc openssh-client-default \
@@ -25,8 +25,8 @@ RUN apk add --no-cache --update build-base git docker openrc openssh-client-defa
 COPY . .
 
 # Install the gem locally from the project folder
-RUN gem build mrsk.gemspec && \
+RUN gem build kamal.gemspec && \
-    gem install ./mrsk-*.gem --no-document
+    gem install ./kamal-*.gem --no-document
 
 # Set the working directory to /workdir
 WORKDIR /workdir
@@ -36,5 +36,5 @@ WORKDIR /workdir
 RUN git config --global --add safe.directory /workdir
 
 # Set the entrypoint to run the installed binary in /workdir
-# Example:  docker run -it -v "$PWD:/workdir" mrsk init
+# Example:  docker run -it -v "$PWD:/workdir" kamal init
-ENTRYPOINT ["mrsk"]
+ENTRYPOINT ["kamal"]

Gemfile

@@ -1,4 +1,8 @@
-source 'https://rubygems.org'
+source "https://rubygems.org"
 git_source(:github) { |repo| "https://github.com/#{repo}.git" }
 
 gemspec
+
+group :rubocop do
+  gem "rubocop-rails-omakase", require: false
+end

Gemfile.lock

@@ -1,95 +1,171 @@
 PATH
   remote: .
   specs:
-    mrsk (0.15.1)
+    kamal (1.5.2)
       activesupport (>= 7.0)
+      base64 (~> 0.2)
       bcrypt_pbkdf (~> 1.0)
+      concurrent-ruby (~> 1.2)
       dotenv (~> 2.8)
       ed25519 (~> 1.2)
       net-ssh (~> 7.0)
-      sshkit (~> 1.21)
+      sshkit (>= 1.22.2, < 2.0)
       thor (~> 1.2)
       zeitwerk (~> 2.5)
 
 GEM
   remote: https://rubygems.org/
   specs:
-    actionpack (7.0.4.3)
+    actionpack (7.1.2)
-      actionview (= 7.0.4.3)
+      actionview (= 7.1.2)
-      activesupport (= 7.0.4.3)
+      activesupport (= 7.1.2)
-      rack (~> 2.0, >= 2.2.0)
+      nokogiri (>= 1.8.5)
+      racc
+      rack (>= 2.2.4)
+      rack-session (>= 1.0.1)
       rack-test (>= 0.6.3)
-      rails-dom-testing (~> 2.0)
+      rails-dom-testing (~> 2.2)
-      rails-html-sanitizer (~> 1.0, >= 1.2.0)
+      rails-html-sanitizer (~> 1.6)
-    actionview (7.0.4.3)
+    actionview (7.1.2)
-      activesupport (= 7.0.4.3)
+      activesupport (= 7.1.2)
       builder (~> 3.1)
-      erubi (~> 1.4)
+      erubi (~> 1.11)
-      rails-dom-testing (~> 2.0)
+      rails-dom-testing (~> 2.2)
-      rails-html-sanitizer (~> 1.1, >= 1.2.0)
+      rails-html-sanitizer (~> 1.6)
-    activesupport (7.0.4.3)
+    activesupport (7.1.2)
+      base64
+      bigdecimal
       concurrent-ruby (~> 1.0, >= 1.0.2)
+      connection_pool (>= 2.2.5)
+      drb
       i18n (>= 1.6, < 2)
       minitest (>= 5.1)
+      mutex_m
       tzinfo (~> 2.0)
+    ast (2.4.2)
+    base64 (0.2.0)
     bcrypt_pbkdf (1.1.0)
+    bigdecimal (3.1.5)
     builder (3.2.4)
     concurrent-ruby (1.2.2)
+    connection_pool (2.4.1)
     crass (1.0.6)
-    debug (1.7.2)
+    debug (1.9.1)
-      irb (>= 1.5.0)
+      irb (~> 1.10)
-      reline (>= 0.3.1)
+      reline (>= 0.3.8)
     dotenv (2.8.1)
+    drb (2.2.0)
+      ruby2_keywords
     ed25519 (1.3.0)
     erubi (1.12.0)
-    i18n (1.12.0)
+    i18n (1.14.1)
       concurrent-ruby (~> 1.0)
-    io-console (0.6.0)
+    io-console (0.7.1)
-    irb (1.6.3)
+    irb (1.11.0)
-      reline (>= 0.3.0)
+      rdoc
-    loofah (2.20.0)
+      reline (>= 0.3.8)
+    json (2.7.1)
+    language_server-protocol (3.17.0.3)
+    loofah (2.22.0)
       crass (~> 1.0.2)
-      nokogiri (>= 1.5.9)
+      nokogiri (>= 1.12.0)
-    method_source (1.0.0)
+    minitest (5.20.0)
-    minitest (5.18.0)
+    mocha (2.1.0)
-    mocha (2.0.2)
       ruby2_keywords (>= 0.0.5)
+    mutex_m (0.2.0)
     net-scp (4.0.0)
       net-ssh (>= 2.6.5, < 8.0.0)
-    net-ssh (7.1.0)
+    net-sftp (4.0.0)
-    nokogiri (1.14.2-arm64-darwin)
+      net-ssh (>= 5.0.0, < 8.0.0)
+    net-ssh (7.2.1)
+    nokogiri (1.16.0-arm64-darwin)
       racc (~> 1.4)
-    nokogiri (1.14.2-x86_64-darwin)
+    nokogiri (1.16.0-x86_64-darwin)
       racc (~> 1.4)
-    nokogiri (1.14.2-x86_64-linux)
+    nokogiri (1.16.0-x86_64-linux)
       racc (~> 1.4)
-    racc (1.6.2)
+    parallel (1.24.0)
-    rack (2.2.6.4)
+    parser (3.3.0.5)
+      ast (~> 2.4.1)
+      racc
+    psych (5.1.2)
+      stringio
+    racc (1.7.3)
+    rack (3.0.8)
+    rack-session (2.0.0)
+      rack (>= 3.0.0)
     rack-test (2.1.0)
       rack (>= 1.3)
-    rails-dom-testing (2.0.3)
+    rackup (2.1.0)
-      activesupport (>= 4.2.0)
+      rack (>= 3)
+      webrick (~> 1.8)
+    rails-dom-testing (2.2.0)
+      activesupport (>= 5.0.0)
+      minitest
       nokogiri (>= 1.6)
-    rails-html-sanitizer (1.5.0)
+    rails-html-sanitizer (1.6.0)
-      loofah (~> 2.19, >= 2.19.1)
+      loofah (~> 2.21)
-    railties (7.0.4.3)
+      nokogiri (~> 1.14)
-      actionpack (= 7.0.4.3)
+    railties (7.1.2)
-      activesupport (= 7.0.4.3)
+      actionpack (= 7.1.2)
-      method_source
+      activesupport (= 7.1.2)
+      irb
+      rackup (>= 1.0.0)
       rake (>= 12.2)
-      thor (~> 1.0)
+      thor (~> 1.0, >= 1.2.2)
-      zeitwerk (~> 2.5)
+      zeitwerk (~> 2.6)
-    rake (13.0.6)
+    rainbow (3.1.1)
-    reline (0.3.3)
+    rake (13.1.0)
+    rdoc (6.6.2)
+      psych (>= 4.0.0)
+    regexp_parser (2.9.0)
+    reline (0.4.2)
       io-console (~> 0.5)
+    rexml (3.2.6)
+    rubocop (1.62.1)
+      json (~> 2.3)
+      language_server-protocol (>= 3.17.0)
+      parallel (~> 1.10)
+      parser (>= 3.3.0.2)
+      rainbow (>= 2.2.2, < 4.0)
+      regexp_parser (>= 1.8, < 3.0)
+      rexml (>= 3.2.5, < 4.0)
+      rubocop-ast (>= 1.31.1, < 2.0)
+      ruby-progressbar (~> 1.7)
+      unicode-display_width (>= 2.4.0, < 3.0)
+    rubocop-ast (1.31.2)
+      parser (>= 3.3.0.4)
+    rubocop-minitest (0.35.0)
+      rubocop (>= 1.61, < 2.0)
+      rubocop-ast (>= 1.31.1, < 2.0)
+    rubocop-performance (1.20.2)
+      rubocop (>= 1.48.1, < 2.0)
+      rubocop-ast (>= 1.30.0, < 2.0)
+    rubocop-rails (2.24.0)
+      activesupport (>= 4.2.0)
+      rack (>= 1.1)
+      rubocop (>= 1.33.0, < 2.0)
+      rubocop-ast (>= 1.31.1, < 2.0)
+    rubocop-rails-omakase (1.0.0)
+      rubocop
+      rubocop-minitest
+      rubocop-performance
+      rubocop-rails
+    ruby-progressbar (1.13.0)
     ruby2_keywords (0.0.5)
-    sshkit (1.21.4)
+    sshkit (1.22.2)
+      base64
+      mutex_m
       net-scp (>= 1.1.2)
+      net-sftp (>= 2.1.2)
       net-ssh (>= 2.8.0)
-    thor (1.2.1)
+    stringio (3.1.0)
+    thor (1.3.0)
     tzinfo (2.0.6)
       concurrent-ruby (~> 1.0)
-    zeitwerk (2.6.7)
+    unicode-display_width (2.5.0)
+    webrick (1.8.1)
+    zeitwerk (2.6.12)
 
 PLATFORMS
   arm64-darwin
@@ -98,9 +174,10 @@ PLATFORMS
 
 DEPENDENCIES
   debug
+  kamal!
   mocha
-  mrsk!
   railties
+  rubocop-rails-omakase
 
 BUNDLED WITH
    2.4.3

bin/kamal

@@ -3,10 +3,10 @@
 # Prevent failures from being reported twice.
 Thread.report_on_exception = false
 
-require "mrsk"
+require "kamal"
 
 begin
-  Mrsk::Cli::Main.start(ARGV)
+  Kamal::Cli::Main.start(ARGV)
 rescue SSHKit::Runner::ExecuteError => e
   puts "  \e[31mERROR (#{e.cause.class}): #{e.message}\e[0m"
   puts e.cause.backtrace if ENV["VERBOSE"]

bin/release

@@ -2,13 +2,13 @@
 
 VERSION=$1
 
-printf "module Mrsk\n  VERSION = \"$VERSION\"\nend\n" > ./lib/mrsk/version.rb
+printf "module Kamal\n  VERSION = \"$VERSION\"\nend\n" > ./lib/kamal/version.rb
 bundle
-git add Gemfile.lock lib/mrsk/version.rb
+git add Gemfile.lock lib/kamal/version.rb
 git commit -m "Bump version for $VERSION"
 git push
 git tag v$VERSION
 git push --tags
-gem build mrsk.gemspec
+gem build kamal.gemspec
-gem push "mrsk-$VERSION.gem" --host https://rubygems.org
+gem push "kamal-$VERSION.gem" --host https://rubygems.org
-rm "mrsk-$VERSION.gem"
+rm "kamal-$VERSION.gem"

gemfiles/ruby_2.7.gemfile

@@ -0,0 +1,6 @@
+source 'https://rubygems.org'
+git_source(:github) { |repo| "https://github.com/#{repo}.git" }
+
+gemspec path: "../"
+
+gem "nokogiri", "~> 1.15.0"

kamal.gemspec

@@ -1,25 +1,26 @@
-require_relative "lib/mrsk/version"
+require_relative "lib/kamal/version"
 
 Gem::Specification.new do |spec|
-  spec.name        = "mrsk"
+  spec.name        = "kamal"
-  spec.version     = Mrsk::VERSION
+  spec.version     = Kamal::VERSION
   spec.authors     = [ "David Heinemeier Hansson" ]
   spec.email       = "dhh@hey.com"
-  spec.homepage    = "https://github.com/rails/mrsk"
+  spec.homepage    = "https://github.com/basecamp/kamal"
   spec.summary     = "Deploy web apps in containers to servers running Docker with zero downtime."
   spec.license     = "MIT"
-
   spec.files = Dir["lib/**/*", "MIT-LICENSE", "README.md"]
-  spec.executables = %w[ mrsk ]
+  spec.executables = %w[ kamal ]
 
   spec.add_dependency "activesupport", ">= 7.0"
-  spec.add_dependency "sshkit", "~> 1.21"
+  spec.add_dependency "sshkit", ">= 1.22.2", "< 2.0"
   spec.add_dependency "net-ssh", "~> 7.0"
   spec.add_dependency "thor", "~> 1.2"
   spec.add_dependency "dotenv", "~> 2.8"
   spec.add_dependency "zeitwerk", "~> 2.5"
   spec.add_dependency "ed25519", "~> 1.2"
   spec.add_dependency "bcrypt_pbkdf", "~> 1.0"
+  spec.add_dependency "concurrent-ruby", "~> 1.2"
+  spec.add_dependency "base64", "~> 0.2"
 
   spec.add_development_dependency "debug"
   spec.add_development_dependency "mocha"

lib/kamal.rb

@@ -1,10 +1,10 @@
-module Mrsk
+module Kamal
 end
 
 require "active_support"
 require "zeitwerk"
 
 loader = Zeitwerk::Loader.for_gem
-loader.ignore("#{__dir__}/mrsk/sshkit_with_ext.rb")
+loader.ignore(File.join(__dir__, "kamal", "sshkit_with_ext.rb"))
 loader.setup
 loader.eager_load # We need all commands loaded.

lib/kamal/cli.rb

@@ -1,7 +1,8 @@
-module Mrsk::Cli
+module Kamal::Cli
   class LockError < StandardError; end
   class HookError < StandardError; end
+  class BootError < StandardError; end
 end
 
 # SSHKit uses instance eval, so we need a global const for ergonomics
-MRSK = Mrsk::Commander.new
+KAMAL = Kamal::Commander.new

lib/kamal/cli/accessory.rb

@@ -1,17 +1,17 @@
-class Mrsk::Cli::Accessory < Mrsk::Cli::Base
+class Kamal::Cli::Accessory < Kamal::Cli::Base
   desc "boot [NAME]", "Boot new accessory service on host (use NAME=all to boot all accessories)"
   def boot(name, login: true)
-    mutating do
+    with_lock do
       if name == "all"
-        MRSK.accessory_names.each { |accessory_name| boot(accessory_name) }
+        KAMAL.accessory_names.each { |accessory_name| boot(accessory_name) }
       else
-        with_accessory(name) do |accessory|
+        with_accessory(name) do |accessory, hosts|
           directories(name)
           upload(name)
 
-          on(accessory.hosts) do
+          on(hosts) do
-            execute *MRSK.registry.login if login
+            execute *KAMAL.registry.login if login
-            execute *MRSK.auditor.record("Booted #{name} accessory"), verbosity: :debug
+            execute *KAMAL.auditor.record("Booted #{name} accessory"), verbosity: :debug
             execute *accessory.run
           end
         end
@@ -21,9 +21,9 @@ class Mrsk::Cli::Accessory < Mrsk::Cli::Base
 
   desc "upload [NAME]", "Upload accessory files to host", hide: true
   def upload(name)
-    mutating do
+    with_lock do
-      with_accessory(name) do |accessory|
+      with_accessory(name) do |accessory, hosts|
-        on(accessory.hosts) do
+        on(hosts) do
           accessory.files.each do |(local, remote)|
             accessory.ensure_local_file_present(local)
 
@@ -38,9 +38,9 @@ class Mrsk::Cli::Accessory < Mrsk::Cli::Base
 
   desc "directories [NAME]", "Create accessory directories on host", hide: true
   def directories(name)
-    mutating do
+    with_lock do
-      with_accessory(name) do |accessory|
+      with_accessory(name) do |accessory, hosts|
-        on(accessory.hosts) do
+        on(hosts) do
           accessory.directories.keys.each do |host_path|
             execute *accessory.make_directory(host_path)
           end
@@ -49,27 +49,31 @@ class Mrsk::Cli::Accessory < Mrsk::Cli::Base
     end
   end
 
-  desc "reboot [NAME]", "Reboot existing accessory on host (stop container, remove container, start new container)"
+  desc "reboot [NAME]", "Reboot existing accessory on host (stop container, remove container, start new container; use NAME=all to boot all accessories)"
   def reboot(name)
-    mutating do
+    with_lock do
-      with_accessory(name) do |accessory|
+      if name == "all"
-        on(accessory.hosts) do
+        KAMAL.accessory_names.each { |accessory_name| reboot(accessory_name) }
-          execute *MRSK.registry.login
+      else
-        end
+        with_accessory(name) do |accessory, hosts|
+          on(hosts) do
+            execute *KAMAL.registry.login
+          end
 
-        stop(name)
+          stop(name)
-        remove_container(name)
+          remove_container(name)
-        boot(name, login: false)
+          boot(name, login: false)
+        end
       end
     end
   end
 
   desc "start [NAME]", "Start existing accessory container on host"
   def start(name)
-    mutating do
+    with_lock do
-      with_accessory(name) do |accessory|
+      with_accessory(name) do |accessory, hosts|
-        on(accessory.hosts) do
+        on(hosts) do
-          execute *MRSK.auditor.record("Started #{name} accessory"), verbosity: :debug
+          execute *KAMAL.auditor.record("Started #{name} accessory"), verbosity: :debug
           execute *accessory.start
         end
       end
@@ -78,10 +82,10 @@ class Mrsk::Cli::Accessory < Mrsk::Cli::Base
 
   desc "stop [NAME]", "Stop existing accessory container on host"
   def stop(name)
-    mutating do
+    with_lock do
-      with_accessory(name) do |accessory|
+      with_accessory(name) do |accessory, hosts|
-        on(accessory.hosts) do
+        on(hosts) do
-          execute *MRSK.auditor.record("Stopped #{name} accessory"), verbosity: :debug
+          execute *KAMAL.auditor.record("Stopped #{name} accessory"), verbosity: :debug
           execute *accessory.stop, raise_on_non_zero_exit: false
         end
       end
@@ -90,7 +94,7 @@ class Mrsk::Cli::Accessory < Mrsk::Cli::Base
 
   desc "restart [NAME]", "Restart existing accessory container on host"
   def restart(name)
-    mutating do
+    with_lock do
       with_accessory(name) do
         stop(name)
         start(name)
@@ -101,10 +105,11 @@ class Mrsk::Cli::Accessory < Mrsk::Cli::Base
   desc "details [NAME]", "Show details about accessory on host (use NAME=all to show all accessories)"
   def details(name)
     if name == "all"
-      MRSK.accessory_names.each { |accessory_name| details(accessory_name) }
+      KAMAL.accessory_names.each { |accessory_name| details(accessory_name) }
     else
-      with_accessory(name) do |accessory|
+      type = "Accessory #{name}"
-        on(accessory.hosts) { puts capture_with_info(*accessory.info) }
+      with_accessory(name) do |accessory, hosts|
+        on(hosts) { puts_by_host host, capture_with_info(*accessory.info), type: type }
       end
     end
   end
@@ -113,7 +118,7 @@ class Mrsk::Cli::Accessory < Mrsk::Cli::Base
   option :interactive, aliases: "-i", type: :boolean, default: false, desc: "Execute command over ssh for an interactive shell (use for console/bash)"
   option :reuse, type: :boolean, default: false, desc: "Reuse currently running container instead of starting a new one"
   def exec(name, cmd)
-    with_accessory(name) do |accessory|
+    with_accessory(name) do |accessory, hosts|
       case
       when options[:interactive] && options[:reuse]
         say "Launching interactive command with via SSH from existing container...", :magenta
@@ -125,15 +130,15 @@ class Mrsk::Cli::Accessory < Mrsk::Cli::Base
 
       when options[:reuse]
         say "Launching command from existing container...", :magenta
-        on(accessory.hosts) do
+        on(hosts) do
-          execute *MRSK.auditor.record("Executed cmd '#{cmd}' on #{name} accessory"), verbosity: :debug
+          execute *KAMAL.auditor.record("Executed cmd '#{cmd}' on #{name} accessory"), verbosity: :debug
           capture_with_info(*accessory.execute_in_existing_container(cmd))
         end
 
       else
         say "Launching command from new container...", :magenta
-        on(accessory.hosts) do
+        on(hosts) do
-          execute *MRSK.auditor.record("Executed cmd '#{cmd}' on #{name} accessory"), verbosity: :debug
+          execute *KAMAL.auditor.record("Executed cmd '#{cmd}' on #{name} accessory"), verbosity: :debug
           capture_with_info(*accessory.execute_in_new_container(cmd))
         end
       end
@@ -146,12 +151,12 @@ class Mrsk::Cli::Accessory < Mrsk::Cli::Base
   option :grep, aliases: "-g", desc: "Show lines with grep match only (use this to fetch specific requests by id)"
   option :follow, aliases: "-f", desc: "Follow logs on primary server (or specific host set by --hosts)"
   def logs(name)
-    with_accessory(name) do |accessory|
+    with_accessory(name) do |accessory, hosts|
       grep = options[:grep]
 
       if options[:follow]
         run_locally do
-          info "Following logs on #{accessory.hosts}..."
+          info "Following logs on #{hosts}..."
           info accessory.follow_logs(grep: grep)
           exec accessory.follow_logs(grep: grep)
         end
@@ -159,7 +164,7 @@ class Mrsk::Cli::Accessory < Mrsk::Cli::Base
         since = options[:since]
         lines = options[:lines].presence || ((since || grep) ? nil : 100) # Default to 100 lines if since or grep isn't set
 
-        on(accessory.hosts) do
+        on(hosts) do
           puts capture_with_info(*accessory.logs(since: since, lines: lines, grep: grep))
         end
       end
@@ -169,17 +174,12 @@ class Mrsk::Cli::Accessory < Mrsk::Cli::Base
   desc "remove [NAME]", "Remove accessory container, image and data directory from host (use NAME=all to remove all accessories)"
   option :confirmed, aliases: "-y", type: :boolean, default: false, desc: "Proceed without confirmation question"
   def remove(name)
-    mutating do
+    confirming "This will remove all containers, images and data directories for #{name}. Are you sure?" do
-      if name == "all"
+      with_lock do
-        MRSK.accessory_names.each { |accessory_name| remove(accessory_name) }
+        if name == "all"
-      else
+          KAMAL.accessory_names.each { |accessory_name| remove_accessory(accessory_name) }
-        if options[:confirmed] || ask("This will remove all containers, images and data directories for #{name}. Are you sure?", limited_to: %w( y N ), default: "N") == "y"
+        else
-          with_accessory(name) do
+          remove_accessory(name)
-            stop(name)
-            remove_container(name)
-            remove_image(name)
-            remove_service_directory(name)
-          end
         end
       end
     end
@@ -187,10 +187,10 @@ class Mrsk::Cli::Accessory < Mrsk::Cli::Base
 
   desc "remove_container [NAME]", "Remove accessory container from host", hide: true
   def remove_container(name)
-    mutating do
+    with_lock do
-      with_accessory(name) do |accessory|
+      with_accessory(name) do |accessory, hosts|
-        on(accessory.hosts) do
+        on(hosts) do
-          execute *MRSK.auditor.record("Remove #{name} accessory container"), verbosity: :debug
+          execute *KAMAL.auditor.record("Remove #{name} accessory container"), verbosity: :debug
           execute *accessory.remove_container
         end
       end
@@ -199,10 +199,10 @@ class Mrsk::Cli::Accessory < Mrsk::Cli::Base
 
   desc "remove_image [NAME]", "Remove accessory image from host", hide: true
   def remove_image(name)
-    mutating do
+    with_lock do
-      with_accessory(name) do |accessory|
+      with_accessory(name) do |accessory, hosts|
-        on(accessory.hosts) do
+        on(hosts) do
-          execute *MRSK.auditor.record("Removed #{name} accessory image"), verbosity: :debug
+          execute *KAMAL.auditor.record("Removed #{name} accessory image"), verbosity: :debug
           execute *accessory.remove_image
         end
       end
@@ -211,9 +211,9 @@ class Mrsk::Cli::Accessory < Mrsk::Cli::Base
 
   desc "remove_service_directory [NAME]", "Remove accessory directory used for uploaded files and data directories from host", hide: true
   def remove_service_directory(name)
-    mutating do
+    with_lock do
-      with_accessory(name) do |accessory|
+      with_accessory(name) do |accessory, hosts|
-        on(accessory.hosts) do
+        on(hosts) do
           execute *accessory.remove_service_directory
         end
       end
@@ -222,18 +222,36 @@ class Mrsk::Cli::Accessory < Mrsk::Cli::Base
 
   private
     def with_accessory(name)
-      if accessory = MRSK.accessory(name)
+      if KAMAL.config.accessory(name)
-        yield accessory
+        accessory = KAMAL.accessory(name)
+        yield accessory, accessory_hosts(accessory)
       else
         error_on_missing_accessory(name)
       end
     end
 
     def error_on_missing_accessory(name)
-      options = MRSK.accessory_names.presence
+      options = KAMAL.accessory_names.presence
 
       error \
         "No accessory by the name of '#{name}'" +
         (options ? " (options: #{options.to_sentence})" : "")
     end
+
+    def accessory_hosts(accessory)
+      if KAMAL.specific_hosts&.any?
+        KAMAL.specific_hosts & accessory.hosts
+      else
+        accessory.hosts
+      end
+    end
+
+    def remove_accessory(name)
+      with_accessory(name) do
+        stop(name)
+        remove_container(name)
+        remove_image(name)
+        remove_service_directory(name)
+      end
+    end
 end

lib/kamal/cli/app.rb

@@ -0,0 +1,315 @@
+class Kamal::Cli::App < Kamal::Cli::Base
+  desc "boot", "Boot app on servers (or reboot app if already running)"
+  def boot
+    with_lock do
+      say "Get most recent version available as an image...", :magenta unless options[:version]
+      using_version(version_or_latest) do |version|
+        say "Start container with version #{version} using a #{KAMAL.config.readiness_delay}s readiness delay (or reboot if already running)...", :magenta
+
+        # Assets are prepared in a separate step to ensure they are on all hosts before booting
+        on(KAMAL.hosts) do
+          KAMAL.roles_on(host).each do |role|
+            PrepareAssets.new(host, role, self).run
+          end
+        end
+
+        # Primary hosts and roles are returned first, so they can open the barrier
+        barrier = Barrier.new if KAMAL.roles.many?
+
+        on(KAMAL.hosts, **KAMAL.boot_strategy) do |host|
+          KAMAL.roles_on(host).each do |role|
+            Boot.new(host, role, self, version, barrier).run
+          end
+        end
+
+        # Tag once the app booted on all hosts
+        on(KAMAL.hosts) do |host|
+          execute *KAMAL.auditor.record("Tagging #{KAMAL.config.absolute_image} as the latest image"), verbosity: :debug
+          execute *KAMAL.app.tag_latest_image
+        end
+      end
+    end
+  end
+
+  desc "start", "Start existing app container on servers"
+  def start
+    with_lock do
+      on(KAMAL.hosts) do |host|
+        roles = KAMAL.roles_on(host)
+
+        roles.each do |role|
+          app = KAMAL.app(role: role, host: host)
+          execute *KAMAL.auditor.record("Started app version #{KAMAL.config.version}"), verbosity: :debug
+          execute *app.start, raise_on_non_zero_exit: false
+
+          if role.running_proxy?
+            version = capture_with_info(*app.current_running_version, raise_on_non_zero_exit: false).strip
+            endpoint = capture_with_info(*app.container_endpoint(version: version)).strip
+            raise Kamal::Cli::BootError, "Failed to get endpoint for #{role} on #{host}, did the container boot?" if endpoint.empty?
+
+            execute *KAMAL.proxy.deploy(role.container_prefix, target: endpoint)
+          end
+        end
+      end
+    end
+  end
+
+  desc "stop", "Stop app container on servers"
+  def stop
+    with_lock do
+      on(KAMAL.hosts) do |host|
+        roles = KAMAL.roles_on(host)
+
+        roles.each do |role|
+          app = KAMAL.app(role: role, host: host)
+          version = capture_with_info(*app.current_running_version, raise_on_non_zero_exit: false).strip
+
+          execute *KAMAL.auditor.record("Stopped app", role: role), verbosity: :debug
+
+          if role.running_proxy?
+            endpoint = capture_with_info(*app.container_endpoint(version: version)).strip
+            if endpoint.present?
+              execute *KAMAL.proxy.remove(role.container_prefix, target: endpoint), raise_on_non_zero_exit: false
+            end
+          end
+
+          execute *app.stop, raise_on_non_zero_exit: false
+        end
+      end
+    end
+  end
+
+  # FIXME: Drop in favor of just containers?
+  desc "details", "Show details about app containers"
+  def details
+    on(KAMAL.hosts) do |host|
+      roles = KAMAL.roles_on(host)
+
+      roles.each do |role|
+        puts_by_host host, capture_with_info(*KAMAL.app(role: role, host: host).info)
+      end
+    end
+  end
+
+  desc "exec [CMD]", "Execute a custom command on servers within the app container (use --help to show options)"
+  option :interactive, aliases: "-i", type: :boolean, default: false, desc: "Execute command over ssh for an interactive shell (use for console/bash)"
+  option :reuse, type: :boolean, default: false, desc: "Reuse currently running container instead of starting a new one"
+  option :env, aliases: "-e", type: :hash, desc: "Set environment variables for the command"
+  def exec(cmd)
+    env = options[:env]
+    case
+    when options[:interactive] && options[:reuse]
+      say "Get current version of running container...", :magenta unless options[:version]
+      using_version(options[:version] || current_running_version) do |version|
+        say "Launching interactive command with version #{version} via SSH from existing container on #{KAMAL.primary_host}...", :magenta
+        run_locally { exec KAMAL.app(role: KAMAL.primary_role, host: KAMAL.primary_host).execute_in_existing_container_over_ssh(cmd, env: env) }
+      end
+
+    when options[:interactive]
+      say "Get most recent version available as an image...", :magenta unless options[:version]
+      using_version(version_or_latest) do |version|
+        say "Launching interactive command with version #{version} via SSH from new container on #{KAMAL.primary_host}...", :magenta
+        run_locally do
+          exec KAMAL.app(role: KAMAL.primary_role, host: KAMAL.primary_host).execute_in_new_container_over_ssh(cmd, env: env)
+        end
+      end
+
+    when options[:reuse]
+      say "Get current version of running container...", :magenta unless options[:version]
+      using_version(options[:version] || current_running_version) do |version|
+        say "Launching command with version #{version} from existing container...", :magenta
+
+        on(KAMAL.hosts) do |host|
+          roles = KAMAL.roles_on(host)
+
+          roles.each do |role|
+            execute *KAMAL.auditor.record("Executed cmd '#{cmd}' on app version #{version}", role: role), verbosity: :debug
+            puts_by_host host, capture_with_info(*KAMAL.app(role: role, host: host).execute_in_existing_container(cmd, env: env))
+          end
+        end
+      end
+
+    else
+      say "Get most recent version available as an image...", :magenta unless options[:version]
+      using_version(version_or_latest) do |version|
+        say "Launching command with version #{version} from new container...", :magenta
+        on(KAMAL.hosts) do |host|
+          roles = KAMAL.roles_on(host)
+
+          roles.each do |role|
+            execute *KAMAL.auditor.record("Executed cmd '#{cmd}' on app version #{version}"), verbosity: :debug
+            puts_by_host host, capture_with_info(*KAMAL.app(role: role, host: host).execute_in_new_container(cmd, env: env))
+          end
+        end
+      end
+    end
+  end
+
+  desc "containers", "Show app containers on servers"
+  def containers
+    on(KAMAL.hosts) { |host| puts_by_host host, capture_with_info(*KAMAL.app.list_containers) }
+  end
+
+  desc "stale_containers", "Detect app stale containers"
+  option :stop, aliases: "-s", type: :boolean, default: false, desc: "Stop the stale containers found"
+  def stale_containers
+    stop = options[:stop]
+
+    with_lock_if_stopping do
+      on(KAMAL.hosts) do |host|
+        roles = KAMAL.roles_on(host)
+
+        roles.each do |role|
+          app = KAMAL.app(role: role, host: host)
+          versions = capture_with_info(*app.list_versions, raise_on_non_zero_exit: false).split("\n")
+          versions -= [ capture_with_info(*app.current_running_version, raise_on_non_zero_exit: false).strip ]
+
+          versions.each do |version|
+            if stop
+              puts_by_host host, "Stopping stale container for role #{role} with version #{version}"
+              execute *app.stop(version: version), raise_on_non_zero_exit: false
+            else
+              puts_by_host host,  "Detected stale container for role #{role} with version #{version} (use `kamal app stale_containers --stop` to stop)"
+            end
+          end
+        end
+      end
+    end
+  end
+
+  desc "images", "Show app images on servers"
+  def images
+    on(KAMAL.hosts) { |host| puts_by_host host, capture_with_info(*KAMAL.app.list_images) }
+  end
+
+  desc "logs", "Show log lines from app on servers (use --help to show options)"
+  option :since, aliases: "-s", desc: "Show lines since timestamp (e.g. 2013-01-02T13:23:37Z) or relative (e.g. 42m for 42 minutes)"
+  option :lines, type: :numeric, aliases: "-n", desc: "Number of lines to show from each server"
+  option :grep, aliases: "-g", desc: "Show lines with grep match only (use this to fetch specific requests by id)"
+  option :follow, aliases: "-f", desc: "Follow log on primary server (or specific host set by --hosts)"
+  def logs
+    # FIXME: Catch when app containers aren't running
+
+    grep = options[:grep]
+    since = options[:since]
+    if options[:follow]
+      lines = options[:lines].presence || ((since || grep) ? nil : 10) # Default to 10 lines if since or grep isn't set
+
+      run_locally do
+        info "Following logs on #{KAMAL.primary_host}..."
+
+        KAMAL.specific_roles ||= [ "web" ]
+        role = KAMAL.roles_on(KAMAL.primary_host).first
+
+        app = KAMAL.app(role: role, host: host)
+        info app.follow_logs(host: KAMAL.primary_host, lines: lines, grep: grep)
+        exec app.follow_logs(host: KAMAL.primary_host, lines: lines, grep: grep)
+      end
+    else
+      lines = options[:lines].presence || ((since || grep) ? nil : 100) # Default to 100 lines if since or grep isn't set
+
+      on(KAMAL.hosts) do |host|
+        roles = KAMAL.roles_on(host)
+
+        roles.each do |role|
+          begin
+            puts_by_host host, capture_with_info(*KAMAL.app(role: role, host: host).logs(since: since, lines: lines, grep: grep))
+          rescue SSHKit::Command::Failed
+            puts_by_host host, "Nothing found"
+          end
+        end
+      end
+    end
+  end
+
+  desc "remove", "Remove app containers and images from servers"
+  def remove
+    with_lock do
+      stop
+      remove_containers
+      remove_images
+    end
+  end
+
+  desc "remove_container [VERSION]", "Remove app container with given version from servers", hide: true
+  def remove_container(version)
+    with_lock do
+      on(KAMAL.hosts) do |host|
+        roles = KAMAL.roles_on(host)
+
+        roles.each do |role|
+          execute *KAMAL.auditor.record("Removed app container with version #{version}", role: role), verbosity: :debug
+          execute *KAMAL.app(role: role, host: host).remove_container(version: version)
+        end
+      end
+    end
+  end
+
+  desc "remove_containers", "Remove all app containers from servers", hide: true
+  def remove_containers
+    with_lock do
+      on(KAMAL.hosts) do |host|
+        roles = KAMAL.roles_on(host)
+
+        roles.each do |role|
+          execute *KAMAL.auditor.record("Removed all app containers", role: role), verbosity: :debug
+          execute *KAMAL.app(role: role, host: host).remove_containers
+        end
+      end
+    end
+  end
+
+  desc "remove_images", "Remove all app images from servers", hide: true
+  def remove_images
+    with_lock do
+      on(KAMAL.hosts) do
+        execute *KAMAL.auditor.record("Removed all app images"), verbosity: :debug
+        execute *KAMAL.app.remove_images
+      end
+    end
+  end
+
+  desc "version", "Show app version currently running on servers"
+  def version
+    on(KAMAL.hosts) do |host|
+      role = KAMAL.roles_on(host).first
+      puts_by_host host, capture_with_info(*KAMAL.app(role: role, host: host).current_running_version).strip
+    end
+  end
+
+  private
+    def using_version(new_version)
+      if new_version
+        begin
+          old_version = KAMAL.config.version
+          KAMAL.config.version = new_version
+          yield new_version
+        ensure
+          KAMAL.config.version = old_version
+        end
+      else
+        yield KAMAL.config.version
+      end
+    end
+
+    def current_running_version(host: KAMAL.primary_host)
+      version = nil
+      on(host) do
+        role = KAMAL.roles_on(host).first
+        version = capture_with_info(*KAMAL.app(role: role, host: host).current_running_version).strip
+      end
+      version.presence
+    end
+
+    def version_or_latest
+      options[:version] || KAMAL.config.latest_tag
+    end
+
+    def with_lock_if_stopping
+      if options[:stop]
+        with_lock { yield }
+      else
+        yield
+      end
+    end
+end

lib/kamal/cli/app/barrier.rb

@@ -0,0 +1,31 @@
+class Kamal::Cli::App::Barrier
+  def initialize
+    @ivar = Concurrent::IVar.new
+  end
+
+  def close
+    set(false)
+  end
+
+  def open
+    set(true)
+  end
+
+  def wait
+    unless opened?
+      raise Kamal::Cli::BootError.new("Halted at barrier")
+    end
+  end
+
+  private
+    def opened?
+      @ivar.value
+    end
+
+    def set(value)
+      @ivar.set(value)
+      true
+    rescue Concurrent::MultipleAssignmentError
+      false
+    end
+end

lib/kamal/cli/app/boot.rb

@@ -0,0 +1,111 @@
+class Kamal::Cli::App::Boot
+  attr_reader :host, :role, :version, :barrier, :sshkit
+  delegate :execute, :capture_with_info, :capture_with_pretty_json, :info, :error, to: :sshkit
+  delegate :assets?, :running_proxy?, to: :role
+
+  def initialize(host, role, sshkit, version, barrier)
+    @host = host
+    @role = role
+    @version = version
+    @barrier = barrier
+    @sshkit = sshkit
+  end
+
+  def run
+    old_version = old_version_renamed_if_clashing
+
+    wait_at_barrier if queuer?
+
+    begin
+      start_new_version
+    rescue => e
+      close_barrier if gatekeeper?
+      stop_new_version
+      raise
+    end
+
+    release_barrier if gatekeeper?
+
+    if old_version
+      stop_old_version(old_version)
+    end
+  end
+
+  private
+    def old_version_renamed_if_clashing
+      if capture_with_info(*app.container_id_for_version(version), raise_on_non_zero_exit: false).present?
+        renamed_version = "#{version}_replaced_#{SecureRandom.hex(8)}"
+        info "Renaming container #{version} to #{renamed_version} as already deployed on #{host}"
+        audit("Renaming container #{version} to #{renamed_version}")
+        execute *app.rename_container(version: version, new_version: renamed_version)
+      end
+
+      capture_with_info(*app.current_running_version, raise_on_non_zero_exit: false).strip.presence
+    end
+
+    def start_new_version
+      audit "Booted app version #{version}"
+      hostname = "#{host.to_s[0...51].gsub(/\.+$/, '')}-#{SecureRandom.hex(6)}"
+      execute *app.run(hostname: hostname)
+      if running_proxy?
+        endpoint = capture_with_info(*app.container_endpoint(version: version)).strip
+        raise Kamal::Cli::BootError, "Failed to get endpoint for #{role} on #{host}, did the container boot?" if endpoint.empty?
+        execute *KAMAL.proxy.deploy(role.container_prefix, target: endpoint)
+      end
+    end
+
+    def stop_new_version
+      execute *app.stop(version: version), raise_on_non_zero_exit: false
+    end
+
+    def stop_old_version(version)
+      execute *app.stop(version: version), raise_on_non_zero_exit: false
+      execute *app.clean_up_assets if assets?
+    end
+
+    def release_barrier
+      if barrier.open
+        info "First #{KAMAL.primary_role} container is healthy on #{host}, booting other roles"
+      end
+    end
+
+    def wait_at_barrier
+      info "Waiting for the first healthy #{KAMAL.primary_role} container before booting #{role} on #{host}..."
+      barrier.wait
+      info "First #{KAMAL.primary_role} container is healthy, booting #{role} on #{host}..."
+    rescue Kamal::Cli::BootError
+      info "First #{KAMAL.primary_role} container is unhealthy, not booting #{role} on #{host}"
+      raise
+    end
+
+    def close_barrier
+      if barrier.close
+        info "First #{KAMAL.primary_role} container is unhealthy on #{host}, not booting other roles"
+        error capture_with_info(*app.logs(version: version))
+      end
+    end
+
+    def barrier_role?
+      role == KAMAL.primary_role
+    end
+
+    def app
+      @app ||= KAMAL.app(role: role, host: host)
+    end
+
+    def auditor
+      @auditor = KAMAL.auditor(role: role)
+    end
+
+    def audit(message)
+      execute *auditor.record(message), verbosity: :debug
+    end
+
+    def gatekeeper?
+      barrier && barrier_role?
+    end
+
+    def queuer?
+      barrier && !barrier_role?
+    end
+end

lib/kamal/cli/app/prepare_assets.rb

@@ -0,0 +1,24 @@
+class Kamal::Cli::App::PrepareAssets
+  attr_reader :host, :role, :sshkit
+  delegate :execute, :capture_with_info, :info, to: :sshkit
+  delegate :assets?, to: :role
+
+  def initialize(host, role, sshkit)
+    @host = host
+    @role = role
+    @sshkit = sshkit
+  end
+
+  def run
+    if assets?
+      execute *app.extract_assets
+      old_version = capture_with_info(*app.current_running_version, raise_on_non_zero_exit: false).strip
+      execute *app.sync_asset_volumes(old_version: old_version)
+    end
+  end
+
+  private
+    def app
+      @app ||= KAMAL.app(role: role, host: host)
+    end
+end

lib/kamal/cli/base.rb

@@ -1,8 +1,8 @@
 require "thor"
 require "dotenv"
-require "mrsk/sshkit_with_ext"
+require "kamal/sshkit_with_ext"
 
-module Mrsk::Cli
+module Kamal::Cli
   class Base < Thor
     include SSHKit::DSL
 
@@ -14,8 +14,8 @@ module Mrsk::Cli
     class_option :version, desc: "Run commands against a specific app version"
 
     class_option :primary, type: :boolean, aliases: "-p", desc: "Run commands only on primary host instead of all"
-    class_option :hosts, aliases: "-h", desc: "Run commands on these hosts instead of all (separate by comma)"
+    class_option :hosts, aliases: "-h", desc: "Run commands on these hosts instead of all (separate by comma, supports wildcards with *)"
-    class_option :roles, aliases: "-r", desc: "Run commands on these roles instead of all (separate by comma)"
+    class_option :roles, aliases: "-r", desc: "Run commands on these roles instead of all (separate by comma, supports wildcards with *)"
 
     class_option :config_file, aliases: "-c", default: "config/deploy.yml", desc: "Path to config file"
     class_option :destination, aliases: "-d", desc: "Specify destination to be used for config file (staging -> deploy.staging.yml)"
@@ -24,6 +24,7 @@ module Mrsk::Cli
 
     def initialize(*)
       super
+      @original_env = ENV.to_h.dup
       load_envs
       initialize_commander(options_with_subcommand_class_options)
     end
@@ -37,12 +38,18 @@ module Mrsk::Cli
         end
       end
 
+      def reload_envs
+        ENV.clear
+        ENV.update(@original_env)
+        load_envs
+      end
+
       def options_with_subcommand_class_options
         options.merge(@_initializer.last[:class_options] || {})
       end
 
       def initialize_commander(options)
-        MRSK.tap do |commander|
+        KAMAL.tap do |commander|
           if options[:verbose]
             ENV["VERBOSE"] = "1" # For backtraces via cli/start
             commander.verbosity = :debug
@@ -66,106 +73,125 @@ module Mrsk::Cli
       def print_runtime
         started_at = Time.now
         yield
-        return Time.now - started_at
+        Time.now - started_at
       ensure
         runtime = Time.now - started_at
         puts "  Finished all in #{sprintf("%.1f seconds", runtime)}"
       end
 
-      def mutating
+      def with_lock
-        return yield if MRSK.holding_lock?
+        if KAMAL.holding_lock?
-
-        MRSK.config.ensure_env_available
-
-        run_hook "pre-connect"
-
-        acquire_lock
-
-        begin
           yield
-        rescue
+        else
-          if MRSK.hold_lock_on_error?
+          ensure_run_and_locks_directory
-            error "  \e[31mDeploy lock was not released\e[0m"
+
-          else
+          acquire_lock
-            release_lock
+
+          begin
+            yield
+          rescue
+            begin
+              release_lock
+            rescue => e
+              say "Error releasing the deploy lock: #{e.message}", :red
+            end
+            raise
           end
 
-          raise
+          release_lock
         end
+      end
 
-        release_lock
+      def confirming(question)
+        return yield if options[:confirmed]
+
+        if ask(question, limited_to: %w[ y N ], default: "N") == "y"
+          yield
+        else
+          say "Aborted", :red
+        end
       end
 
       def acquire_lock
         raise_if_locked do
           say "Acquiring the deploy lock...", :magenta
-          on(MRSK.primary_host) { execute *MRSK.lock.acquire("Automatic deploy lock", MRSK.config.version), verbosity: :debug }
+          on(KAMAL.primary_host) { execute *KAMAL.lock.acquire("Automatic deploy lock", KAMAL.config.version), verbosity: :debug }
         end
 
-        MRSK.holding_lock = true
+        KAMAL.holding_lock = true
       end
 
       def release_lock
         say "Releasing the deploy lock...", :magenta
-        on(MRSK.primary_host) { execute *MRSK.lock.release, verbosity: :debug }
+        on(KAMAL.primary_host) { execute *KAMAL.lock.release, verbosity: :debug }
 
-        MRSK.holding_lock = false
+        KAMAL.holding_lock = false
       end
 
       def raise_if_locked
         yield
       rescue SSHKit::Runner::ExecuteError => e
         if e.message =~ /cannot create directory/
-          on(MRSK.primary_host) { puts capture_with_debug(*MRSK.lock.status) }
+          say "Deploy lock already in place!", :red
-          raise LockError, "Deploy lock found"
+          on(KAMAL.primary_host) { puts capture_with_debug(*KAMAL.lock.status) }
+          raise LockError, "Deploy lock found. Run 'kamal lock help' for more information"
         else
           raise e
         end
       end
 
-      def hold_lock_on_error
-        if MRSK.hold_lock_on_error?
-          yield
-        else
-          MRSK.hold_lock_on_error = true
-          yield
-          MRSK.hold_lock_on_error = false
-        end
-      end
-
       def run_hook(hook, **extra_details)
-        if !options[:skip_hooks] && MRSK.hook.hook_exists?(hook)
+        if !options[:skip_hooks] && KAMAL.hook.hook_exists?(hook)
-          details = { hosts: MRSK.hosts.join(","), command: command, subcommand: subcommand }
+          details = { hosts: KAMAL.hosts.join(","), command: command, subcommand: subcommand }
 
           say "Running the #{hook} hook...", :magenta
           run_locally do
-            MRSK.with_verbosity(:debug) { execute *MRSK.hook.run(hook, **details, **extra_details) }
+            execute *KAMAL.hook.run(hook, **details, **extra_details)
-          rescue SSHKit::Command::Failed
+          rescue SSHKit::Command::Failed => e
-            raise HookError.new("Hook `#{hook}` failed")
+            raise HookError.new("Hook `#{hook}` failed:\n#{e.message}")
           end
         end
       end
 
+      def on(*args, &block)
+        if !KAMAL.connected?
+          run_hook "pre-connect"
+          KAMAL.connected = true
+        end
+
+        super
+      end
+
       def command
-        @mrsk_command ||= begin
+        @kamal_command ||= begin
           invocation_class, invocation_commands = *first_invocation
-          if invocation_class == Mrsk::Cli::Main
+          if invocation_class == Kamal::Cli::Main
             invocation_commands[0]
           else
-            Mrsk::Cli::Main.subcommand_classes.find { |command, clazz| clazz == invocation_class }[0]
+            Kamal::Cli::Main.subcommand_classes.find { |command, clazz| clazz == invocation_class }[0]
           end
         end
       end
 
       def subcommand
-        @mrsk_subcommand ||= begin
+        @kamal_subcommand ||= begin
           invocation_class, invocation_commands = *first_invocation
-          invocation_commands[0] if invocation_class != Mrsk::Cli::Main
+          invocation_commands[0] if invocation_class != Kamal::Cli::Main
         end
       end
 
       def first_invocation
         instance_variable_get("@_invocations").first
       end
-    end
+
+      def ensure_run_and_locks_directory
+        on(KAMAL.hosts) do
+          execute(*KAMAL.server.ensure_run_directory)
+        end
+
+        on(KAMAL.primary_host) do
+          execute(*KAMAL.lock.ensure_locks_directory)
+        end
+      end
+  end
 end

lib/kamal/cli/build.rb

@@ -0,0 +1,148 @@
+require "uri"
+
+class Kamal::Cli::Build < Kamal::Cli::Base
+  class BuildError < StandardError; end
+
+  desc "deliver", "Build app and push app image to registry then pull image on servers"
+  def deliver
+    push
+    pull
+  end
+
+  desc "push", "Build and push app image to registry"
+  def push
+    cli = self
+
+    verify_local_dependencies
+    run_hook "pre-build"
+
+    uncommitted_changes = Kamal::Git.uncommitted_changes
+
+    if KAMAL.config.builder.git_clone?
+      if uncommitted_changes.present?
+        say "Building from a local git clone, so ignoring these uncommitted changes:\n #{uncommitted_changes}", :yellow
+      end
+
+      prepare_clone
+    elsif uncommitted_changes.present?
+      say "Building with uncommitted changes:\n #{uncommitted_changes}", :yellow
+    end
+
+    # Get the command here to ensure the Dir.chdir doesn't interfere with it
+    push = KAMAL.builder.push
+
+    run_locally do
+      begin
+        KAMAL.with_verbosity(:debug) do
+          Dir.chdir(KAMAL.config.builder.build_directory) { execute *push }
+        end
+      rescue SSHKit::Command::Failed => e
+        if e.message =~ /(no builder)|(no such file or directory)/
+          warn "Missing compatible builder, so creating a new one first"
+
+          if cli.create
+            KAMAL.with_verbosity(:debug) do
+              Dir.chdir(KAMAL.config.builder.build_directory) { execute *push }
+            end
+          end
+        else
+          raise
+        end
+      end
+    end
+  end
+
+  desc "pull", "Pull app image from registry onto servers"
+  def pull
+    on(KAMAL.hosts) do
+      execute *KAMAL.auditor.record("Pulled image with version #{KAMAL.config.version}"), verbosity: :debug
+      execute *KAMAL.builder.clean, raise_on_non_zero_exit: false
+      execute *KAMAL.builder.pull
+      execute *KAMAL.builder.validate_image
+    end
+  end
+
+  desc "create", "Create a build setup"
+  def create
+    if (remote_host = KAMAL.config.builder.remote_host)
+      connect_to_remote_host(remote_host)
+    end
+
+    run_locally do
+      begin
+        debug "Using builder: #{KAMAL.builder.name}"
+        execute *KAMAL.builder.create
+      rescue SSHKit::Command::Failed => e
+        if e.message =~ /stderr=(.*)/
+          error "Couldn't create remote builder: #{$1}"
+          false
+        else
+          raise
+        end
+      end
+    end
+  end
+
+  desc "remove", "Remove build setup"
+  def remove
+    run_locally do
+      debug "Using builder: #{KAMAL.builder.name}"
+      execute *KAMAL.builder.remove
+    end
+  end
+
+  desc "details", "Show build setup"
+  def details
+    run_locally do
+      puts "Builder: #{KAMAL.builder.name}"
+      puts capture(*KAMAL.builder.info)
+    end
+  end
+
+  private
+    def verify_local_dependencies
+      run_locally do
+        begin
+          execute *KAMAL.builder.ensure_local_dependencies_installed
+        rescue SSHKit::Command::Failed => e
+          build_error = e.message =~ /command not found/ ?
+            "Docker is not installed locally" :
+            "Docker buildx plugin is not installed locally"
+
+          raise BuildError, build_error
+        end
+      end
+    end
+
+    def connect_to_remote_host(remote_host)
+      remote_uri = URI.parse(remote_host)
+      if remote_uri.scheme == "ssh"
+        host = SSHKit::Host.new(
+          hostname: remote_uri.host,
+          ssh_options: { user: remote_uri.user, port: remote_uri.port }.compact
+        )
+        on(host, options) do
+          execute "true"
+        end
+      end
+    end
+
+    def prepare_clone
+      run_locally do
+        begin
+          info "Cloning repo into build directory `#{KAMAL.config.builder.build_directory}`..."
+
+          execute *KAMAL.builder.create_clone_directory
+          execute *KAMAL.builder.clone
+        rescue SSHKit::Command::Failed => e
+          if e.message =~ /already exists and is not an empty directory/
+            info "Resetting local clone as `#{KAMAL.config.builder.build_directory}` already exists..."
+
+            KAMAL.builder.clone_reset_steps.each { |step| execute *step }
+          else
+            raise
+          end
+        end
+      end
+    end
+end

lib/kamal/cli/env.rb

@@ -0,0 +1,45 @@
+require "tempfile"
+
+class Kamal::Cli::Env < Kamal::Cli::Base
+  desc "push", "Push the env file to the remote hosts"
+  def push
+    with_lock do
+      on(KAMAL.hosts) do
+        execute *KAMAL.auditor.record("Pushed env files"), verbosity: :debug
+
+        KAMAL.roles_on(host).each do |role|
+          execute *KAMAL.app(role: role, host: host).make_env_directory
+          upload! role.env(host).secrets_io, role.env(host).secrets_file, mode: 400
+        end
+      end
+
+      on(KAMAL.accessory_hosts) do
+        KAMAL.accessories_on(host).each do |accessory|
+          accessory_config = KAMAL.config.accessory(accessory)
+          execute *KAMAL.accessory(accessory).make_env_directory
+          upload! accessory_config.env.secrets_io, accessory_config.env.secrets_file, mode: 400
+        end
+      end
+    end
+  end
+
+  desc "delete", "Delete the env file from the remote hosts"
+  def delete
+    with_lock do
+      on(KAMAL.hosts) do
+        execute *KAMAL.auditor.record("Deleted env files"), verbosity: :debug
+
+        KAMAL.roles_on(host).each do |role|
+          execute *KAMAL.app(role: role, host: host).remove_env_file
+        end
+      end
+
+      on(KAMAL.accessory_hosts) do
+        KAMAL.accessories_on(host).each do |accessory|
+          accessory_config = KAMAL.config.accessory(accessory)
+          execute *KAMAL.accessory(accessory).remove_env_file
+        end
+      end
+    end
+  end
+end

lib/kamal/cli/lock.rb

@@ -1,8 +1,11 @@
-class Mrsk::Cli::Lock < Mrsk::Cli::Base
+class Kamal::Cli::Lock < Kamal::Cli::Base
   desc "status", "Report lock status"
   def status
     handle_missing_lock do
-      on(MRSK.primary_host) { puts capture_with_debug(*MRSK.lock.status) }
+      on(KAMAL.primary_host) do
+        execute *KAMAL.server.ensure_run_directory
+        puts capture_with_debug(*KAMAL.lock.status)
+      end
     end
   end
 
@@ -11,7 +14,10 @@ class Mrsk::Cli::Lock < Mrsk::Cli::Base
   def acquire
     message = options[:message]
     raise_if_locked do
-      on(MRSK.primary_host) { execute *MRSK.lock.acquire(message, MRSK.config.version), verbosity: :debug }
+      on(KAMAL.primary_host) do
+        execute *KAMAL.server.ensure_run_directory
+        execute *KAMAL.lock.acquire(message, KAMAL.config.version), verbosity: :debug
+      end
       say "Acquired the deploy lock"
     end
   end
@@ -19,7 +25,10 @@ class Mrsk::Cli::Lock < Mrsk::Cli::Base
   desc "release", "Release the deploy lock"
   def release
     handle_missing_lock do
-      on(MRSK.primary_host) { execute *MRSK.lock.release, verbosity: :debug }
+      on(KAMAL.primary_host) do
+        execute *KAMAL.server.ensure_run_directory
+        execute *KAMAL.lock.release, verbosity: :debug
+      end
       say "Released the deploy lock"
     end
   end

lib/kamal/cli/main.rb

@@ -0,0 +1,261 @@
+class Kamal::Cli::Main < Kamal::Cli::Base
+  desc "setup", "Setup all accessories, push the env, and deploy app to servers"
+  option :skip_push, aliases: "-P", type: :boolean, default: false, desc: "Skip image build and push"
+  def setup
+    print_runtime do
+      with_lock do
+        invoke_options = deploy_options
+
+        say "Ensure Docker is installed...", :magenta
+        invoke "kamal:cli:server:bootstrap", [], invoke_options
+
+        say "Evaluate and push env files...", :magenta
+        invoke "kamal:cli:main:envify", [], invoke_options
+
+        invoke "kamal:cli:accessory:boot", [ "all" ], invoke_options
+        deploy
+      end
+    end
+  end
+
+  desc "deploy", "Deploy app to servers"
+  option :skip_push, aliases: "-P", type: :boolean, default: false, desc: "Skip image build and push"
+  def deploy
+    runtime = print_runtime do
+      invoke_options = deploy_options
+
+      say "Log into image registry...", :magenta
+      invoke "kamal:cli:registry:login", [], invoke_options
+
+      if options[:skip_push]
+        say "Pull app image...", :magenta
+        invoke "kamal:cli:build:pull", [], invoke_options
+      else
+        say "Build and push app image...", :magenta
+        invoke "kamal:cli:build:deliver", [], invoke_options
+      end
+
+      with_lock do
+        run_hook "pre-deploy"
+
+        say "Ensure proxy is running...", :magenta
+        invoke "kamal:cli:proxy:boot", [], invoke_options
+
+        say "Detect stale containers...", :magenta
+        invoke "kamal:cli:app:stale_containers", [], invoke_options.merge(stop: true)
+
+        invoke "kamal:cli:app:boot", [], invoke_options
+
+        say "Prune old containers and images...", :magenta
+        invoke "kamal:cli:prune:all", [], invoke_options
+      end
+    end
+
+    run_hook "post-deploy", runtime: runtime.round
+  end
+
+  desc "redeploy", "Deploy app to servers without bootstrapping servers, starting proxy, pruning, and registry login"
+  option :skip_push, aliases: "-P", type: :boolean, default: false, desc: "Skip image build and push"
+  def redeploy
+    runtime = print_runtime do
+      invoke_options = deploy_options
+
+      if options[:skip_push]
+        say "Pull app image...", :magenta
+        invoke "kamal:cli:build:pull", [], invoke_options
+      else
+        say "Build and push app image...", :magenta
+        invoke "kamal:cli:build:deliver", [], invoke_options
+      end
+
+      with_lock do
+        run_hook "pre-deploy"
+
+        say "Detect stale containers...", :magenta
+        invoke "kamal:cli:app:stale_containers", [], invoke_options.merge(stop: true)
+
+        invoke "kamal:cli:app:boot", [], invoke_options
+      end
+    end
+
+    run_hook "post-deploy", runtime: runtime.round
+  end
+
+  desc "rollback [VERSION]", "Rollback app to VERSION"
+  def rollback(version)
+    rolled_back = false
+    runtime = print_runtime do
+      with_lock do
+        invoke_options = deploy_options
+
+        KAMAL.config.version = version
+        old_version = nil
+
+        if container_available?(version)
+          run_hook "pre-deploy"
+
+          invoke "kamal:cli:app:boot", [], invoke_options.merge(version: version)
+          rolled_back = true
+        else
+          say "The app version '#{version}' is not available as a container (use 'kamal app containers' for available versions)", :red
+        end
+      end
+    end
+
+    run_hook "post-deploy", runtime: runtime.round if rolled_back
+  end
+
+  desc "details", "Show details about all containers"
+  def details
+    invoke "kamal:cli:proxy:details"
+    invoke "kamal:cli:app:details"
+    invoke "kamal:cli:accessory:details", [ "all" ]
+  end
+
+  desc "audit", "Show audit log from servers"
+  def audit
+    on(KAMAL.hosts) do |host|
+      puts_by_host host, capture_with_info(*KAMAL.auditor.reveal)
+    end
+  end
+
+  desc "config", "Show combined config (including secrets!)"
+  def config
+    run_locally do
+      puts Kamal::Utils.redacted(KAMAL.config.to_h).to_yaml
+    end
+  end
+
+  desc "init", "Create config stub in config/deploy.yml and env stub in .env"
+  option :bundle, type: :boolean, default: false, desc: "Add Kamal to the Gemfile and create a bin/kamal binstub"
+  def init
+    require "fileutils"
+
+    if (deploy_file = Pathname.new(File.expand_path("config/deploy.yml"))).exist?
+      puts "Config file already exists in config/deploy.yml (remove first to create a new one)"
+    else
+      FileUtils.mkdir_p deploy_file.dirname
+      FileUtils.cp_r Pathname.new(File.expand_path("templates/deploy.yml", __dir__)), deploy_file
+      puts "Created configuration file in config/deploy.yml"
+    end
+
+    unless (deploy_file = Pathname.new(File.expand_path(".env"))).exist?
+      FileUtils.cp_r Pathname.new(File.expand_path("templates/template.env", __dir__)), deploy_file
+      puts "Created .env file"
+    end
+
+    unless (hooks_dir = Pathname.new(File.expand_path(".kamal/hooks"))).exist?
+      hooks_dir.mkpath
+      Pathname.new(File.expand_path("templates/sample_hooks", __dir__)).each_child do |sample_hook|
+        FileUtils.cp sample_hook, hooks_dir, preserve: true
+      end
+      puts "Created sample hooks in .kamal/hooks"
+    end
+
+    if options[:bundle]
+      if (binstub = Pathname.new(File.expand_path("bin/kamal"))).exist?
+        puts "Binstub already exists in bin/kamal (remove first to create a new one)"
+      else
+        puts "Adding Kamal to Gemfile and bundle..."
+        run_locally do
+          execute :bundle, :add, :kamal
+          execute :bundle, :binstubs, :kamal
+        end
+        puts "Created binstub file in bin/kamal"
+      end
+    end
+  end
+
+  desc "envify", "Create .env by evaluating .env.erb (or .env.staging.erb -> .env.staging when using -d staging)"
+  option :skip_push, aliases: "-P", type: :boolean, default: false, desc: "Skip .env file push"
+  def envify
+    if destination = options[:destination]
+      env_template_path = ".env.#{destination}.erb"
+      env_path          = ".env.#{destination}"
+    else
+      env_template_path = ".env.erb"
+      env_path          = ".env"
+    end
+
+    if Pathname.new(File.expand_path(env_template_path)).exist?
+      File.write(env_path, ERB.new(File.read(env_template_path), trim_mode: "-").result, perm: 0600)
+
+      unless options[:skip_push]
+        reload_envs
+        invoke "kamal:cli:env:push", options
+      end
+    else
+      puts "Skipping envify (no #{env_template_path} exist)"
+    end
+  end
+
+  desc "remove", "Remove proxy, app, accessories, and registry session from servers"
+  option :confirmed, aliases: "-y", type: :boolean, default: false, desc: "Proceed without confirmation question"
+  def remove
+    confirming "This will remove all containers and images. Are you sure?" do
+      with_lock do
+        invoke "kamal:cli:proxy:remove", [], options.without(:confirmed)
+        invoke "kamal:cli:app:remove", [], options.without(:confirmed)
+        invoke "kamal:cli:accessory:remove", [ "all" ], options
+        invoke "kamal:cli:registry:logout", [], options.without(:confirmed)
+      end
+    end
+  end
+
+  desc "version", "Show Kamal version"
+  def version
+    puts Kamal::VERSION
+  end
+
+  desc "accessory", "Manage accessories (db/redis/search)"
+  subcommand "accessory", Kamal::Cli::Accessory
+
+  desc "app", "Manage application"
+  subcommand "app", Kamal::Cli::App
+
+  desc "build", "Build application image"
+  subcommand "build", Kamal::Cli::Build
+
+  desc "env", "Manage environment files"
+  subcommand "env", Kamal::Cli::Env
+
+  desc "lock", "Manage the deploy lock"
+  subcommand "lock", Kamal::Cli::Lock
+
+  desc "prune", "Prune old application images and containers"
+  subcommand "prune", Kamal::Cli::Prune
+
+  desc "registry", "Login and -out of the image registry"
+  subcommand "registry", Kamal::Cli::Registry
+
+  desc "server", "Bootstrap servers with curl and Docker"
+  subcommand "server", Kamal::Cli::Server
+
+  desc "proxy", "Manage load balancer proxy"
+  subcommand "proxy", Kamal::Cli::Proxy
+
+  private
+    def container_available?(version)
+      begin
+        on(KAMAL.hosts) do
+          KAMAL.roles_on(host).each do |role|
+            container_id = capture_with_info(*KAMAL.app(role: role, host: host).container_id_for_version(version))
+            raise "Container not found" unless container_id.present?
+          end
+        end
+      rescue SSHKit::Runner::ExecuteError, SSHKit::Runner::MultipleExecuteError => e
+        if e.message =~ /Container not found/
+          say "Error looking for container version #{version}: #{e.message}"
+          return false
+        else
+          raise
+        end
+      end
+
+      true
+    end
+
+    def deploy_options
+      { "version" => KAMAL.config.version }.merge(options.without("skip_push"))
+    end
+end

lib/kamal/cli/proxy.rb

@@ -0,0 +1,120 @@
+class Kamal::Cli::Proxy < Kamal::Cli::Base
+  desc "boot", "Boot proxy on servers"
+  def boot
+    with_lock do
+      on(KAMAL.proxy_hosts) do
+        execute *KAMAL.registry.login
+        execute *KAMAL.proxy.start_or_run
+      end
+    end
+  end
+
+  desc "reboot", "Reboot proxy on servers (stop container, remove container, start new container)"
+  option :rolling, type: :boolean, default: false, desc: "Reboot proxy on hosts in sequence, rather than in parallel"
+  option :confirmed, aliases: "-y", type: :boolean, default: false, desc: "Proceed without confirmation question"
+  def reboot
+    confirming "This will cause a brief outage on each host. Are you sure?" do
+      with_lock do
+        host_groups = options[:rolling] ? KAMAL.proxy_hosts : [ KAMAL.proxy_hosts ]
+        host_groups.each do |hosts|
+          host_list = Array(hosts).join(",")
+          run_hook "pre-proxy-reboot", hosts: host_list
+          on(hosts) do
+            execute *KAMAL.auditor.record("Rebooted proxy"), verbosity: :debug
+            execute *KAMAL.registry.login
+            execute *KAMAL.proxy.stop, raise_on_non_zero_exit: false
+            execute *KAMAL.proxy.remove_container
+            execute *KAMAL.proxy.run
+          end
+          run_hook "post-proxy-reboot", hosts: host_list
+        end
+      end
+    end
+  end
+
+  desc "start", "Start existing proxy container on servers"
+  def start
+    with_lock do
+      on(KAMAL.proxy_hosts) do
+        execute *KAMAL.auditor.record("Started proxy"), verbosity: :debug
+        execute *KAMAL.proxy.start
+      end
+    end
+  end
+
+  desc "stop", "Stop existing proxy container on servers"
+  def stop
+    with_lock do
+      on(KAMAL.proxy_hosts) do
+        execute *KAMAL.auditor.record("Stopped proxy"), verbosity: :debug
+        execute *KAMAL.proxy.stop, raise_on_non_zero_exit: false
+      end
+    end
+  end
+
+  desc "restart", "Restart existing proxy container on servers"
+  def restart
+    with_lock do
+      stop
+      start
+    end
+  end
+
+  desc "details", "Show details about proxy container from servers"
+  def details
+    on(KAMAL.proxy_hosts) { |host| puts_by_host host, capture_with_info(*KAMAL.proxy.info), type: "Proxy" }
+  end
+
+  desc "logs", "Show log lines from proxy on servers"
+  option :since, aliases: "-s", desc: "Show logs since timestamp (e.g. 2013-01-02T13:23:37Z) or relative (e.g. 42m for 42 minutes)"
+  option :lines, type: :numeric, aliases: "-n", desc: "Number of log lines to pull from each server"
+  option :grep, aliases: "-g", desc: "Show lines with grep match only (use this to fetch specific requests by id)"
+  option :follow, aliases: "-f", desc: "Follow logs on primary server (or specific host set by --hosts)"
+  def logs
+    grep = options[:grep]
+
+    if options[:follow]
+      run_locally do
+        info "Following logs on #{KAMAL.primary_host}..."
+        info KAMAL.proxy.follow_logs(host: KAMAL.primary_host, grep: grep)
+        exec KAMAL.proxy.follow_logs(host: KAMAL.primary_host, grep: grep)
+      end
+    else
+      since = options[:since]
+      lines = options[:lines].presence || ((since || grep) ? nil : 100) # Default to 100 lines if since or grep isn't set
+
+      on(KAMAL.proxy_hosts) do |host|
+        puts_by_host host, capture(*KAMAL.proxy.logs(since: since, lines: lines, grep: grep)), type: "Proxy"
+      end
+    end
+  end
+
+  desc "remove", "Remove proxy container and image from servers"
+  def remove
+    with_lock do
+      stop
+      remove_container
+      remove_image
+    end
+  end
+
+  desc "remove_container", "Remove proxy container from servers", hide: true
+  def remove_container
+    with_lock do
+      on(KAMAL.proxy_hosts) do
+        execute *KAMAL.auditor.record("Removed proxy container"), verbosity: :debug
+        execute *KAMAL.proxy.remove_container
+      end
+    end
+  end
+
+  desc "remove_image", "Remove proxy image from servers", hide: true
+  def remove_image
+    with_lock do
+      on(KAMAL.proxy_hosts) do
+        execute *KAMAL.auditor.record("Removed proxy image"), verbosity: :debug
+        execute *KAMAL.proxy.remove_image
+      end
+    end
+  end
+end

lib/kamal/cli/prune.rb

@@ -0,0 +1,34 @@
+class Kamal::Cli::Prune < Kamal::Cli::Base
+  desc "all", "Prune unused images and stopped containers"
+  def all
+    with_lock do
+      containers
+      images
+    end
+  end
+
+  desc "images", "Prune unused images"
+  def images
+    with_lock do
+      on(KAMAL.hosts) do
+        execute *KAMAL.auditor.record("Pruned images"), verbosity: :debug
+        execute *KAMAL.prune.dangling_images
+        execute *KAMAL.prune.tagged_images
+      end
+    end
+  end
+
+  desc "containers", "Prune all stopped containers, except the last n (default 5)"
+  option :retain, type: :numeric, default: nil, desc: "Number of containers to retain"
+  def containers
+    retain = options.fetch(:retain, KAMAL.config.retain_containers)
+    raise "retain must be at least 1" if retain < 1
+
+    with_lock do
+      on(KAMAL.hosts) do
+        execute *KAMAL.auditor.record("Pruned containers"), verbosity: :debug
+        execute *KAMAL.prune.app_containers(retain: retain)
+      end
+    end
+  end
+end

lib/kamal/cli/registry.rb

@@ -1,8 +1,8 @@
-class Mrsk::Cli::Registry < Mrsk::Cli::Base
+class Kamal::Cli::Registry < Kamal::Cli::Base
   desc "login", "Log in to registry locally and remotely"
   def login
-    run_locally    { execute *MRSK.registry.login }
+    run_locally    { execute *KAMAL.registry.login }
-    on(MRSK.hosts) { execute *MRSK.registry.login }
+    on(KAMAL.hosts) { execute *KAMAL.registry.login }
   # FIXME: This rescue needed?
   rescue ArgumentError => e
     puts e.message
@@ -10,7 +10,7 @@ class Mrsk::Cli::Registry < Mrsk::Cli::Base
 
   desc "logout", "Log out of registry remotely"
   def logout
-    on(MRSK.hosts) { execute *MRSK.registry.logout }
+    on(KAMAL.hosts) { execute *KAMAL.registry.logout }
   # FIXME: This rescue needed?
   rescue ArgumentError => e
     puts e.message

lib/kamal/cli/server.rb

@@ -0,0 +1,49 @@
+class Kamal::Cli::Server < Kamal::Cli::Base
+  desc "exec", "Run a custom command on the server (use --help to show options)"
+  option :interactive, type: :boolean, aliases: "-i", default: false, desc: "Run the command interactively (use for console/bash)"
+  def exec(cmd)
+    hosts = KAMAL.hosts | KAMAL.accessory_hosts
+
+    case
+    when options[:interactive]
+      host = KAMAL.primary_host
+
+      say "Running '#{cmd}' on #{host} interactively...", :magenta
+
+      run_locally { exec KAMAL.server.run_over_ssh(cmd, host: host) }
+    else
+      say "Running '#{cmd}' on #{hosts.join(', ')}...", :magenta
+
+      on(hosts) do |host|
+        execute *KAMAL.auditor.record("Executed cmd '#{cmd}' on #{host}"), verbosity: :debug
+        puts_by_host host, capture_with_info(cmd)
+      end
+    end
+  end
+
+  desc "bootstrap", "Set up Docker to run Kamal apps"
+  def bootstrap
+    with_lock do
+      missing = []
+
+      on(KAMAL.hosts | KAMAL.accessory_hosts) do |host|
+        unless execute(*KAMAL.docker.installed?, raise_on_non_zero_exit: false)
+          if execute(*KAMAL.docker.superuser?, raise_on_non_zero_exit: false)
+            info "Missing Docker on #{host}. Installing…"
+            execute *KAMAL.docker.install
+          else
+            missing << host
+          end
+        end
+
+        execute(*KAMAL.server.ensure_run_directory)
+      end
+
+      if missing.any?
+        raise "Docker is not installed on #{missing.join(", ")} and can't be automatically installed without having root access and either `wget` or `curl`. Install Docker manually: https://docs.docker.com/engine/install/"
+      end
+
+      run_hook "docker-setup"
+    end
+  end
+end

lib/kamal/cli/templates/deploy.yml

@@ -16,9 +16,10 @@ registry:
 
   # Always use an access token rather than real password when possible.
   password:
-    - MRSK_REGISTRY_PASSWORD
+    - KAMAL_REGISTRY_PASSWORD
 
 # Inject ENV variables into containers (secrets come from .env).
+# Remember to run `kamal env push` after making changes!
 # env:
 #   clear:
 #     DB_HOST: 192.168.0.2
@@ -52,7 +53,7 @@ registry:
 #         - MYSQL_ROOT_PASSWORD
 #     files:
 #       - config/mysql/production.cnf:/etc/mysql/my.cnf
-#       - db/production.sql.erb:/docker-entrypoint-initdb.d/setup.sql
+#       - db/production.sql:/docker-entrypoint-initdb.d/setup.sql
 #     directories:
 #       - data:/var/lib/mysql
 #   redis:
@@ -62,13 +63,28 @@ registry:
 #     directories:
 #       - data:/data
 
-# Configure custom arguments for Traefik
+# Bridge fingerprinted assets, like JS and CSS, between versions to avoid
-# traefik:
+# hitting 404 on in-flight requests. Combines all files from new and old
-#   args:
+# version inside the asset_path.
-#     accesslog: true
+#
-#     accesslog.format: json
+# If your app is using the Sprockets gem, ensure it sets `config.assets.manifest`.
+# See https://github.com/basecamp/kamal/issues/626 for details
+#
+# asset_path: /rails/public/assets
 
-# Configure a custom healthcheck (default is /up on port 3000)
+# Configure rolling deploys by setting a wait time between batches of restarts.
-# healthcheck:
+# boot:
-#   path: /healthz
+#   limit: 10 # Can also specify as a percentage of total hosts, such as "25%"
-#   port: 4000
+#   wait: 2
+
+# Configure the role used to determine the primary_host. This host takes
+# deploy locks, runs health checks during the deploy, and follow logs, etc.
+#
+# Caution: there's no support for role renaming yet, so be careful to cleanup
+#          the previous role on the deployed hosts.
+# primary_role: web
+
+# Controls if we abort when see a role with no hosts. Disabling this may be
+# useful for more complex deploy configurations.
+#
+# allow_empty_roles: false

lib/kamal/cli/templates/sample_hooks/docker-setup.sample

@@ -0,0 +1,7 @@
+#!/usr/bin/env ruby
+
+# A sample docker-setup hook
+#
+# Sets up a Docker network which can then be used by the application’s containers
+
+ssh user@example.com docker network create kamal

lib/kamal/cli/templates/sample_hooks/post-deploy.sample

@@ -0,0 +1,14 @@
+#!/bin/sh
+
+# A sample post-deploy hook
+#
+# These environment variables are available:
+# KAMAL_RECORDED_AT
+# KAMAL_PERFORMER
+# KAMAL_VERSION
+# KAMAL_HOSTS
+# KAMAL_ROLE (if set)
+# KAMAL_DESTINATION (if set)
+# KAMAL_RUNTIME
+
+echo "$KAMAL_PERFORMER deployed $KAMAL_VERSION to $KAMAL_DESTINATION in $KAMAL_RUNTIME seconds"

lib/kamal/cli/templates/sample_hooks/post-proxy-reboot.sample

@@ -0,0 +1,3 @@
+#!/bin/sh
+
+echo "Rebooted proxy on $KAMAL_HOSTS"

lib/kamal/cli/templates/sample_hooks/pre-build.sample

@@ -9,12 +9,12 @@
 # 4. The version we are deploying matches the remote
 #
 # These environment variables are available:
-# MRSK_RECORDED_AT
+# KAMAL_RECORDED_AT
-# MRSK_PERFORMER
+# KAMAL_PERFORMER
-# MRSK_VERSION
+# KAMAL_VERSION
-# MRSK_HOSTS
+# KAMAL_HOSTS
-# MRSK_ROLE (if set)
+# KAMAL_ROLE (if set)
-# MRSK_DESTINATION (if set)
+# KAMAL_DESTINATION (if set)
 
 if [ -n "$(git status --porcelain)" ]; then
   echo "Git checkout is not clean, aborting..." >&2
@@ -32,7 +32,7 @@ fi
 current_branch=$(git branch --show-current)
 
 if [ -z "$current_branch" ]; then
-  echo "No git remote set, aborting..." >&2
+  echo "Not on a git branch, aborting..." >&2
   exit 1
 fi
 
@@ -43,8 +43,8 @@ if [ -z "$remote_head" ]; then
   exit 1
 fi
 
-if [ "$MRSK_VERSION" != "$remote_head" ]; then
+if [ "$KAMAL_VERSION" != "$remote_head" ]; then
-  echo "Version ($MRSK_VERSION) does not match remote HEAD ($remote_head), aborting..." >&2
+  echo "Version ($KAMAL_VERSION) does not match remote HEAD ($remote_head), aborting..." >&2
   exit 1
 fi
 

lib/kamal/cli/templates/sample_hooks/pre-connect.sample

@@ -5,15 +5,15 @@
 # Warms DNS before connecting to hosts in parallel
 #
 # These environment variables are available:
-# MRSK_RECORDED_AT
+# KAMAL_RECORDED_AT
-# MRSK_PERFORMER
+# KAMAL_PERFORMER
-# MRSK_VERSION
+# KAMAL_VERSION
-# MRSK_HOSTS
+# KAMAL_HOSTS
-# MRSK_ROLE (if set)
+# KAMAL_ROLE (if set)
-# MRSK_DESTINATION (if set)
+# KAMAL_DESTINATION (if set)
-# MRSK_RUNTIME
+# KAMAL_RUNTIME
 
-hosts = ENV["MRSK_HOSTS"].split(",")
+hosts = ENV["KAMAL_HOSTS"].split(",")
 results = nil
 max = 3
 

lib/kamal/cli/templates/sample_hooks/pre-deploy.sample

@@ -7,17 +7,17 @@
 # Fails unless the combined status is "success"
 #
 # These environment variables are available:
-# MRSK_RECORDED_AT
+# KAMAL_RECORDED_AT
-# MRSK_PERFORMER
+# KAMAL_PERFORMER
-# MRSK_VERSION
+# KAMAL_VERSION
-# MRSK_HOSTS
+# KAMAL_HOSTS
-# MRSK_COMMAND
+# KAMAL_COMMAND
-# MRSK_SUBCOMMAND
+# KAMAL_SUBCOMMAND
-# MRSK_ROLE (if set)
+# KAMAL_ROLE (if set)
-# MRSK_DESTINATION (if set)
+# KAMAL_DESTINATION (if set)
 
 # Only check the build status for production deployments
-if ENV["MRSK_COMMAND"] == "rollback" || ENV["MRSK_DESTINATION"] != "production"
+if ENV["KAMAL_COMMAND"] == "rollback" || ENV["KAMAL_DESTINATION"] != "production"
   exit 0
 end
 

lib/kamal/cli/templates/sample_hooks/pre-proxy-reboot.sample

@@ -0,0 +1,3 @@
+#!/bin/sh
+
+echo "Rebooting proxy on $KAMAL_HOSTS..."

lib/kamal/cli/templates/template.env

@@ -0,0 +1,2 @@
+KAMAL_REGISTRY_PASSWORD=change-this
+RAILS_MASTER_KEY=another-env

lib/kamal/commander.rb

@@ -0,0 +1,156 @@
+require "active_support/core_ext/enumerable"
+require "active_support/core_ext/module/delegation"
+
+class Kamal::Commander
+  attr_accessor :verbosity, :holding_lock, :connected
+  delegate :hosts, :roles, :primary_host, :primary_role, :roles_on, :proxy_hosts, :accessory_hosts, to: :specifics
+
+  def initialize
+    self.verbosity = :info
+    self.holding_lock = false
+    self.connected = false
+    @specifics = nil
+  end
+
+  def config
+    @config ||= Kamal::Configuration.create_from(**@config_kwargs).tap do |config|
+      @config_kwargs = nil
+      configure_sshkit_with(config)
+    end
+  end
+
+  def configure(**kwargs)
+    @config, @config_kwargs = nil, kwargs
+  end
+
+  attr_reader :specific_roles, :specific_hosts
+
+  def specific_primary!
+    @specifics = nil
+    self.specific_hosts = [ config.primary_host ]
+  end
+
+  def specific_roles=(role_names)
+    @specifics = nil
+    if role_names.present?
+      @specific_roles = Kamal::Utils.filter_specific_items(role_names, config.roles)
+
+      if @specific_roles.empty?
+        raise ArgumentError, "No --roles match for #{role_names.join(',')}"
+      end
+
+      @specific_roles
+    end
+  end
+
+  def specific_hosts=(hosts)
+    @specifics = nil
+    if hosts.present?
+      @specific_hosts = Kamal::Utils.filter_specific_items(hosts, config.all_hosts)
+
+      if @specific_hosts.empty?
+        raise ArgumentError, "No --hosts match for #{hosts.join(',')}"
+      end
+
+      @specific_hosts
+    end
+  end
+
+  def accessory_names
+    config.accessories&.collect(&:name) || []
+  end
+
+  def accessories_on(host)
+    config.accessories.select { |accessory| accessory.hosts.include?(host.to_s) }.map(&:name)
+  end
+
+
+  def app(role: nil, host: nil)
+    Kamal::Commands::App.new(config, role: role, host: host)
+  end
+
+  def accessory(name)
+    Kamal::Commands::Accessory.new(config, name: name)
+  end
+
+  def auditor(**details)
+    Kamal::Commands::Auditor.new(config, **details)
+  end
+
+  def builder
+    @builder ||= Kamal::Commands::Builder.new(config)
+  end
+
+  def docker
+    @docker ||= Kamal::Commands::Docker.new(config)
+  end
+
+  def hook
+    @hook ||= Kamal::Commands::Hook.new(config)
+  end
+
+  def lock
+    @lock ||= Kamal::Commands::Lock.new(config)
+  end
+
+  def prune
+    @prune ||= Kamal::Commands::Prune.new(config)
+  end
+
+  def registry
+    @registry ||= Kamal::Commands::Registry.new(config)
+  end
+
+  def server
+    @server ||= Kamal::Commands::Server.new(config)
+  end
+
+  def proxy
+    @proxy ||= Kamal::Commands::Proxy.new(config)
+  end
+
+
+  def with_verbosity(level)
+    old_level = self.verbosity
+
+    self.verbosity = level
+    SSHKit.config.output_verbosity = level
+
+    yield
+  ensure
+    self.verbosity = old_level
+    SSHKit.config.output_verbosity = old_level
+  end
+
+  def boot_strategy
+    if config.boot.limit.present?
+      { in: :groups, limit: config.boot.limit, wait: config.boot.wait }
+    else
+      {}
+    end
+  end
+
+  def holding_lock?
+    self.holding_lock
+  end
+
+  def connected?
+    self.connected
+  end
+
+  private
+    # Lazy setup of SSHKit
+    def configure_sshkit_with(config)
+      SSHKit::Backend::Netssh.pool.idle_timeout = config.sshkit.pool_idle_timeout
+      SSHKit::Backend::Netssh.configure do |sshkit|
+        sshkit.max_concurrent_starts = config.sshkit.max_concurrent_starts
+        sshkit.ssh_options = config.ssh.options
+      end
+      SSHKit.config.command_map[:docker] = "docker" # No need to use /usr/bin/env, just clogs up the logs
+      SSHKit.config.output_verbosity = verbosity
+    end
+
+    def specifics
+      @specifics ||= Kamal::Commander::Specifics.new(config, specific_hosts, specific_roles)
+    end
+end

lib/kamal/commander/specifics.rb

@@ -0,0 +1,49 @@
+class Kamal::Commander::Specifics
+  attr_reader :primary_host, :primary_role, :hosts, :roles
+  delegate :stable_sort!, to: Kamal::Utils
+
+  def initialize(config, specific_hosts, specific_roles)
+    @config, @specific_hosts, @specific_roles = config, specific_hosts, specific_roles
+
+    @roles, @hosts = specified_roles, specified_hosts
+
+    @primary_host = specific_hosts&.first || primary_specific_role&.primary_host || config.primary_host
+    @primary_role = primary_or_first_role(roles_on(primary_host))
+
+    stable_sort!(roles) { |role| role == primary_role ? 0 : 1 }
+    stable_sort!(hosts) { |host| roles_on(host).any? { |role| role == primary_role } ? 0 : 1 }
+  end
+
+  def roles_on(host)
+    roles.select { |role| role.hosts.include?(host.to_s) }
+  end
+
+  def proxy_hosts
+    config.proxy_hosts & specified_hosts
+  end
+
+  def accessory_hosts
+    specific_hosts || config.accessories.flat_map(&:hosts)
+  end
+
+  private
+    attr_reader :config, :specific_hosts, :specific_roles
+
+    def primary_specific_role
+      primary_or_first_role(specific_roles) if specific_roles.present?
+    end
+
+    def primary_or_first_role(roles)
+      roles.detect { |role| role == config.primary_role } || roles.first
+    end
+
+    def specified_roles
+      (specific_roles || config.roles) \
+        .select { |role| ((specific_hosts || config.all_hosts) & role.hosts).any? }
+    end
+
+    def specified_hosts
+      (specific_hosts || config.all_hosts) \
+        .select { |host| (specific_roles || config.roles).flat_map(&:hosts).include?(host) }
+    end
+end

lib/kamal/commands.rb

@@ -0,0 +1,2 @@
+module Kamal::Commands
+end

lib/kamal/commands/accessory.rb

@@ -1,4 +1,4 @@
-class Mrsk::Commands::Accessory < Mrsk::Commands::Base
+class Kamal::Commands::Accessory < Kamal::Commands::Base
   attr_reader :accessory_config
   delegate :service_name, :image, :hosts, :port, :files, :directories, :cmd,
            :publish_args, :env_args, :volume_args, :label_args, :option_args, to: :accessory_config
@@ -86,14 +86,6 @@ class Mrsk::Commands::Accessory < Mrsk::Commands::Base
     end
   end
 
-  def make_directory_for(remote_file)
-    make_directory Pathname.new(remote_file).dirname.to_s
-  end
-
-  def make_directory(path)
-    [ :mkdir, "-p", path ]
-  end
-
   def remove_service_directory
     [ :rm, "-rf", service_name ]
   end
@@ -106,6 +98,14 @@ class Mrsk::Commands::Accessory < Mrsk::Commands::Base
     docker :image, :rm, "--force", image
   end
 
+  def make_env_directory
+    make_directory accessory_config.env.secrets_directory
+  end
+
+  def remove_env_file
+    [ :rm, "-f", accessory_config.env.secrets_file ]
+  end
+
   private
     def service_filter
       [ "--filter", "label=service=#{service_name}" ]

lib/kamal/commands/app.rb

@@ -0,0 +1,126 @@
+class Kamal::Commands::App < Kamal::Commands::Base
+  include Assets, Containers, Execution, Images, Logging
+
+  ACTIVE_DOCKER_STATUSES = [ :running, :restarting ]
+
+  attr_reader :role, :host
+
+  def initialize(config, role: nil, host: nil)
+    super(config)
+    @role = role
+    @host = host
+  end
+
+  def run(hostname: nil)
+    docker :run,
+      "--detach",
+      "--restart unless-stopped",
+      "--name", container_name,
+      *([ "--hostname", hostname ] if hostname),
+      "-e", "KAMAL_CONTAINER_NAME=\"#{container_name}\"",
+      "-e", "KAMAL_VERSION=\"#{config.version}\"",
+      *role.env_args(host),
+      *role.logging_args,
+      *config.volume_args,
+      *role.asset_volume_args,
+      *role.label_args,
+      *role.option_args,
+      config.absolute_image,
+      role.cmd
+  end
+
+  def start
+    docker :start, container_name
+  end
+
+  def status(version:)
+    pipe container_id_for_version(version), xargs(docker(:inspect, "--format", DOCKER_HEALTH_STATUS_FORMAT))
+  end
+
+  def stop(version: nil)
+    pipe \
+      version ? container_id_for_version(version) : current_running_container_id,
+      xargs(config.stop_wait_time ? docker(:stop, "-t", config.stop_wait_time) : docker(:stop))
+  end
+
+  def info
+    docker :ps, *filter_args
+  end
+
+
+  def current_running_container_id
+    current_running_container(format: "--quiet")
+  end
+
+  def container_id_for_version(version, only_running: false)
+    container_id_for(container_name: container_name(version), only_running: only_running)
+  end
+
+  def container_name(version = nil)
+    [ role.container_prefix, version || config.version ].compact.join("-")
+  end
+
+  def current_running_version
+    pipe \
+      current_running_container(format: "--format '{{.Names}}'"),
+      extract_version_from_name
+  end
+
+  def list_versions(*docker_args, statuses: nil)
+    pipe \
+      docker(:ps, *filter_args(statuses: statuses), *docker_args, "--format", '"{{.Names}}"'),
+      extract_version_from_name
+  end
+
+
+  def make_env_directory
+    make_directory role.env(host).secrets_directory
+  end
+
+  def remove_env_file
+    [ :rm, "-f", role.env(host).secrets_file ]
+  end
+
+
+  private
+    def container_name(version = nil)
+      [ role.container_prefix, version || config.version ].compact.join("-")
+    end
+
+    def latest_image_id
+      docker :image, :ls, *argumentize("--filter", "reference=#{config.latest_image}"), "--format", "'{{.ID}}'"
+    end
+
+    def current_running_container(format:)
+      pipe \
+        shell(chain(latest_image_container(format: format), latest_container(format: format))),
+        [ :head, "-1" ]
+    end
+
+    def latest_image_container(format:)
+      latest_container format: format, filters: [ "ancestor=$(#{latest_image_id.join(" ")})" ]
+    end
+
+    def latest_container(format:, filters: nil)
+      docker :ps, "--latest", *format, *filter_args(statuses: ACTIVE_DOCKER_STATUSES), argumentize("--filter", filters)
+    end
+
+    def filter_args(statuses: nil)
+      argumentize "--filter", filters(statuses: statuses)
+    end
+
+    def extract_version_from_name
+      # Extract SHA from "service-role-dest-SHA"
+      %(while read line; do echo ${line##{role.container_prefix}-}; done)
+    end
+
+    def filters(statuses: nil)
+      [ "label=service=#{config.service}" ].tap do |filters|
+        filters << "label=destination=#{config.destination}" if config.destination
+        filters << "label=role=#{role}" if role
+        statuses&.each do |status|
+          filters << "status=#{status}"
+        end
+      end
+    end
+end

lib/kamal/commands/app/assets.rb

@@ -0,0 +1,51 @@
+module Kamal::Commands::App::Assets
+  def extract_assets
+    asset_container = "#{role.container_prefix}-assets"
+
+    combine \
+      make_directory(role.asset_extracted_path),
+      [ *docker(:stop, "-t 1", asset_container, "2> /dev/null"), "|| true" ],
+      docker(:run, "--name", asset_container, "--detach", "--rm", config.absolute_image, "sleep 1000000"),
+      docker(:cp, "-L", "#{asset_container}:#{role.asset_path}/.", role.asset_extracted_path),
+      docker(:stop, "-t 1", asset_container),
+      by: "&&"
+  end
+
+  def sync_asset_volumes(old_version: nil)
+    new_extracted_path, new_volume_path = role.asset_extracted_path(config.version), role.asset_volume.host_path
+    if old_version.present?
+      old_extracted_path, old_volume_path = role.asset_extracted_path(old_version), role.asset_volume(old_version).host_path
+    end
+
+    commands = [ make_directory(new_volume_path), copy_contents(new_extracted_path, new_volume_path) ]
+
+    if old_version.present?
+      commands << copy_contents(new_extracted_path, old_volume_path, continue_on_error: true)
+      commands << copy_contents(old_extracted_path, new_volume_path, continue_on_error: true)
+    end
+
+    chain *commands
+  end
+
+  def clean_up_assets
+    chain \
+      find_and_remove_older_siblings(role.asset_extracted_path),
+      find_and_remove_older_siblings(role.asset_volume_path)
+  end
+
+  private
+    def find_and_remove_older_siblings(path)
+      [
+        :find,
+        Pathname.new(path).dirname.to_s,
+        "-maxdepth 1",
+        "-name", "'#{role.container_prefix}-*'",
+        "!", "-name", Pathname.new(path).basename.to_s,
+        "-exec rm -rf \"{}\" +"
+      ]
+    end
+
+    def copy_contents(source, destination, continue_on_error: false)
+      [ :cp, "-rnT", "#{source}", destination, *("|| true" if continue_on_error) ]
+    end
+end

lib/kamal/commands/app/containers.rb

@@ -0,0 +1,32 @@
+module Kamal::Commands::App::Containers
+  DOCKER_HEALTH_LOG_FORMAT    = "'{{json .State.Health}}'"
+
+  def list_containers
+    docker :container, :ls, "--all", *filter_args
+  end
+
+  def list_container_names
+    [ *list_containers, "--format", "'{{ .Names }}'" ]
+  end
+
+  def remove_container(version:)
+    pipe \
+      container_id_for(container_name: container_name(version)),
+      xargs(docker(:container, :rm))
+  end
+
+  def rename_container(version:, new_version:)
+    docker :rename, container_name(version), container_name(new_version)
+  end
+
+  def remove_containers
+    docker :container, :prune, "--force", *filter_args
+  end
+
+  def container_endpoint(version:)
+    pipe \
+      container_id_for(container_name: container_name(version)),
+      xargs(docker(:inspect, "--format", "'{{.NetworkSettings.IPAddress}}{{range $k, $v := .NetworkSettings.Ports}}{{printf \":%s\" $k}}{{break}}{{end}}'")),
+      [ :sed, "-e", "'s/\\/tcp$//'" ]
+  end
+end

lib/kamal/commands/app/execution.rb

@@ -0,0 +1,29 @@
+module Kamal::Commands::App::Execution
+  def execute_in_existing_container(*command, interactive: false, env:)
+    docker :exec,
+      ("-it" if interactive),
+      *argumentize("--env", env),
+      container_name,
+      *command
+  end
+
+  def execute_in_new_container(*command, interactive: false, env:)
+    docker :run,
+      ("-it" if interactive),
+      "--rm",
+      *role&.env_args(host),
+      *argumentize("--env", env),
+      *config.volume_args,
+      *role&.option_args,
+      config.absolute_image,
+      *command
+  end
+
+  def execute_in_existing_container_over_ssh(*command,  env:)
+    run_over_ssh execute_in_existing_container(*command, interactive: true, env: env), host: host
+  end
+
+  def execute_in_new_container_over_ssh(*command, env:)
+    run_over_ssh execute_in_new_container(*command, interactive: true, env: env), host: host
+  end
+end

lib/kamal/commands/app/images.rb

@@ -0,0 +1,13 @@
+module Kamal::Commands::App::Images
+  def list_images
+    docker :image, :ls, config.repository
+  end
+
+  def remove_images
+    docker :image, :prune, "--all", "--force", *filter_args
+  end
+
+  def tag_latest_image
+    docker :tag, config.absolute_image, config.latest_image
+  end
+end

lib/kamal/commands/app/logging.rb

@@ -0,0 +1,18 @@
+module Kamal::Commands::App::Logging
+  def logs(version: nil, since: nil, lines: nil, grep: nil)
+    pipe \
+      version ? container_id_for_version(version) : current_running_container_id,
+      "xargs docker logs#{" --since #{since}" if since}#{" --tail #{lines}" if lines} 2>&1",
+      ("grep '#{grep}'" if grep)
+  end
+
+  def follow_logs(host:, lines: nil, grep: nil)
+    run_over_ssh \
+      pipe(
+        current_running_container_id,
+        "xargs docker logs --timestamps#{" --tail #{lines}" if lines} --follow 2>&1",
+        (%(grep "#{grep}") if grep)
+      ),
+      host: host
+  end
+end

lib/kamal/commands/auditor.rb

@@ -1,4 +1,4 @@
-class Mrsk::Commands::Auditor < Mrsk::Commands::Base
+class Kamal::Commands::Auditor < Kamal::Commands::Base
   attr_reader :details
 
   def initialize(config, **details)
@@ -19,7 +19,9 @@ class Mrsk::Commands::Auditor < Mrsk::Commands::Base
 
   private
     def audit_log_file
-      [ "mrsk", config.service, config.destination, "audit.log" ].compact.join("-")
+      file = [ config.service, config.destination, "audit.log" ].compact.join("-")
+
+      File.join(config.run_directory, file)
     end
 
     def audit_tags(**details)

lib/kamal/commands/base.rb

@@ -1,9 +1,8 @@
-module Mrsk::Commands
+module Kamal::Commands
   class Base
-    delegate :sensitive, :argumentize, to: Mrsk::Utils
+    delegate :sensitive, :argumentize, to: Kamal::Utils
 
     DOCKER_HEALTH_STATUS_FORMAT = "'{{if .State.Health}}{{.State.Health.Status}}{{else}}{{.State.Status}}{{end}}'"
-    DOCKER_HEALTH_LOG_FORMAT    = "'{{json .State.Health}}'"
 
     attr_accessor :config
 
@@ -13,12 +12,12 @@ module Mrsk::Commands
 
     def run_over_ssh(*command, host:)
       "ssh".tap do |cmd|
-        if config.ssh_proxy && config.ssh_proxy.is_a?(Net::SSH::Proxy::Jump)
+        if config.ssh.proxy && config.ssh.proxy.is_a?(Net::SSH::Proxy::Jump)
-          cmd << " -J #{config.ssh_proxy.jump_proxies}"
+          cmd << " -J #{config.ssh.proxy.jump_proxies}"
-        elsif config.ssh_proxy && config.ssh_proxy.is_a?(Net::SSH::Proxy::Command)
+        elsif config.ssh.proxy && config.ssh.proxy.is_a?(Net::SSH::Proxy::Command)
-          cmd << " -o ProxyCommand='#{config.ssh_proxy.command_line_template}'"
+          cmd << " -o ProxyCommand='#{config.ssh.proxy.command_line_template}'"
         end
-        cmd << " -t #{config.ssh_user}@#{host} '#{command.join(" ")}'"
+        cmd << " -t #{config.ssh.user}@#{host} -p #{config.ssh.port} '#{command.join(" ").gsub("'", "'\\\\''")}'"
       end
     end
 
@@ -26,6 +25,18 @@ module Mrsk::Commands
       docker :container, :ls, *("--all" unless only_running), "--filter", "name=^#{container_name}$", "--quiet"
     end
 
+    def make_directory_for(remote_file)
+      make_directory Pathname.new(remote_file).dirname.to_s
+    end
+
+    def make_directory(path)
+      [ :mkdir, "-p", path ]
+    end
+
+    def remove_directory(path)
+      [ :rm, "-r", path ]
+    end
+
     private
       def combine(*commands, by: "&&")
         commands
@@ -50,16 +61,28 @@ module Mrsk::Commands
         combine *commands, by: ">"
       end
 
+      def any(*commands)
+        combine *commands, by: "||"
+      end
+
       def xargs(command)
         [ :xargs, command ].flatten
       end
 
+      def shell(command)
+        [ :sh, "-c", "'#{command.flatten.join(" ").gsub("'", "'\\\\''")}'" ]
+      end
+
       def docker(*args)
         args.compact.unshift :docker
       end
 
+      def git(*args, path: nil)
+        [ :git, *([ "-C", path ] if path), *args.compact ]
+      end
+
       def tags(**details)
-        Mrsk::Tags.from_config(config, **details)
+        Kamal::Tags.from_config(config, **details)
       end
   end
 end

lib/kamal/commands/builder.rb

@@ -0,0 +1,82 @@
+require "active_support/core_ext/string/filters"
+
+class Kamal::Commands::Builder < Kamal::Commands::Base
+  delegate :create, :remove, :push, :clean, :pull, :info, :validate_image, to: :target
+  delegate :clone_directory, :build_directory, to: :"config.builder"
+
+  def name
+    target.class.to_s.remove("Kamal::Commands::Builder::").underscore.inquiry
+  end
+
+  def target
+    case
+    when !config.builder.multiarch? && !config.builder.cached?
+      native
+    when !config.builder.multiarch? && config.builder.cached?
+      native_cached
+    when config.builder.local? && config.builder.remote?
+      multiarch_remote
+    when config.builder.remote?
+      native_remote
+    else
+      multiarch
+    end
+  end
+
+  def native
+    @native ||= Kamal::Commands::Builder::Native.new(config)
+  end
+
+  def native_cached
+    @native ||= Kamal::Commands::Builder::Native::Cached.new(config)
+  end
+
+  def native_remote
+    @native ||= Kamal::Commands::Builder::Native::Remote.new(config)
+  end
+
+  def multiarch
+    @multiarch ||= Kamal::Commands::Builder::Multiarch.new(config)
+  end
+
+  def multiarch_remote
+    @multiarch_remote ||= Kamal::Commands::Builder::Multiarch::Remote.new(config)
+  end
+
+
+  def ensure_local_dependencies_installed
+    if name.native?
+      ensure_local_docker_installed
+    else
+      combine \
+        ensure_local_docker_installed,
+        ensure_local_buildx_installed
+    end
+  end
+
+  def create_clone_directory
+    make_directory clone_directory
+  end
+
+  def clone
+    git :clone, Kamal::Git.root, path: clone_directory
+  end
+
+  def clone_reset_steps
+    [
+      git(:remote, "set-url", :origin, Kamal::Git.root, path: build_directory),
+      git(:fetch, :origin, path: build_directory),
+      git(:reset, "--hard", Kamal::Git.revision, path: build_directory),
+      git(:clean, "-fdx", path: build_directory)
+    ]
+  end
+
+  private
+    def ensure_local_docker_installed
+      docker "--version"
+    end
+
+    def ensure_local_buildx_installed
+      docker :buildx, "version"
+    end
+end

lib/kamal/commands/builder/base.rb

@@ -1,9 +1,9 @@
 
-class Mrsk::Commands::Builder::Base < Mrsk::Commands::Base
+class Kamal::Commands::Builder::Base < Kamal::Commands::Base
   class BuilderError < StandardError; end
 
-  delegate :argumentize, to: Mrsk::Utils
+  delegate :argumentize, to: Kamal::Utils
-  delegate :args, :secrets, :dockerfile, :local_arch, :local_host, :remote_arch, :remote_host, :cache_from, :cache_to, to: :builder_config
+  delegate :args, :secrets, :dockerfile, :target, :local_arch, :local_host, :remote_arch, :remote_host, :cache_from, :cache_to, :ssh, to: :builder_config
 
   def clean
     docker :image, :rm, "--force", config.absolute_image
@@ -14,13 +14,22 @@ class Mrsk::Commands::Builder::Base < Mrsk::Commands::Base
   end
 
   def build_options
-    [ *build_tags, *build_cache, *build_labels, *build_args, *build_secrets, *build_dockerfile ]
+    [ *build_tags, *build_cache, *build_labels, *build_args, *build_secrets, *build_dockerfile, *build_target, *build_ssh ]
   end
 
   def build_context
     config.builder.context
   end
 
+  def validate_image
+    pipe \
+      docker(:inspect, "-f", "'{{ .Config.Labels.service }}'", config.absolute_image),
+      any(
+        [ :grep, "-x", config.service ],
+        "(echo \"Image #{config.absolute_image} is missing the 'service' label\" && exit 1)"
+      )
+  end
+
 
   private
     def build_tags
@@ -29,8 +38,8 @@ class Mrsk::Commands::Builder::Base < Mrsk::Commands::Base
 
     def build_cache
       if cache_to && cache_from
-        ["--cache-to", cache_to,
+        [ "--cache-to", cache_to,
-          "--cache-from", cache_from]
+          "--cache-from", cache_from ]
       end
     end
 
@@ -54,6 +63,14 @@ class Mrsk::Commands::Builder::Base < Mrsk::Commands::Base
       end
     end
 
+    def build_target
+      argumentize "--target", target if target.present?
+    end
+
+    def build_ssh
+      argumentize "--ssh", ssh if ssh.present?
+    end
+
     def builder_config
       config.builder
     end

lib/kamal/commands/builder/multiarch.rb

@@ -1,4 +1,4 @@
-class Mrsk::Commands::Builder::Multiarch < Mrsk::Commands::Builder::Base
+class Kamal::Commands::Builder::Multiarch < Kamal::Commands::Builder::Base
   def create
     docker :buildx, :create, "--use", "--name", builder_name
   end
@@ -7,23 +7,31 @@ class Mrsk::Commands::Builder::Multiarch < Mrsk::Commands::Builder::Base
     docker :buildx, :rm, builder_name
   end
 
-  def push
-    docker :buildx, :build,
-      "--push",
-      "--platform", "linux/amd64,linux/arm64",
-      "--builder", builder_name,
-      *build_options,
-      build_context
-  end
-
   def info
     combine \
       docker(:context, :ls),
       docker(:buildx, :ls)
   end
 
+  def push
+    docker :buildx, :build,
+      "--push",
+      "--platform", platform_names,
+      "--builder", builder_name,
+      *build_options,
+      build_context
+  end
+
   private
     def builder_name
-      "mrsk-#{config.service}-multiarch"
+      "kamal-#{config.service}-multiarch"
+    end
+
+    def platform_names
+      if local_arch
+        "linux/#{local_arch}"
+      else
+        "linux/amd64,linux/arm64"
+      end
     end
 end

lib/kamal/commands/builder/multiarch/remote.rb

@@ -1,4 +1,4 @@
-class Mrsk::Commands::Builder::Multiarch::Remote < Mrsk::Commands::Builder::Multiarch
+class Kamal::Commands::Builder::Multiarch::Remote < Kamal::Commands::Builder::Multiarch
   def create
     combine \
       create_contexts,

lib/kamal/commands/builder/native.rb

@@ -1,4 +1,4 @@
-class Mrsk::Commands::Builder::Native < Mrsk::Commands::Builder::Base
+class Kamal::Commands::Builder::Native < Kamal::Commands::Builder::Base
   def create
     # No-op on native without cache
   end
@@ -7,14 +7,14 @@ class Mrsk::Commands::Builder::Native < Mrsk::Commands::Builder::Base
     # No-op on native without cache
   end
 
+  def info
+    # No-op on native
+  end
+
   def push
     combine \
       docker(:build, *build_options, build_context),
       docker(:push, config.absolute_image),
       docker(:push, config.latest_image)
   end
-
-  def info
-    # No-op on native
-  end
 end

lib/kamal/commands/builder/native/cached.rb

@@ -1,4 +1,4 @@
-class Mrsk::Commands::Builder::Native::Cached < Mrsk::Commands::Builder::Native
+class Kamal::Commands::Builder::Native::Cached < Kamal::Commands::Builder::Native
   def create
     docker :buildx, :create, "--use", "--driver=docker-container"
   end

lib/kamal/commands/builder/native/remote.rb

@@ -1,4 +1,4 @@
-class Mrsk::Commands::Builder::Native::Remote < Mrsk::Commands::Builder::Native
+class Kamal::Commands::Builder::Native::Remote < Kamal::Commands::Builder::Native
   def create
     chain \
       create_context,
@@ -11,25 +11,25 @@ class Mrsk::Commands::Builder::Native::Remote < Mrsk::Commands::Builder::Native
       remove_buildx
   end
 
-  def push
-    docker :buildx, :build,
-      "--push",
-      "--platform", platform,
-      "--builder", builder_name,
-      *build_options,
-      build_context
-  end
-
   def info
     chain \
       docker(:context, :ls),
       docker(:buildx, :ls)
   end
 
+  def push
+    docker :buildx, :build,
+    "--push",
+    "--platform", platform,
+    "--builder", builder_name,
+    *build_options,
+    build_context
+  end
+
 
   private
     def builder_name
-      "mrsk-#{config.service}-native-remote"
+      "kamal-#{config.service}-native-remote"
     end
 
     def builder_name_with_arch

lib/kamal/commands/docker.rb

@@ -1,7 +1,7 @@
-class Mrsk::Commands::Docker < Mrsk::Commands::Base
+class Kamal::Commands::Docker < Kamal::Commands::Base
   # Install Docker using the https://github.com/docker/docker-install convenience script.
   def install
-    pipe [ :curl, "-fsSL", "https://get.docker.com" ], :sh
+    pipe get_docker, :sh
   end
 
   # Checks the Docker client version. Fails if Docker is not installed.
@@ -16,6 +16,15 @@ class Mrsk::Commands::Docker < Mrsk::Commands::Base
 
   # Do we have superuser access to install Docker and start system services?
   def superuser?
-    [ '[ "${EUID:-$(id -u)}" -eq 0 ]' ]
+    [ '[ "${EUID:-$(id -u)}" -eq 0 ] || command -v sudo >/dev/null || command -v su >/dev/null' ]
   end
+
+  private
+    def get_docker
+      shell \
+        any \
+          [ :curl, "-fsSL", "https://get.docker.com" ],
+          [ :wget, "-O -", "https://get.docker.com" ],
+          [ :echo, "\"exit 1\"" ]
+    end
 end

lib/kamal/commands/hook.rb

@@ -1,4 +1,4 @@
-class Mrsk::Commands::Hook < Mrsk::Commands::Base
+class Kamal::Commands::Hook < Kamal::Commands::Base
   def run(hook, **details)
     [ hook_file(hook), env: tags(**details).env ]
   end
@@ -9,6 +9,6 @@ class Mrsk::Commands::Hook < Mrsk::Commands::Base
 
   private
     def hook_file(hook)
-      "#{config.hooks_path}/#{hook}"
+      File.join(config.hooks_path, hook)
     end
 end

lib/kamal/commands/lock.rb

@@ -1,17 +1,18 @@
 require "active_support/duration"
 require "time"
+require "base64"
 
-class Mrsk::Commands::Lock < Mrsk::Commands::Base
+class Kamal::Commands::Lock < Kamal::Commands::Base
   def acquire(message, version)
     combine \
-      [:mkdir, lock_dir],
+      [ :mkdir, lock_dir ],
       write_lock_details(message, version)
   end
 
   def release
     combine \
-      [:rm, lock_details_file],
+      [ :rm, lock_details_file ],
-      [:rm, "-r", lock_dir]
+      [ :rm, "-r", lock_dir ]
   end
 
   def status
@@ -20,31 +21,41 @@ class Mrsk::Commands::Lock < Mrsk::Commands::Base
       read_lock_details
   end
 
+  def ensure_locks_directory
+    [ :mkdir, "-p", locks_dir ]
+  end
+
   private
     def write_lock_details(message, version)
       write \
-        [:echo, "\"#{Base64.encode64(lock_details(message, version))}\""],
+        [ :echo, "\"#{Base64.encode64(lock_details(message, version))}\"" ],
         lock_details_file
     end
 
     def read_lock_details
       pipe \
-        [:cat, lock_details_file],
+        [ :cat, lock_details_file ],
-        [:base64, "-d"]
+        [ :base64, "-d" ]
     end
 
     def stat_lock_dir
       write \
-        [:stat, lock_dir],
+        [ :stat, lock_dir ],
         "/dev/null"
     end
 
+    def locks_dir
+      File.join(config.run_directory, "locks")
+    end
+
     def lock_dir
-      "mrsk_lock-#{config.service}"
+      dir_name = [ config.service, config.destination ].compact.join("-")
+
+      File.join(locks_dir, dir_name)
     end
 
     def lock_details_file
-      [lock_dir, :details].join("/")
+      File.join(lock_dir, "details")
     end
 
     def lock_details(message, version)
@@ -56,7 +67,7 @@ class Mrsk::Commands::Lock < Mrsk::Commands::Base
     end
 
     def locked_by
-      `git config user.name`.strip
+      Kamal::Git.user_name
     rescue Errno::ENOENT
       "Unknown"
     end

lib/kamal/commands/proxy.rb

@@ -0,0 +1,79 @@
+class Kamal::Commands::Proxy < Kamal::Commands::Base
+  delegate :argumentize, :optionize, to: Kamal::Utils
+  delegate :container_name, to: :proxy_config
+
+  attr_reader :proxy_config
+
+  def initialize(config)
+    super
+    @proxy_config = config.proxy
+  end
+
+  def run
+    docker :run,
+      "--name", container_name,
+      "--detach",
+      "--restart", "unless-stopped",
+      *proxy_config.publish_args,
+      "--volume", "/var/run/docker.sock:/var/run/docker.sock",
+      "--volume", "#{container_name}:/root/.config/parachute",
+      *config.logging_args,
+      *proxy_config.docker_options_args,
+      proxy_config.image
+  end
+
+  def start
+    docker :container, :start, container_name
+  end
+
+  def stop
+    docker :container, :stop, container_name
+  end
+
+  def start_or_run
+    combine start, run, by: "||"
+  end
+
+  def deploy(service, target:)
+    optionize({ target: target })
+    docker :exec, container_name, :parachute, :deploy, service, *optionize({ target: target }), *proxy_config.deploy_command_args
+  end
+
+  def remove(service, target:)
+    docker :exec, container_name, :parachute, :remove, service, *optionize({ target: target })
+  end
+
+  def info
+    docker :ps, "--filter", "name=^#{container_name}$"
+  end
+
+  def logs(since: nil, lines: nil, grep: nil)
+    pipe \
+      docker(:logs, container_name, (" --since #{since}" if since), (" --tail #{lines}" if lines), "--timestamps", "2>&1"),
+      ("grep '#{grep}'" if grep)
+  end
+
+  def follow_logs(host:, grep: nil)
+    run_over_ssh pipe(
+      docker(:logs, container_name, "--timestamps", "--tail", "10", "--follow", "2>&1"),
+      (%(grep "#{grep}") if grep)
+    ).join(" "), host: host
+  end
+
+  def remove_container
+    docker :container, :prune, "--force", "--filter", container_filter
+  end
+
+  def remove_image
+    docker :image, :prune, "--all", "--force", "--filter", image_filter
+  end
+
+  private
+    def container_filter
+      "label=org.opencontainers.image.title=parachute"
+    end
+
+    def image_filter
+      "label=org.opencontainers.image.title=parachute"
+    end
+end

lib/kamal/commands/prune.rb

@@ -1,9 +1,9 @@
 require "active_support/duration"
 require "active_support/core_ext/numeric/time"
 
-class Mrsk::Commands::Prune < Mrsk::Commands::Base
+class Kamal::Commands::Prune < Kamal::Commands::Base
   def dangling_images
-    docker :image, :prune, "--force", "--filter", "label=service=#{config.service}", "--filter", "dangling=true"
+    docker :image, :prune, "--force", "--filter", "label=service=#{config.service}"
   end
 
   def tagged_images
@@ -13,16 +13,16 @@ class Mrsk::Commands::Prune < Mrsk::Commands::Base
       "while read image tag; do docker rmi $tag; done"
   end
 
-  def containers(keep_last: 5)
+  def app_containers(retain:)
     pipe \
       docker(:ps, "-q", "-a", *service_filter, *stopped_containers_filters),
-      "tail -n +#{keep_last + 1}",
+      "tail -n +#{retain + 1}",
       "while read container_id; do docker rm $container_id; done"
   end
 
   private
     def stopped_containers_filters
-      [ "created", "exited", "dead" ].flat_map { |status| ["--filter", "status=#{status}"] }
+      [ "created", "exited", "dead" ].flat_map { |status| [ "--filter", "status=#{status}" ] }
     end
 
     def active_image_list

lib/kamal/commands/registry.rb

@@ -1,8 +1,11 @@
-class Mrsk::Commands::Registry < Mrsk::Commands::Base
+class Kamal::Commands::Registry < Kamal::Commands::Base
   delegate :registry, to: :config
 
   def login
-    docker :login, registry["server"], "-u", sensitive(lookup("username")), "-p", sensitive(lookup("password"))
+    docker :login,
+      registry["server"],
+      "-u", sensitive(Kamal::Utils.escape_shell_value(lookup("username"))),
+      "-p", sensitive(Kamal::Utils.escape_shell_value(lookup("password")))
   end
 
   def logout

lib/kamal/commands/server.rb

@@ -0,0 +1,5 @@
+class Kamal::Commands::Server < Kamal::Commands::Base
+  def ensure_run_directory
+    [ :mkdir, "-p", config.run_directory ]
+  end
+end

lib/kamal/configuration.rb

@@ -0,0 +1,342 @@
+require "active_support/ordered_options"
+require "active_support/core_ext/string/inquiry"
+require "active_support/core_ext/module/delegation"
+require "pathname"
+require "erb"
+require "net/ssh/proxy/jump"
+
+class Kamal::Configuration
+  delegate :service, :image, :port, :servers, :labels, :registry, :stop_wait_time, :hooks_path, :logging, to: :raw_config, allow_nil: true
+  delegate :argumentize, :optionize, to: Kamal::Utils
+
+  attr_reader :destination, :raw_config
+
+  class << self
+    def create_from(config_file:, destination: nil, version: nil)
+      raw_config = load_config_files(config_file, *destination_config_file(config_file, destination))
+
+      new raw_config, destination: destination, version: version
+    end
+
+    private
+      def load_config_files(*files)
+        files.inject({}) { |config, file| config.deep_merge! load_config_file(file) }
+      end
+
+      def load_config_file(file)
+        if file.exist?
+          # Newer Psych doesn't load aliases by default
+          load_method = YAML.respond_to?(:unsafe_load) ? :unsafe_load : :load
+          YAML.send(load_method, ERB.new(IO.read(file)).result).symbolize_keys
+        else
+          raise "Configuration file not found in #{file}"
+        end
+      end
+
+      def destination_config_file(base_config_file, destination)
+        base_config_file.sub_ext(".#{destination}.yml") if destination
+      end
+  end
+
+  def initialize(raw_config, destination: nil, version: nil, validate: true)
+    @raw_config = ActiveSupport::InheritableOptions.new(raw_config)
+    @destination = destination
+    @declared_version = version
+    valid? if validate
+  end
+
+
+  def version=(version)
+    @declared_version = version
+  end
+
+  def version
+    @declared_version.presence || ENV["VERSION"] || git_version
+  end
+
+  def abbreviated_version
+    if version
+      # Don't abbreviate <sha>_uncommitted_<etc>
+      if version.include?("_")
+        version
+      else
+        version[0...7]
+      end
+    end
+  end
+
+  def minimum_version
+    raw_config.minimum_version
+  end
+
+
+  def roles
+    @roles ||= role_names.collect { |role_name| Role.new(role_name, config: self) }
+  end
+
+  def role(name)
+    roles.detect { |r| r.name == name.to_s }
+  end
+
+  def accessories
+    @accessories ||= raw_config.accessories&.keys&.collect { |name| Kamal::Configuration::Accessory.new(name, config: self) } || []
+  end
+
+  def accessory(name)
+    accessories.detect { |a| a.name == name.to_s }
+  end
+
+
+  def all_hosts
+    (roles + accessories).flat_map(&:hosts).uniq
+  end
+
+  def primary_host
+    primary_role&.primary_host
+  end
+
+  def primary_role_name
+    raw_config.primary_role || "web"
+  end
+
+  def primary_role
+    role(primary_role_name)
+  end
+
+  def allow_empty_roles?
+    raw_config.allow_empty_roles
+  end
+
+  def proxy_roles
+    roles.select(&:running_proxy?)
+  end
+
+  def proxy_role_names
+    proxy_roles.flat_map(&:name)
+  end
+
+  def proxy_hosts
+    proxy_roles.flat_map(&:hosts).uniq
+  end
+
+  def repository
+    [ raw_config.registry["server"], image ].compact.join("/")
+  end
+
+  def absolute_image
+    "#{repository}:#{version}"
+  end
+
+  def latest_image
+    "#{repository}:#{latest_tag}"
+  end
+
+  def latest_tag
+    [ "latest", *destination ].join("-")
+  end
+
+  def service_with_version
+    "#{service}-#{version}"
+  end
+
+  def require_destination?
+    raw_config.require_destination
+  end
+
+  def retain_containers
+    raw_config.retain_containers || 5
+  end
+
+
+  def volume_args
+    if raw_config.volumes.present?
+      argumentize "--volume", raw_config.volumes
+    else
+      []
+    end
+  end
+
+  def logging_args
+    if logging.present?
+      optionize({ "log-driver" => logging["driver"] }.compact) +
+        argumentize("--log-opt", logging["options"])
+    else
+      argumentize("--log-opt", { "max-size" => "10m" })
+    end
+  end
+
+
+  def boot
+    Kamal::Configuration::Boot.new(config: self)
+  end
+
+  def builder
+    Kamal::Configuration::Builder.new(config: self)
+  end
+
+  def proxy
+    Kamal::Configuration::Proxy.new(config: self)
+  end
+
+  def ssh
+    Kamal::Configuration::Ssh.new(config: self)
+  end
+
+  def sshkit
+    Kamal::Configuration::Sshkit.new(config: self)
+  end
+
+
+  def readiness_delay
+    raw_config.readiness_delay || 7
+  end
+
+  def run_id
+    @run_id ||= SecureRandom.hex(16)
+  end
+
+
+  def run_directory
+    raw_config.run_directory || ".kamal"
+  end
+
+  def run_directory_as_docker_volume
+    if Pathname.new(run_directory).absolute?
+      run_directory
+    else
+      File.join "$(pwd)", run_directory
+    end
+  end
+
+  def hooks_path
+    raw_config.hooks_path || ".kamal/hooks"
+  end
+
+  def asset_path
+    raw_config.asset_path
+  end
+
+
+  def host_env_directory
+    File.join(run_directory, "env")
+  end
+
+  def env
+    raw_config.env || {}
+  end
+
+  def env_tags
+    @env_tags ||= if (tags = raw_config.env["tags"])
+      tags.collect { |name, config| Kamal::Configuration::Env::Tag.new(name, config: config) }
+    else
+      []
+    end
+  end
+
+  def env_tag(name)
+    env_tags.detect { |t| t.name == name.to_s }
+  end
+
+
+  def valid?
+    ensure_destination_if_required && ensure_required_keys_present && ensure_valid_kamal_version && ensure_retain_containers_valid && ensure_valid_service_name
+  end
+
+  def to_h
+    {
+      roles: role_names,
+      hosts: all_hosts,
+      primary_host: primary_host,
+      version: version,
+      repository: repository,
+      absolute_image: absolute_image,
+      service_with_version: service_with_version,
+      volume_args: volume_args,
+      ssh_options: ssh.to_h,
+      sshkit: sshkit.to_h,
+      builder: builder.to_h,
+      accessories: raw_config.accessories,
+      logging: logging_args
+    }.compact
+  end
+
+
+  private
+    # Will raise ArgumentError if any required config keys are missing
+    def ensure_destination_if_required
+      if require_destination? && destination.nil?
+        raise ArgumentError, "You must specify a destination"
+      end
+
+      true
+    end
+
+    def ensure_required_keys_present
+      %i[ service image registry servers ].each do |key|
+        raise ArgumentError, "Missing required configuration for #{key}" unless raw_config[key].present?
+      end
+
+      if raw_config.registry["username"].blank?
+        raise ArgumentError, "You must specify a username for the registry in config/deploy.yml"
+      end
+
+      if raw_config.registry["password"].blank?
+        raise ArgumentError, "You must specify a password for the registry in config/deploy.yml (or set the ENV variable if that's used)"
+      end
+
+      unless role_names.include?(primary_role_name)
+        raise ArgumentError, "The primary_role #{primary_role_name} isn't defined"
+      end
+
+      if primary_role.hosts.empty?
+        raise ArgumentError, "No servers specified for the #{primary_role.name} primary_role"
+      end
+
+      unless allow_empty_roles?
+        roles.each do |role|
+          if role.hosts.empty?
+            raise ArgumentError, "No servers specified for the #{role.name} role. You can ignore this with allow_empty_roles: true"
+          end
+        end
+      end
+
+      true
+    end
+
+    def ensure_valid_service_name
+      raise ArgumentError, "Service name can only include alphanumeric characters, hyphens, and underscores" unless raw_config[:service] =~ /^[a-z0-9_-]+$/i
+
+      true
+    end
+
+    def ensure_valid_kamal_version
+      if minimum_version && Gem::Version.new(minimum_version) > Gem::Version.new(Kamal::VERSION)
+        raise ArgumentError, "Current version is #{Kamal::VERSION}, minimum required is #{minimum_version}"
+      end
+
+      true
+    end
+
+    def ensure_retain_containers_valid
+      raise ArgumentError, "Must retain at least 1 container" if retain_containers < 1
+
+      true
+    end
+
+
+    def role_names
+      raw_config.servers.is_a?(Array) ? [ "web" ] : raw_config.servers.keys.sort
+    end
+
+    def git_version
+      @git_version ||=
+        if Kamal::Git.used?
+          if Kamal::Git.uncommitted_changes.present? && !builder.git_clone?
+            uncommitted_suffix = "_uncommitted_#{SecureRandom.hex(8)}"
+          end
+          [ Kamal::Git.revision, uncommitted_suffix ].compact.join
+        else
+          raise "Can't use commit hash as version, no git repository found in #{Dir.pwd}"
+        end
+    end
+end

lib/kamal/configuration/accessory.rb

@@ -1,5 +1,5 @@
-class Mrsk::Configuration::Accessory
+class Kamal::Configuration::Accessory
-  delegate :argumentize, :argumentize_env_with_secrets, :optionize, to: Mrsk::Utils
+  delegate :argumentize, :optionize, to: Kamal::Utils
 
   attr_accessor :name, :specifics
 
@@ -8,7 +8,7 @@ class Mrsk::Configuration::Accessory
   end
 
   def service_name
-    "#{config.service}-#{name}"
+    specifics["service"] || "#{config.service}-#{name}"
   end
 
   def image
@@ -16,7 +16,7 @@ class Mrsk::Configuration::Accessory
   end
 
   def hosts
-    if (specifics.keys & ["host", "hosts", "roles"]).size != 1
+    if (specifics.keys & [ "host", "hosts", "roles" ]).size != 1
       raise ArgumentError, "Specify one of `host`, `hosts` or `roles` for accessory `#{name}`"
     end
 
@@ -42,11 +42,13 @@ class Mrsk::Configuration::Accessory
   end
 
   def env
-    specifics["env"] || {}
+    Kamal::Configuration::Env.from_config \
+      config: specifics.fetch("env", {}),
+      secrets_file: File.join(config.host_env_directory, "accessories", "#{service_name}.env")
   end
 
   def env_args
-    argumentize_env_with_secrets env
+    env.args
   end
 
   def files
@@ -58,8 +60,8 @@ class Mrsk::Configuration::Accessory
 
   def directories
     specifics["directories"]&.to_h do |host_to_container_mapping|
-      host_relative_path, container_path = host_to_container_mapping.split(":")
+      host_path, container_path = host_to_container_mapping.split(":")
-      [ expand_host_path(host_relative_path), container_path ]
+      [ expand_host_path(host_path), container_path ]
     end || {}
   end
 
@@ -99,10 +101,10 @@ class Mrsk::Configuration::Accessory
     end
 
     def with_clear_env_loaded
-      (env["clear"] || env).each { |k, v| ENV[k] = v }
+      env.clear.each { |k, v| ENV[k] = v }
       yield
     ensure
-      (env["clear"] || env).each { |k, v| ENV.delete(k) }
+      env.clear.each { |k, v| ENV.delete(k) }
     end
 
     def read_dynamic_file(local_file)
@@ -126,13 +128,17 @@ class Mrsk::Configuration::Accessory
 
     def remote_directories_as_volumes
       specifics["directories"]&.collect do |host_to_container_mapping|
-        host_relative_path, container_path = host_to_container_mapping.split(":")
+        host_path, container_path = host_to_container_mapping.split(":")
-        [ expand_host_path(host_relative_path), container_path ].join(":")
+        [ expand_host_path(host_path), container_path ].join(":")
       end || []
     end
 
-    def expand_host_path(host_relative_path)
+    def expand_host_path(host_path)
-      "#{service_data_directory}/#{host_relative_path}"
+      absolute_path?(host_path) ? host_path : File.join(service_data_directory, host_path)
+    end
+
+    def absolute_path?(path)
+      Pathname.new(path).absolute?
     end
 
     def service_data_directory
@@ -143,7 +149,7 @@ class Mrsk::Configuration::Accessory
       if specifics.key?("host")
         host = specifics["host"]
         if host
-          [host]
+          [ host ]
         else
           raise ArgumentError, "Missing host for accessory `#{name}`"
         end

lib/kamal/configuration/boot.rb

@@ -1,4 +1,4 @@
-class Mrsk::Configuration::Boot
+class Kamal::Configuration::Boot
   def initialize(config:)
     @options = config.raw_config.boot || {}
     @host_count = config.all_hosts.count
@@ -8,7 +8,7 @@ class Mrsk::Configuration::Boot
     limit = @options["limit"]
 
     if limit.to_s.end_with?("%")
-      @host_count * limit.to_i / 100
+      [ @host_count * limit.to_i / 100, 1 ].max
     else
       limit
     end

lib/kamal/configuration/builder.rb

@@ -1,8 +1,10 @@
-class Mrsk::Configuration::Builder
+class Kamal::Configuration::Builder
   def initialize(config:)
     @options = config.raw_config.builder || {}
     @image = config.image
     @server = config.registry["server"]
+    @service = config.service
+    @destination = config.destination
 
     valid?
   end
@@ -39,6 +41,10 @@ class Mrsk::Configuration::Builder
     @options["dockerfile"] || "Dockerfile"
   end
 
+  def target
+    @options["target"]
+  end
+
   def context
     @options["context"] || "."
   end
@@ -81,14 +87,31 @@ class Mrsk::Configuration::Builder
     end
   end
 
+  def ssh
+    @options["ssh"]
+  end
+
+  def git_clone?
+    Kamal::Git.used? && @options["context"].nil?
+  end
+
+  def clone_directory
+    @clone_directory ||= File.join Dir.tmpdir, "kamal-clones", [ @service, pwd_sha ].compact.join("-")
+  end
+
+  def build_directory
+    @build_directory ||=
+      if git_clone?
+        File.join clone_directory, repo_basename, repo_relative_pwd
+      else
+        "."
+      end
+  end
+
   private
     def valid?
-      if @options["local"] && !@options["remote"]
-        raise ArgumentError, "You must specify both local and remote builder config for remote multiarch builds"
-      end
-
       if @options["cache"] && @options["cache"]["type"]
-        raise ArgumentError, "Invalid cache type: #{@options["cache"]["type"]}" unless ["gha", "registry"].include?(@options["cache"]["type"])
+        raise ArgumentError, "Invalid cache type: #{@options["cache"]["type"]}" unless [ "gha", "registry" ].include?(@options["cache"]["type"])
       end
     end
 
@@ -96,19 +119,35 @@ class Mrsk::Configuration::Builder
       @options["cache"]&.fetch("image", nil) || "#{@image}-build-cache"
     end
 
+    def cache_image_ref
+      [ @server, cache_image ].compact.join("/")
+    end
+
     def cache_from_config_for_gha
       "type=gha"
     end
 
     def cache_from_config_for_registry
-      [ "type=registry", "ref=#{@server}/#{cache_image}" ].compact.join(",")
+      [ "type=registry", "ref=#{cache_image_ref}" ].compact.join(",")
     end
 
     def cache_to_config_for_gha
-      [ "type=gha", @options["cache"]&.fetch("options", nil)].compact.join(",")
+      [ "type=gha", @options["cache"]&.fetch("options", nil) ].compact.join(",")
     end
 
     def cache_to_config_for_registry
-      [ "type=registry", @options["cache"]&.fetch("options", nil), "ref=#{@server}/#{cache_image}" ].compact.join(",")
+      [ "type=registry", @options["cache"]&.fetch("options", nil), "ref=#{cache_image_ref}" ].compact.join(",")
+    end
+
+    def repo_basename
+      File.basename(Kamal::Git.root)
+    end
+
+    def repo_relative_pwd
+      Dir.pwd.delete_prefix(Kamal::Git.root)
+    end
+
+    def pwd_sha
+      Digest::SHA256.hexdigest(Dir.pwd)[0..12]
     end
 end

lib/kamal/configuration/env.rb

@@ -0,0 +1,40 @@
+class Kamal::Configuration::Env
+  attr_reader :secrets_keys, :clear, :secrets_file
+  delegate :argumentize, to: Kamal::Utils
+
+  def self.from_config(config:, secrets_file: nil)
+    secrets_keys = config.fetch("secret", [])
+    clear = config.fetch("clear", config.key?("secret") || config.key?("tags") ? {} : config)
+
+    new clear: clear, secrets_keys: secrets_keys, secrets_file: secrets_file
+  end
+
+  def initialize(clear:, secrets_keys:, secrets_file:)
+    @clear = clear
+    @secrets_keys = secrets_keys
+    @secrets_file = secrets_file
+  end
+
+  def args
+    [ "--env-file", secrets_file, *argumentize("--env", clear) ]
+  end
+
+  def secrets_io
+    StringIO.new(Kamal::EnvFile.new(secrets).to_s)
+  end
+
+  def secrets
+    @secrets ||= secrets_keys.to_h { |key| [ key, ENV.fetch(key) ] }
+  end
+
+  def secrets_directory
+    File.dirname(secrets_file)
+  end
+
+  def merge(other)
+    self.class.new \
+      clear: @clear.merge(other.clear),
+      secrets_keys: @secrets_keys | other.secrets_keys,
+      secrets_file: secrets_file
+  end
+end

lib/kamal/configuration/env/tag.rb

@@ -0,0 +1,12 @@
+class Kamal::Configuration::Env::Tag
+  attr_reader :name, :config
+
+  def initialize(name, config:)
+    @name = name
+    @config = config
+  end
+
+  def env
+    Kamal::Configuration::Env.from_config(config: config)
+  end
+end

lib/kamal/configuration/proxy.rb

@@ -0,0 +1,58 @@
+class Kamal::Configuration::Proxy
+  DEFAULT_HTTP_PORT = 80
+  DEFAULT_HTTPS_PORT = 443
+  DEFAULT_IMAGE = "basecamp/parachute:latest"
+
+  delegate :argumentize, :optionize, to: Kamal::Utils
+
+  def initialize(config:)
+    @options = config.raw_config.proxy || {}
+  end
+
+  def image
+    options.fetch("image", DEFAULT_IMAGE)
+  end
+
+  def debug?
+    !!options[:debug]
+  end
+
+  def http_port
+    if options.key?(:http_port)
+      options[:http_port]
+    elsif !automatic_tls?
+      DEFAULT_HTTP_PORT
+    end
+  end
+
+  def https_port
+    if options.key?(:http_port)
+      options[:http_port]
+    elsif automatic_tls?
+      DEFAULT_HTTPS_PORT
+    end
+  end
+
+  def container_name
+    "parachute_#{http_port}_#{https_port}"
+  end
+
+  def docker_options_args
+    optionize(options.fetch("options", {}))
+  end
+
+  def publish_args
+    argumentize "--publish", *("#{http_port}:80" if http_port), *("#{https_port}:80" if https_port)
+  end
+
+  def deploy_options
+    options.fetch(:deploy, {})
+  end
+
+  def deploy_command_args
+    optionize deploy_options
+  end
+
+  private
+    attr_accessor :options
+end

lib/kamal/configuration/role.rb

@@ -0,0 +1,174 @@
+class Kamal::Configuration::Role
+  delegate :argumentize, :optionize, to: Kamal::Utils
+
+  attr_accessor :name
+  alias to_s name
+
+  def initialize(name, config:)
+    @name, @config = name.inquiry, config
+    @tagged_hosts ||= extract_tagged_hosts_from_config
+  end
+
+  def primary_host
+    hosts.first
+  end
+
+  def hosts
+    tagged_hosts.keys
+  end
+
+  def env_tags(host)
+    tagged_hosts.fetch(host).collect { |tag| config.env_tag(tag) }
+  end
+
+  def cmd
+    specializations["cmd"]
+  end
+
+  def option_args
+    if args = specializations["options"]
+      optionize args
+    else
+      []
+    end
+  end
+
+  def labels
+    default_labels.merge(custom_labels)
+  end
+
+  def label_args
+    argumentize "--label", labels
+  end
+
+  def logging_args
+    args = config.logging || {}
+    args.deep_merge!(specializations["logging"]) if specializations["logging"].present?
+
+    if args.any?
+      optionize({ "log-driver" => args["driver"] }.compact) +
+        argumentize("--log-opt", args["options"])
+    else
+      config.logging_args
+    end
+  end
+
+
+  def env(host)
+    @envs ||= {}
+    @envs[host] ||= [ base_env, specialized_env, *env_tags(host).map(&:env) ].reduce(:merge)
+  end
+
+  def env_args(host)
+    env(host).args
+  end
+
+  def asset_volume_args
+    asset_volume&.docker_args
+  end
+
+
+  def running_proxy?
+    if specializations["proxy"].nil?
+      primary?
+    else
+      specializations["proxy"]
+    end
+  end
+
+  def primary?
+    self == @config.primary_role
+  end
+
+
+  def container_name(version = nil)
+    [ container_prefix, version || config.version ].compact.join("-")
+  end
+
+  def container_prefix
+    [ config.service, name, config.destination ].compact.join("-")
+  end
+
+
+  def asset_path
+    specializations["asset_path"] || config.asset_path
+  end
+
+  def assets?
+    asset_path.present? && running_proxy?
+  end
+
+  def asset_volume(version = nil)
+    if assets?
+      Kamal::Configuration::Volume.new \
+        host_path: asset_volume_path(version), container_path: asset_path
+    end
+  end
+
+  def asset_extracted_path(version = nil)
+    File.join config.run_directory, "assets", "extracted", container_name(version)
+  end
+
+  def asset_volume_path(version = nil)
+    File.join config.run_directory, "assets", "volumes", container_name(version)
+  end
+
+  private
+    attr_accessor :config, :tagged_hosts
+
+    def extract_tagged_hosts_from_config
+      {}.tap do |tagged_hosts|
+        extract_hosts_from_config.map do |host_config|
+          if host_config.is_a?(Hash)
+            raise ArgumentError, "Multiple hosts found: #{host_config.inspect}" unless host_config.size == 1
+
+            host, tags = host_config.first
+            tagged_hosts[host] = Array(tags)
+          elsif host_config.is_a?(String) || host_config.is_a?(Symbol)
+            tagged_hosts[host_config] = []
+          else
+            raise ArgumentError, "Invalid host config: #{host_config.inspect}"
+          end
+        end
+      end
+    end
+
+    def extract_hosts_from_config
+      if config.servers.is_a?(Array)
+        config.servers
+      else
+        servers = config.servers[name]
+        servers.is_a?(Array) ? servers : Array(servers["hosts"])
+      end
+    end
+
+    def default_labels
+      { "service" => config.service, "role" => name, "destination" => config.destination }
+    end
+
+    def custom_labels
+      Hash.new.tap do |labels|
+        labels.merge!(config.labels) if config.labels.present?
+        labels.merge!(specializations["labels"]) if specializations["labels"].present?
+      end
+    end
+
+    def specializations
+      if config.servers.is_a?(Array) || config.servers[name].is_a?(Array)
+        {}
+      else
+        config.servers[name].except("hosts")
+      end
+    end
+
+    def specialized_env
+      Kamal::Configuration::Env.from_config config: specializations.fetch("env", {})
+    end
+
+    # Secrets are stored in an array, which won't merge by default, so have to do it by hand.
+    def base_env
+      Kamal::Configuration::Env.from_config \
+        config: config.env,
+        secrets_file: File.join(config.host_env_directory, "roles", "#{container_prefix}.env")
+    end
+end

lib/kamal/configuration/ssh.rb

@@ -0,0 +1,42 @@
+class Kamal::Configuration::Ssh
+  LOGGER = ::Logger.new(STDERR)
+
+  def initialize(config:)
+    @config = config.raw_config.ssh || {}
+  end
+
+  def user
+    config.fetch("user", "root")
+  end
+
+  def port
+    config.fetch("port", 22)
+  end
+
+  def proxy
+    if (proxy = config["proxy"])
+      Net::SSH::Proxy::Jump.new(proxy.include?("@") ? proxy : "root@#{proxy}")
+    elsif (proxy_command = config["proxy_command"])
+      Net::SSH::Proxy::Command.new(proxy_command)
+    end
+  end
+
+  def options
+    { user: user, port: port, proxy: proxy, logger: logger, keepalive: true, keepalive_interval: 30 }.compact
+  end
+
+  def to_h
+    options.except(:logger).merge(log_level: log_level)
+  end
+
+  private
+    attr_accessor :config
+
+    def logger
+      LOGGER.tap { |logger| logger.level = log_level }
+    end
+
+    def log_level
+      config.fetch("log_level", :fatal)
+    end
+end

lib/kamal/configuration/sshkit.rb

@@ -0,0 +1,20 @@
+class Kamal::Configuration::Sshkit
+  def initialize(config:)
+    @options = config.raw_config.sshkit || {}
+  end
+
+  def max_concurrent_starts
+    options.fetch("max_concurrent_starts", 30)
+  end
+
+  def pool_idle_timeout
+    options.fetch("pool_idle_timeout", 900)
+  end
+
+  def to_h
+    options
+  end
+
+  private
+    attr_accessor :options
+end

lib/kamal/configuration/volume.rb

@@ -0,0 +1,22 @@
+class Kamal::Configuration::Volume
+  attr_reader :host_path, :container_path
+  delegate :argumentize, to: Kamal::Utils
+
+  def initialize(host_path:, container_path:)
+    @host_path = host_path
+    @container_path = container_path
+  end
+
+  def docker_args
+    argumentize "--volume", "#{host_path_for_docker_volume}:#{container_path}"
+  end
+
+  private
+    def host_path_for_docker_volume
+      if Pathname.new(host_path).absolute?
+        host_path
+      else
+        File.join "$(pwd)", host_path
+      end
+    end
+end

lib/kamal/env_file.rb

@@ -0,0 +1,38 @@
+# Encode an env hash as a string where secret values have been looked up and all values escaped for Docker.
+class Kamal::EnvFile
+  def initialize(env)
+    @env = env
+  end
+
+  def to_s
+    env_file = StringIO.new.tap do |contents|
+      @env.each do |key, value|
+        contents << docker_env_file_line(key, value)
+      end
+    end.string
+
+    # Ensure the file has some contents to avoid the SSHKIT empty file warning
+    env_file.presence || "\n"
+  end
+
+  alias to_str to_s
+
+  private
+    def docker_env_file_line(key, value)
+      "#{key}=#{escape_docker_env_file_value(value)}\n"
+    end
+
+    # Escape a value to make it safe to dump in a docker file.
+    def escape_docker_env_file_value(value)
+      # keep non-ascii(UTF-8) characters as it is
+      value.to_s.scan(/[\x00-\x7F]+|[^\x00-\x7F]+/).map do |part|
+        part.ascii_only? ? escape_docker_env_file_ascii_value(part) : part
+      end.join
+    end
+
+    def escape_docker_env_file_ascii_value(value)
+      # Doublequotes are treated literally in docker env files
+      # so remove leading and trailing ones and unescape any others
+      value.to_s.dump[1..-2].gsub(/\\"/, "\"")
+    end
+end

lib/kamal/git.rb

@@ -0,0 +1,23 @@
+module Kamal::Git
+  extend self
+
+  def used?
+    system("git rev-parse")
+  end
+
+  def user_name
+    `git config user.name`.strip
+  end
+
+  def revision
+    `git rev-parse HEAD`.strip
+  end
+
+  def uncommitted_changes
+    `git status --porcelain`.strip
+  end
+
+  def root
+    `git rev-parse --show-toplevel`.strip
+  end
+end

lib/kamal/sshkit_with_ext.rb

@@ -0,0 +1,141 @@
+require "sshkit"
+require "sshkit/dsl"
+require "net/scp"
+require "active_support/core_ext/hash/deep_merge"
+require "json"
+
+class SSHKit::Backend::Abstract
+  def capture_with_info(*args, **kwargs)
+    capture(*args, **kwargs, verbosity: Logger::INFO)
+  end
+
+  def capture_with_debug(*args, **kwargs)
+    capture(*args, **kwargs, verbosity: Logger::DEBUG)
+  end
+
+  def capture_with_pretty_json(*args, **kwargs)
+    JSON.pretty_generate(JSON.parse(capture(*args, **kwargs)))
+  end
+
+  def puts_by_host(host, output, type: "App")
+    puts "#{type} Host: #{host}\n#{output}\n\n"
+  end
+
+  # Our execution pattern is for the CLI execute args lists returned
+  # from commands, but this doesn't support returning execution options
+  # from the command.
+  #
+  # Support this by using kwargs for CLI options and merging with the
+  # args-extracted options.
+  module CommandEnvMerge
+    private
+
+    # Override to merge options returned by commands in the args list with
+    # options passed by the CLI and pass them along as kwargs.
+    def command(args, options)
+      more_options, args = args.partition { |a| a.is_a? Hash }
+      more_options << options
+
+      build_command(args, **more_options.reduce(:deep_merge))
+    end
+
+    # Destructure options to pluck out env for merge
+    def build_command(args, env: nil, **options)
+      # Rely on native Ruby kwargs precedence rather than explicit Hash merges
+      SSHKit::Command.new(*args, **default_command_options, **options, env: env_for(env))
+    end
+
+    def default_command_options
+      { in: pwd_path, host: @host, user: @user, group: @group }
+    end
+
+    def env_for(env)
+      @env.to_h.merge(env.to_h)
+    end
+  end
+  prepend CommandEnvMerge
+end
+
+class SSHKit::Backend::Netssh::Configuration
+  attr_accessor :max_concurrent_starts
+end
+
+class SSHKit::Backend::Netssh
+  module LimitConcurrentStartsClass
+    attr_reader :start_semaphore
+
+    def configure(&block)
+      super &block
+      # Create this here to avoid lazy creation by multiple threads
+      if config.max_concurrent_starts
+        @start_semaphore = Concurrent::Semaphore.new(config.max_concurrent_starts)
+      end
+    end
+  end
+
+  class << self
+    prepend LimitConcurrentStartsClass
+  end
+
+  module LimitConcurrentStartsInstance
+    private
+      def with_ssh(&block)
+        host.ssh_options = self.class.config.ssh_options.merge(host.ssh_options || {})
+        self.class.pool.with(
+          method(:start_with_concurrency_limit),
+          String(host.hostname),
+          host.username,
+          host.netssh_options,
+          &block
+        )
+      end
+
+      def start_with_concurrency_limit(*args)
+        if self.class.start_semaphore
+          self.class.start_semaphore.acquire do
+            Net::SSH.start(*args)
+          end
+        else
+          Net::SSH.start(*args)
+        end
+      end
+  end
+
+  prepend LimitConcurrentStartsInstance
+end
+
+class SSHKit::Runner::Parallel
+  # SSHKit joins the threads in sequence and fails on the first error it encounters, which means that we wait threads
+  # before the first failure to complete but not for ones after.
+  #
+  # We'll patch it to wait for them all to complete, and to record all the threads that errored so we can see when a
+  # problem occurs on multiple hosts.
+  module CompleteAll
+    def execute
+      threads = hosts.map do |host|
+        Thread.new(host) do |h|
+          backend(h, &block).run
+        rescue ::StandardError => e
+          e2 = SSHKit::Runner::ExecuteError.new e
+          raise e2, "Exception while executing #{host.user ? "as #{host.user}@" : "on host "}#{host}: #{e.message}"
+        end
+      end
+
+      exceptions = []
+      threads.each do |t|
+        begin
+          t.join
+        rescue SSHKit::Runner::ExecuteError => e
+          exceptions << e
+        end
+      end
+      if exceptions.one?
+        raise exceptions.first
+      elsif exceptions.many?
+        raise exceptions.first, [ "Exceptions on #{exceptions.count} hosts:", exceptions.map(&:message) ].join("\n")
+      end
+    end
+  end
+
+  prepend CompleteAll
+end

lib/kamal/tags.rb

@@ -1,6 +1,6 @@
 require "time"
 
-class Mrsk::Tags
+class Kamal::Tags
   attr_reader :config, :tags
 
   class << self
@@ -26,7 +26,7 @@ class Mrsk::Tags
   end
 
   def env
-    tags.transform_keys { |detail| "MRSK_#{detail.upcase}" }
+    tags.transform_keys { |detail| "KAMAL_#{detail.upcase}" }
   end
 
   def to_s

lib/kamal/utils.rb

@@ -1,4 +1,4 @@
-module Mrsk::Utils
+module Kamal::Utils
   extend self
 
   DOLLAR_SIGN_WITHOUT_SHELL_EXPANSION_REGEX = /\$(?!{[^\}]*\})/
@@ -9,23 +9,13 @@ module Mrsk::Utils
       if value.present?
         attr = "#{key}=#{escape_shell_value(value)}"
         attr = self.sensitive(attr, redaction: "#{key}=[REDACTED]") if sensitive
-        [ argument, attr]
+        [ argument, attr ]
       else
         [ argument, key ]
       end
     end
   end
 
-  # Return a list of shell arguments using the same named argument against the passed attributes,
-  # but redacts and expands secrets.
-  def argumentize_env_with_secrets(env)
-    if (secrets = env["secret"]).present?
-      argumentize("-e", secrets.to_h { |key| [ key, ENV.fetch(key) ] }, sensitive: true) + argumentize("-e", env["clear"])
-    else
-      argumentize "-e", env.fetch("clear", env)
-    end
-  end
-
   # Returns a list of shell-dashed option arguments. If the value is true, it's treated like a value-less option.
   def optionize(args, with: nil)
     options = if with
@@ -39,14 +29,14 @@ module Mrsk::Utils
 
   # Flattens a one-to-many structure into an array of two-element arrays each containing a key-value pair
   def flatten_args(args)
-    args.flat_map { |key, value| value.try(:map) { |entry| [key, entry] } || [ [ key, value ] ] }
+    args.flat_map { |key, value| value.try(:map) { |entry| [ key, entry ] } || [ [ key, value ] ] }
   end
 
   # Marks sensitive values for redaction in logs and human-visible output.
   # Pass `redaction:` to change the default `"[REDACTED]"` redaction, e.g.
   # `sensitive "#{arg}=#{secret}", redaction: "#{arg}=xxxx"
   def sensitive(...)
-    Mrsk::Utils::Sensitive.new(...)
+    Kamal::Utils::Sensitive.new(...)
   end
 
   def redacted(value)
@@ -62,19 +52,6 @@ module Mrsk::Utils
     end
   end
 
-  def unredacted(value)
-    case
-    when value.respond_to?(:unredacted)
-      value.unredacted
-    when value.respond_to?(:transform_values)
-      value.transform_values { |value| unredacted value }
-    when value.respond_to?(:map)
-      value.map { |element| unredacted element }
-    else
-      value
-    end
-  end
-
   # Escape a value to make it safe for shell use.
   def escape_shell_value(value)
     value.to_s.dump
@@ -82,15 +59,22 @@ module Mrsk::Utils
       .gsub(DOLLAR_SIGN_WITHOUT_SHELL_EXPANSION_REGEX, '\$')
   end
 
-  # Abbreviate a git revhash for concise display
+  # Apply a list of host or role filters, including wildcard matches
-  def abbreviate_version(version)
+  def filter_specific_items(filters, items)
-    if version
+    matches = []
-      # Don't abbreviate <sha>_uncommitted_<etc>
+
-      if version.include?("_")
+    Array(filters).select do |filter|
-        version
+      matches += Array(items).select do |item|
-      else
+        # Only allow * for a wildcard
-        version[0...7]
+        # items are roles or hosts
+        File.fnmatch(filter, item.to_s, File::FNM_EXTGLOB)
       end
     end
+
+    matches.uniq
+  end
+
+  def stable_sort!(elements, &block)
+    elements.sort_by!.with_index { |element, index| [ block.call(element), index ] }
   end
 end

lib/kamal/utils/sensitive.rb

@@ -1,6 +1,7 @@
 require "active_support/core_ext/module/delegation"
+require "sshkit"
 
-class Mrsk::Utils::Sensitive
+class Kamal::Utils::Sensitive
   # So SSHKit knows to redact these values.
   include SSHKit::Redaction
 

lib/kamal/version.rb

@@ -0,0 +1,3 @@
+module Kamal
+  VERSION = "1.5.2"
+end

lib/mrsk/cli/app.rb

@@ -1,290 +0,0 @@
-class Mrsk::Cli::App < Mrsk::Cli::Base
-  desc "boot", "Boot app on servers (or reboot app if already running)"
-  def boot
-    mutating do
-      hold_lock_on_error do
-        say "Get most recent version available as an image...", :magenta unless options[:version]
-        using_version(version_or_latest) do |version|
-          say "Start container with version #{version} using a #{MRSK.config.readiness_delay}s readiness delay (or reboot if already running)...", :magenta
-
-          on(MRSK.hosts) do
-            execute *MRSK.auditor.record("Tagging #{MRSK.config.absolute_image} as the latest image"), verbosity: :debug
-            execute *MRSK.app.tag_current_as_latest
-          end
-
-          on(MRSK.hosts, **MRSK.boot_strategy) do |host|
-            roles = MRSK.roles_on(host)
-
-            roles.each do |role|
-              app = MRSK.app(role: role)
-              auditor = MRSK.auditor(role: role)
-
-              if capture_with_info(*app.container_id_for_version(version, only_running: true), raise_on_non_zero_exit: false).present?
-                tmp_version = "#{version}_replaced_#{SecureRandom.hex(8)}"
-                info "Renaming container #{version} to #{tmp_version} as already deployed on #{host}"
-                execute *auditor.record("Renaming container #{version} to #{tmp_version}"), verbosity: :debug
-                execute *app.rename_container(version: version, new_version: tmp_version)
-              end
-
-              execute *auditor.record("Booted app version #{version}"), verbosity: :debug
-
-              old_version = capture_with_info(*app.current_running_version, raise_on_non_zero_exit: false).strip
-              execute *app.start_or_run(hostname: "#{host}-#{SecureRandom.hex(6)}")
-
-              Mrsk::Utils::HealthcheckPoller.wait_for_healthy(pause_after_ready: true) { capture_with_info(*app.status(version: version)) }
-
-              execute *app.stop(version: old_version), raise_on_non_zero_exit: false if old_version.present?
-            end
-          end
-        end
-      end
-    end
-  end
-
-  desc "start", "Start existing app container on servers"
-  def start
-    mutating do
-      on(MRSK.hosts) do |host|
-        roles = MRSK.roles_on(host)
-
-        roles.each do |role|
-          execute *MRSK.auditor.record("Started app version #{MRSK.config.version}"), verbosity: :debug
-          execute *MRSK.app(role: role).start, raise_on_non_zero_exit: false
-        end
-      end
-    end
-  end
-
-  desc "stop", "Stop app container on servers"
-  def stop
-    mutating do
-      on(MRSK.hosts) do |host|
-        roles = MRSK.roles_on(host)
-
-        roles.each do |role|
-          execute *MRSK.auditor.record("Stopped app", role: role), verbosity: :debug
-          execute *MRSK.app(role: role).stop, raise_on_non_zero_exit: false
-        end
-      end
-    end
-  end
-
-  # FIXME: Drop in favor of just containers?
-  desc "details", "Show details about app containers"
-  def details
-    on(MRSK.hosts) do |host|
-      roles = MRSK.roles_on(host)
-
-      roles.each do |role|
-        puts_by_host host, capture_with_info(*MRSK.app(role: role).info)
-      end
-    end
-  end
-
-  desc "exec [CMD]", "Execute a custom command on servers (use --help to show options)"
-  option :interactive, aliases: "-i", type: :boolean, default: false, desc: "Execute command over ssh for an interactive shell (use for console/bash)"
-  option :reuse, type: :boolean, default: false, desc: "Reuse currently running container instead of starting a new one"
-  def exec(cmd)
-    case
-    when options[:interactive] && options[:reuse]
-      say "Get current version of running container...", :magenta unless options[:version]
-      using_version(options[:version] || current_running_version) do |version|
-        say "Launching interactive command with version #{version} via SSH from existing container on #{MRSK.primary_host}...", :magenta
-        run_locally { exec MRSK.app(role: "web").execute_in_existing_container_over_ssh(cmd, host: MRSK.primary_host) }
-      end
-
-    when options[:interactive]
-      say "Get most recent version available as an image...", :magenta unless options[:version]
-      using_version(version_or_latest) do |version|
-        say "Launching interactive command with version #{version} via SSH from new container on #{MRSK.primary_host}...", :magenta
-        run_locally { exec MRSK.app.execute_in_new_container_over_ssh(cmd, host: MRSK.primary_host) }
-      end
-
-    when options[:reuse]
-      say "Get current version of running container...", :magenta unless options[:version]
-      using_version(options[:version] || current_running_version) do |version|
-        say "Launching command with version #{version} from existing container...", :magenta
-
-        on(MRSK.hosts) do |host|
-          roles = MRSK.roles_on(host)
-
-          roles.each do |role|
-            execute *MRSK.auditor.record("Executed cmd '#{cmd}' on app version #{version}", role: role), verbosity: :debug
-            puts_by_host host, capture_with_info(*MRSK.app(role: role).execute_in_existing_container(cmd))
-          end
-        end
-      end
-
-    else
-      say "Get most recent version available as an image...", :magenta unless options[:version]
-      using_version(version_or_latest) do |version|
-        say "Launching command with version #{version} from new container...", :magenta
-        on(MRSK.hosts) do |host|
-          execute *MRSK.auditor.record("Executed cmd '#{cmd}' on app version #{version}"), verbosity: :debug
-          puts_by_host host, capture_with_info(*MRSK.app.execute_in_new_container(cmd))
-        end
-      end
-    end
-  end
-
-  desc "containers", "Show app containers on servers"
-  def containers
-    on(MRSK.hosts) { |host| puts_by_host host, capture_with_info(*MRSK.app.list_containers) }
-  end
-
-  desc "stale_containers", "Detect app stale containers"
-  option :stop, aliases: "-s", type: :boolean, default: false, desc: "Stop the stale containers found"
-  def stale_containers
-    mutating do
-      stop = options[:stop]
-
-      cli = self
-
-      on(MRSK.hosts) do |host|
-        roles = MRSK.roles_on(host)
-
-        roles.each do |role|
-          cli.send(:stale_versions, host: host, role: role).each do |version|
-            if stop
-              puts_by_host host, "Stopping stale container for role #{role} with version #{version}"
-              execute *MRSK.app(role: role).stop(version: version), raise_on_non_zero_exit: false
-            else
-              puts_by_host host,  "Detected stale container for role #{role} with version #{version} (use `mrsk app stale_containers --stop` to stop)"
-            end
-          end
-        end
-      end
-    end
-  end
-
-  desc "images", "Show app images on servers"
-  def images
-    on(MRSK.hosts) { |host| puts_by_host host, capture_with_info(*MRSK.app.list_images) }
-  end
-
-  desc "logs", "Show log lines from app on servers (use --help to show options)"
-  option :since, aliases: "-s", desc: "Show lines since timestamp (e.g. 2013-01-02T13:23:37Z) or relative (e.g. 42m for 42 minutes)"
-  option :lines, type: :numeric, aliases: "-n", desc: "Number of lines to show from each server"
-  option :grep, aliases: "-g", desc: "Show lines with grep match only (use this to fetch specific requests by id)"
-  option :follow, aliases: "-f", desc: "Follow log on primary server (or specific host set by --hosts)"
-  def logs
-    # FIXME: Catch when app containers aren't running
-
-    grep = options[:grep]
-
-    if options[:follow]
-      run_locally do
-        info "Following logs on #{MRSK.primary_host}..."
-
-        MRSK.specific_roles ||= ["web"]
-        role = MRSK.roles_on(MRSK.primary_host).first
-
-        info MRSK.app(role: role).follow_logs(host: MRSK.primary_host, grep: grep)
-        exec MRSK.app(role: role).follow_logs(host: MRSK.primary_host, grep: grep)
-      end
-    else
-      since = options[:since]
-      lines = options[:lines].presence || ((since || grep) ? nil : 100) # Default to 100 lines if since or grep isn't set
-
-      on(MRSK.hosts) do |host|
-        roles = MRSK.roles_on(host)
-
-        roles.each do |role|
-          begin
-            puts_by_host host, capture_with_info(*MRSK.app(role: role).logs(since: since, lines: lines, grep: grep))
-          rescue SSHKit::Command::Failed
-            puts_by_host host, "Nothing found"
-          end
-        end
-      end
-    end
-  end
-
-  desc "remove", "Remove app containers and images from servers"
-  def remove
-    mutating do
-      stop
-      remove_containers
-      remove_images
-    end
-  end
-
-  desc "remove_container [VERSION]", "Remove app container with given version from servers", hide: true
-  def remove_container(version)
-    mutating do
-      on(MRSK.hosts) do |host|
-        roles = MRSK.roles_on(host)
-
-        roles.each do |role|
-          execute *MRSK.auditor.record("Removed app container with version #{version}", role: role), verbosity: :debug
-          execute *MRSK.app(role: role).remove_container(version: version)
-        end
-      end
-    end
-  end
-
-  desc "remove_containers", "Remove all app containers from servers", hide: true
-  def remove_containers
-    mutating do
-      on(MRSK.hosts) do |host|
-        roles = MRSK.roles_on(host)
-
-        roles.each do |role|
-          execute *MRSK.auditor.record("Removed all app containers", role: role), verbosity: :debug
-          execute *MRSK.app(role: role).remove_containers
-        end
-      end
-    end
-  end
-
-  desc "remove_images", "Remove all app images from servers", hide: true
-  def remove_images
-    mutating do
-      on(MRSK.hosts) do
-        execute *MRSK.auditor.record("Removed all app images"), verbosity: :debug
-        execute *MRSK.app.remove_images
-      end
-    end
-  end
-
-  desc "version", "Show app version currently running on servers"
-  def version
-    on(MRSK.hosts) { |host| puts_by_host host, capture_with_info(*MRSK.app.current_running_version).strip }
-  end
-
-  private
-    def using_version(new_version)
-      if new_version
-        begin
-          old_version = MRSK.config.version
-          MRSK.config.version = new_version
-          yield new_version
-        ensure
-          MRSK.config.version = old_version
-        end
-      else
-        yield MRSK.config.version
-      end
-    end
-
-    def current_running_version(host: MRSK.primary_host)
-      version = nil
-      on(host) { version = capture_with_info(*MRSK.app.current_running_version).strip }
-      version.presence
-    end
-
-    def stale_versions(host:, role:)
-      versions = nil
-      on(host) do
-        versions = \
-          capture_with_info(*MRSK.app(role: role).list_versions, raise_on_non_zero_exit: false)
-          .split("\n")
-          .drop(1)
-      end
-      versions
-    end
-
-    def version_or_latest
-      options[:version] || "latest"
-    end
-end

lib/mrsk/cli/build.rb

@@ -1,100 +0,0 @@
-class Mrsk::Cli::Build < Mrsk::Cli::Base
-  class BuildError < StandardError; end
-
-  desc "deliver", "Build app and push app image to registry then pull image on servers"
-  def deliver
-    mutating do
-      push
-      pull
-    end
-  end
-
-  desc "push", "Build and push app image to registry"
-  def push
-    mutating do
-      cli = self
-
-      verify_local_dependencies
-      run_hook "pre-build"
-
-      run_locally do
-        begin
-          MRSK.with_verbosity(:debug) { execute *MRSK.builder.push }
-        rescue SSHKit::Command::Failed => e
-          if e.message =~ /(no builder)|(no such file or directory)/
-            error "Missing compatible builder, so creating a new one first"
-
-            if cli.create
-              MRSK.with_verbosity(:debug) { execute *MRSK.builder.push }
-            end
-          else
-            raise
-          end
-        end
-      end
-    end
-  end
-
-  desc "pull", "Pull app image from registry onto servers"
-  def pull
-    mutating do
-      on(MRSK.hosts) do
-        execute *MRSK.auditor.record("Pulled image with version #{MRSK.config.version}"), verbosity: :debug
-        execute *MRSK.builder.clean, raise_on_non_zero_exit: false
-        execute *MRSK.builder.pull
-      end
-    end
-  end
-
-  desc "create", "Create a build setup"
-  def create
-    mutating do
-      run_locally do
-        begin
-          debug "Using builder: #{MRSK.builder.name}"
-          execute *MRSK.builder.create
-        rescue SSHKit::Command::Failed => e
-          if e.message =~ /stderr=(.*)/
-            error "Couldn't create remote builder: #{$1}"
-            false
-          else
-            raise
-          end
-        end
-      end
-    end
-  end
-
-  desc "remove", "Remove build setup"
-  def remove
-    mutating do
-      run_locally do
-        debug "Using builder: #{MRSK.builder.name}"
-        execute *MRSK.builder.remove
-      end
-    end
-  end
-
-  desc "details", "Show build setup"
-  def details
-    run_locally do
-      puts "Builder: #{MRSK.builder.name}"
-      puts capture(*MRSK.builder.info)
-    end
-  end
-
-  private
-    def verify_local_dependencies
-      run_locally do
-        begin
-          execute *MRSK.builder.ensure_local_dependencies_installed
-        rescue SSHKit::Command::Failed => e
-          build_error = e.message =~ /command not found/ ?
-            "Docker is not installed locally" :
-            "Docker buildx plugin is not installed locally"
-
-          raise BuildError, build_error
-        end
-      end
-    end
-end

lib/mrsk/cli/healthcheck.rb

@@ -1,20 +0,0 @@
-class Mrsk::Cli::Healthcheck < Mrsk::Cli::Base
-  default_command :perform
-
-  desc "perform", "Health check current app version"
-  def perform
-    on(MRSK.primary_host) do
-      begin
-        execute *MRSK.healthcheck.run
-        Mrsk::Utils::HealthcheckPoller.wait_for_healthy { capture_with_info(*MRSK.healthcheck.status) }
-      rescue Mrsk::Utils::HealthcheckPoller::HealthcheckError => e
-        error capture_with_info(*MRSK.healthcheck.logs)
-        error capture_with_pretty_json(*MRSK.healthcheck.container_health_log)
-        raise
-      ensure
-        execute *MRSK.healthcheck.stop, raise_on_non_zero_exit: false
-        execute *MRSK.healthcheck.remove, raise_on_non_zero_exit: false
-      end
-    end
-  end
-end

lib/mrsk/cli/main.rb

@@ -1,249 +0,0 @@
-class Mrsk::Cli::Main < Mrsk::Cli::Base
-  desc "setup", "Setup all accessories and deploy app to servers"
-  def setup
-    print_runtime do
-      mutating do
-        invoke "mrsk:cli:server:bootstrap"
-        invoke "mrsk:cli:accessory:boot", [ "all" ]
-        deploy
-      end
-    end
-  end
-
-  desc "deploy", "Deploy app to servers"
-  option :skip_push, aliases: "-P", type: :boolean, default: false, desc: "Skip image build and push"
-  def deploy
-    runtime = print_runtime do
-      mutating do
-        invoke_options = deploy_options
-
-        say "Log into image registry...", :magenta
-        invoke "mrsk:cli:registry:login", [], invoke_options
-
-        if options[:skip_push]
-          say "Pull app image...", :magenta
-          invoke "mrsk:cli:build:pull", [], invoke_options
-        else
-          say "Build and push app image...", :magenta
-          invoke "mrsk:cli:build:deliver", [], invoke_options
-        end
-
-        run_hook "pre-deploy"
-
-        say "Ensure Traefik is running...", :magenta
-        invoke "mrsk:cli:traefik:boot", [], invoke_options
-
-        say "Ensure app can pass healthcheck...", :magenta
-        invoke "mrsk:cli:healthcheck:perform", [], invoke_options
-
-        say "Detect stale containers...", :magenta
-        invoke "mrsk:cli:app:stale_containers", [], invoke_options
-
-        invoke "mrsk:cli:app:boot", [], invoke_options
-
-        say "Prune old containers and images...", :magenta
-        invoke "mrsk:cli:prune:all", [], invoke_options
-      end
-    end
-
-    run_hook "post-deploy", runtime: runtime.round
-  end
-
-  desc "redeploy", "Deploy app to servers without bootstrapping servers, starting Traefik, pruning, and registry login"
-  option :skip_push, aliases: "-P", type: :boolean, default: false, desc: "Skip image build and push"
-  def redeploy
-    runtime = print_runtime do
-      mutating do
-        invoke_options = deploy_options
-
-        if options[:skip_push]
-          say "Pull app image...", :magenta
-          invoke "mrsk:cli:build:pull", [], invoke_options
-        else
-          say "Build and push app image...", :magenta
-          invoke "mrsk:cli:build:deliver", [], invoke_options
-        end
-
-        run_hook "pre-deploy"
-
-        say "Ensure app can pass healthcheck...", :magenta
-        invoke "mrsk:cli:healthcheck:perform", [], invoke_options
-
-        say "Detect stale containers...", :magenta
-        invoke "mrsk:cli:app:stale_containers", [], invoke_options
-
-        invoke "mrsk:cli:app:boot", [], invoke_options
-      end
-    end
-
-    run_hook "post-deploy", runtime: runtime.round
-  end
-
-  desc "rollback [VERSION]", "Rollback app to VERSION"
-  def rollback(version)
-    rolled_back = false
-    runtime = print_runtime do
-      mutating do
-        invoke_options = deploy_options
-
-        MRSK.config.version = version
-        old_version = nil
-
-        if container_available?(version)
-          run_hook "pre-deploy"
-
-          invoke "mrsk:cli:app:boot", [], invoke_options.merge(version: version)
-          rolled_back = true
-        else
-          say "The app version '#{version}' is not available as a container (use 'mrsk app containers' for available versions)", :red
-        end
-      end
-    end
-
-    run_hook "post-deploy", runtime: runtime.round if rolled_back
-  end
-
-  desc "details", "Show details about all containers"
-  def details
-    invoke "mrsk:cli:traefik:details"
-    invoke "mrsk:cli:app:details"
-    invoke "mrsk:cli:accessory:details", [ "all" ]
-  end
-
-  desc "audit", "Show audit log from servers"
-  def audit
-    on(MRSK.hosts) do |host|
-      puts_by_host host, capture_with_info(*MRSK.auditor.reveal)
-    end
-  end
-
-  desc "config", "Show combined config (including secrets!)"
-  def config
-    run_locally do
-      puts Mrsk::Utils.redacted(MRSK.config.to_h).to_yaml
-    end
-  end
-
-  desc "init", "Create config stub in config/deploy.yml and env stub in .env"
-  option :bundle, type: :boolean, default: false, desc: "Add MRSK to the Gemfile and create a bin/mrsk binstub"
-  def init
-    require "fileutils"
-
-    if (deploy_file = Pathname.new(File.expand_path("config/deploy.yml"))).exist?
-      puts "Config file already exists in config/deploy.yml (remove first to create a new one)"
-    else
-      FileUtils.mkdir_p deploy_file.dirname
-      FileUtils.cp_r Pathname.new(File.expand_path("templates/deploy.yml", __dir__)), deploy_file
-      puts "Created configuration file in config/deploy.yml"
-    end
-
-    unless (deploy_file = Pathname.new(File.expand_path(".env"))).exist?
-      FileUtils.cp_r Pathname.new(File.expand_path("templates/template.env", __dir__)), deploy_file
-      puts "Created .env file"
-    end
-
-    unless (hooks_dir = Pathname.new(File.expand_path(".mrsk/hooks"))).exist?
-      hooks_dir.mkpath
-      Pathname.new(File.expand_path("templates/sample_hooks", __dir__)).each_child do |sample_hook|
-        FileUtils.cp sample_hook, hooks_dir, preserve: true
-      end
-      puts "Created sample hooks in .mrsk/hooks"
-    end
-
-    if options[:bundle]
-      if (binstub = Pathname.new(File.expand_path("bin/mrsk"))).exist?
-        puts "Binstub already exists in bin/mrsk (remove first to create a new one)"
-      else
-        puts "Adding MRSK to Gemfile and bundle..."
-        run_locally do
-          execute :bundle, :add, :mrsk
-          execute :bundle, :binstubs, :mrsk
-        end
-        puts "Created binstub file in bin/mrsk"
-      end
-    end
-  end
-
-  desc "envify", "Create .env by evaluating .env.erb (or .env.staging.erb -> .env.staging when using -d staging)"
-  def envify
-    if destination = options[:destination]
-      env_template_path = ".env.#{destination}.erb"
-      env_path          = ".env.#{destination}"
-    else
-      env_template_path = ".env.erb"
-      env_path          = ".env"
-    end
-
-    File.write(env_path, ERB.new(File.read(env_template_path)).result, perm: 0600)
-  end
-
-  desc "remove", "Remove Traefik, app, accessories, and registry session from servers"
-  option :confirmed, aliases: "-y", type: :boolean, default: false, desc: "Proceed without confirmation question"
-  def remove
-    mutating do
-      if options[:confirmed] || ask("This will remove all containers and images. Are you sure?", limited_to: %w( y N ), default: "N") == "y"
-        invoke "mrsk:cli:traefik:remove", [], options.without(:confirmed)
-        invoke "mrsk:cli:app:remove", [], options.without(:confirmed)
-        invoke "mrsk:cli:accessory:remove", [ "all" ], options
-        invoke "mrsk:cli:registry:logout", [], options.without(:confirmed)
-      end
-    end
-  end
-
-  desc "version", "Show MRSK version"
-  def version
-    puts Mrsk::VERSION
-  end
-
-  desc "accessory", "Manage accessories (db/redis/search)"
-  subcommand "accessory", Mrsk::Cli::Accessory
-
-  desc "app", "Manage application"
-  subcommand "app", Mrsk::Cli::App
-
-  desc "build", "Build application image"
-  subcommand "build", Mrsk::Cli::Build
-
-  desc "healthcheck", "Healthcheck application"
-  subcommand "healthcheck", Mrsk::Cli::Healthcheck
-
-  desc "lock", "Manage the deploy lock"
-  subcommand "lock", Mrsk::Cli::Lock
-
-  desc "prune", "Prune old application images and containers"
-  subcommand "prune", Mrsk::Cli::Prune
-
-  desc "registry", "Login and -out of the image registry"
-  subcommand "registry", Mrsk::Cli::Registry
-
-  desc "server", "Bootstrap servers with curl and Docker"
-  subcommand "server", Mrsk::Cli::Server
-
-  desc "traefik", "Manage Traefik load balancer"
-  subcommand "traefik", Mrsk::Cli::Traefik
-
-  private
-    def container_available?(version)
-      begin
-        on(MRSK.hosts) do
-          MRSK.roles_on(host).each do |role|
-            container_id = capture_with_info(*MRSK.app(role: role).container_id_for_version(version))
-            raise "Container not found" unless container_id.present?
-          end
-        end
-      rescue SSHKit::Runner::ExecuteError => e
-        if e.message =~ /Container not found/
-          say "Error looking for container version #{version}: #{e.message}"
-          return false
-        else
-          raise
-        end
-      end
-
-      true
-    end
-
-    def deploy_options
-      { "version" => MRSK.config.version }.merge(options.without("skip_push"))
-    end
-end

lib/mrsk/cli/prune.rb

@@ -1,30 +0,0 @@
-class Mrsk::Cli::Prune < Mrsk::Cli::Base
-  desc "all", "Prune unused images and stopped containers"
-  def all
-    mutating do
-      containers
-      images
-    end
-  end
-
-  desc "images", "Prune dangling images"
-  def images
-    mutating do
-      on(MRSK.hosts) do
-        execute *MRSK.auditor.record("Pruned images"), verbosity: :debug
-        execute *MRSK.prune.dangling_images
-        execute *MRSK.prune.tagged_images
-      end
-    end
-  end
-
-  desc "containers", "Prune all stopped containers, except the last 5"
-  def containers
-    mutating do
-      on(MRSK.hosts) do
-        execute *MRSK.auditor.record("Pruned containers"), verbosity: :debug
-        execute *MRSK.prune.containers
-      end
-    end
-  end
-end

lib/mrsk/cli/server.rb

@@ -1,21 +0,0 @@
-class Mrsk::Cli::Server < Mrsk::Cli::Base
-  desc "bootstrap", "Set up Docker to run MRSK apps"
-  def bootstrap
-    missing = []
-
-    on(MRSK.hosts | MRSK.accessory_hosts) do |host|
-      unless execute(*MRSK.docker.installed?, raise_on_non_zero_exit: false)
-        if execute(*MRSK.docker.superuser?, raise_on_non_zero_exit: false)
-          info "Missing Docker on #{host}. Installing…"
-          execute *MRSK.docker.install
-        else
-          missing << host
-        end
-      end
-    end
-
-    if missing.any?
-      raise "Docker is not installed on #{missing.join(", ")} and can't be automatically installed without having root access and the `curl` command available. Install Docker manually: https://docs.docker.com/engine/install/"
-    end
-  end
-end

lib/mrsk/cli/templates/sample_hooks/post-deploy.sample

@@ -1,14 +0,0 @@
-#!/bin/sh
-
-# A sample post-deploy hook
-#
-# These environment variables are available:
-# MRSK_RECORDED_AT
-# MRSK_PERFORMER
-# MRSK_VERSION
-# MRSK_HOSTS
-# MRSK_ROLE (if set)
-# MRSK_DESTINATION (if set)
-# MRSK_RUNTIME
-
-echo "$MRSK_PERFORMER deployed $MRSK_VERSION to $MRSK_DESTINATION in $MRSK_RUNTIME seconds"

lib/mrsk/cli/templates/template.env

@@ -1,2 +0,0 @@
-MRSK_REGISTRY_PASSWORD=change-this
-RAILS_MASTER_KEY=another-env

lib/mrsk/cli/traefik.rb

@@ -1,111 +0,0 @@
-class Mrsk::Cli::Traefik < Mrsk::Cli::Base
-  desc "boot", "Boot Traefik on servers"
-  def boot
-    mutating do
-      on(MRSK.traefik_hosts) do
-        execute *MRSK.registry.login
-        execute *MRSK.traefik.run, raise_on_non_zero_exit: false
-      end
-    end
-  end
-
-  desc "reboot", "Reboot Traefik on servers (stop container, remove container, start new container)"
-  option :rolling, type: :boolean, default: false, desc: "Reboot traefik on hosts in sequence, rather than in parallel"
-  def reboot
-    mutating do
-      on(MRSK.traefik_hosts, in: options[:rolling] ? :sequence : :parallel) do
-        execute *MRSK.auditor.record("Rebooted traefik"), verbosity: :debug
-        execute *MRSK.registry.login
-        execute *MRSK.traefik.stop, raise_on_non_zero_exit: false
-        execute *MRSK.traefik.remove_container
-        execute *MRSK.traefik.run, raise_on_non_zero_exit: false
-      end
-    end
-  end
-
-  desc "start", "Start existing Traefik container on servers"
-  def start
-    mutating do
-      on(MRSK.traefik_hosts) do
-        execute *MRSK.auditor.record("Started traefik"), verbosity: :debug
-        execute *MRSK.traefik.start, raise_on_non_zero_exit: false
-      end
-    end
-  end
-
-  desc "stop", "Stop existing Traefik container on servers"
-  def stop
-    mutating do
-      on(MRSK.traefik_hosts) do
-        execute *MRSK.auditor.record("Stopped traefik"), verbosity: :debug
-        execute *MRSK.traefik.stop, raise_on_non_zero_exit: false
-      end
-    end
-  end
-
-  desc "restart", "Restart existing Traefik container on servers"
-  def restart
-    mutating do
-      stop
-      start
-    end
-  end
-
-  desc "details", "Show details about Traefik container from servers"
-  def details
-    on(MRSK.traefik_hosts) { |host| puts_by_host host, capture_with_info(*MRSK.traefik.info), type: "Traefik" }
-  end
-
-  desc "logs", "Show log lines from Traefik on servers"
-  option :since, aliases: "-s", desc: "Show logs since timestamp (e.g. 2013-01-02T13:23:37Z) or relative (e.g. 42m for 42 minutes)"
-  option :lines, type: :numeric, aliases: "-n", desc: "Number of log lines to pull from each server"
-  option :grep, aliases: "-g", desc: "Show lines with grep match only (use this to fetch specific requests by id)"
-  option :follow, aliases: "-f", desc: "Follow logs on primary server (or specific host set by --hosts)"
-  def logs
-    grep = options[:grep]
-
-    if options[:follow]
-      run_locally do
-        info "Following logs on #{MRSK.primary_host}..."
-        info MRSK.traefik.follow_logs(host: MRSK.primary_host, grep: grep)
-        exec MRSK.traefik.follow_logs(host: MRSK.primary_host, grep: grep)
-      end
-    else
-      since = options[:since]
-      lines = options[:lines].presence || ((since || grep) ? nil : 100) # Default to 100 lines if since or grep isn't set
-
-      on(MRSK.traefik_hosts) do |host|
-        puts_by_host host, capture(*MRSK.traefik.logs(since: since, lines: lines, grep: grep)), type: "Traefik"
-      end
-    end
-  end
-
-  desc "remove", "Remove Traefik container and image from servers"
-  def remove
-    mutating do
-      stop
-      remove_container
-      remove_image
-    end
-  end
-
-  desc "remove_container", "Remove Traefik container from servers", hide: true
-  def remove_container
-    mutating do
-      on(MRSK.traefik_hosts) do
-        execute *MRSK.auditor.record("Removed traefik container"), verbosity: :debug
-        execute *MRSK.traefik.remove_container
-      end
-    end
-  end
-
-  desc "remove_image", "Remove Traefik image from servers", hide: true
-  def remove_image
-    mutating do
-      on(MRSK.traefik_hosts) do
-        execute *MRSK.auditor.record("Removed traefik image"), verbosity: :debug
-        execute *MRSK.traefik.remove_image
-      end
-    end
-  end
-end

lib/mrsk/commander.rb

@@ -1,150 +0,0 @@
-require "active_support/core_ext/enumerable"
-require "active_support/core_ext/module/delegation"
-
-class Mrsk::Commander
-  attr_accessor :verbosity, :holding_lock, :hold_lock_on_error
-
-  def initialize
-    self.verbosity = :info
-    self.holding_lock = false
-    self.hold_lock_on_error = false
-  end
-
-  def config
-    @config ||= Mrsk::Configuration.create_from(**@config_kwargs).tap do |config|
-      @config_kwargs = nil
-      configure_sshkit_with(config)
-    end
-  end
-
-  def configure(**kwargs)
-    @config, @config_kwargs = nil, kwargs
-  end
-
-  attr_reader :specific_roles, :specific_hosts
-
-  def specific_primary!
-    self.specific_hosts = [ config.primary_web_host ]
-  end
-
-  def specific_roles=(role_names)
-    @specific_roles = config.roles.select { |r| role_names.include?(r.name) } if role_names.present?
-  end
-
-  def specific_hosts=(hosts)
-    @specific_hosts = config.all_hosts & hosts if hosts.present?
-  end
-
-  def primary_host
-    specific_hosts&.first || specific_roles&.first&.primary_host || config.primary_web_host
-  end
-
-  def roles
-    (specific_roles || config.roles).select do |role|
-      ((specific_hosts || config.all_hosts) & role.hosts).any?
-    end
-  end
-
-  def hosts
-    (specific_hosts || config.all_hosts).select do |host|
-      (specific_roles || config.roles).flat_map(&:hosts).include?(host)
-    end
-  end
-
-  def boot_strategy
-    if config.boot.limit.present?
-      { in: :groups, limit: config.boot.limit, wait: config.boot.wait }
-    else
-      {}
-    end
-  end
-
-  def roles_on(host)
-    roles.select { |role| role.hosts.include?(host.to_s) }.map(&:name)
-  end
-
-  def traefik_hosts
-    specific_hosts || config.traefik_hosts
-  end
-
-  def accessory_hosts
-    specific_hosts || config.accessories.flat_map(&:hosts)
-  end
-
-  def accessory_names
-    config.accessories&.collect(&:name) || []
-  end
-
-
-  def app(role: nil)
-    Mrsk::Commands::App.new(config, role: role)
-  end
-
-  def accessory(name)
-    Mrsk::Commands::Accessory.new(config, name: name)
-  end
-
-  def auditor(**details)
-    Mrsk::Commands::Auditor.new(config, **details)
-  end
-
-  def builder
-    @builder ||= Mrsk::Commands::Builder.new(config)
-  end
-
-  def docker
-    @docker ||= Mrsk::Commands::Docker.new(config)
-  end
-
-  def healthcheck
-    @healthcheck ||= Mrsk::Commands::Healthcheck.new(config)
-  end
-
-  def hook
-    @hook ||= Mrsk::Commands::Hook.new(config)
-  end
-
-  def lock
-    @lock ||= Mrsk::Commands::Lock.new(config)
-  end
-
-  def prune
-    @prune ||= Mrsk::Commands::Prune.new(config)
-  end
-
-  def registry
-    @registry ||= Mrsk::Commands::Registry.new(config)
-  end
-
-  def traefik
-    @traefik ||= Mrsk::Commands::Traefik.new(config)
-  end
-
-  def with_verbosity(level)
-    old_level = self.verbosity
-
-    self.verbosity = level
-    SSHKit.config.output_verbosity = level
-
-    yield
-  ensure
-    self.verbosity = old_level
-    SSHKit.config.output_verbosity = old_level
-  end
-
-  def holding_lock?
-    self.holding_lock
-  end
-
-  def hold_lock_on_error?
-    self.hold_lock_on_error
-  end
-
-  private
-    # Lazy setup of SSHKit
-    def configure_sshkit_with(config)
-      SSHKit::Backend::Netssh.configure { |ssh| ssh.ssh_options = config.ssh_options }
-      SSHKit.config.command_map[:docker] = "docker" # No need to use /usr/bin/env, just clogs up the logs
-      SSHKit.config.output_verbosity = verbosity
-    end
-end

lib/mrsk/commands.rb

@@ -1,2 +0,0 @@
-module Mrsk::Commands
-end

lib/mrsk/commands/app.rb

@@ -1,169 +0,0 @@
-class Mrsk::Commands::App < Mrsk::Commands::Base
-  ACTIVE_DOCKER_STATUSES = [ :running, :restarting ]
-
-  attr_reader :role
-
-  def initialize(config, role: nil)
-    super(config)
-    @role = role
-  end
-
-  def start_or_run(hostname: nil)
-    combine start, run(hostname: hostname), by: "||"
-  end
-
-  def run(hostname: nil)
-    role = config.role(self.role)
-
-    docker :run,
-      "--detach",
-      "--restart unless-stopped",
-      "--name", container_name,
-      *(["--hostname", hostname] if hostname),
-      "-e", "MRSK_CONTAINER_NAME=\"#{container_name}\"",
-      *role.env_args,
-      *role.health_check_args,
-      *config.logging_args,
-      *config.volume_args,
-      *role.label_args,
-      *role.option_args,
-      config.absolute_image,
-      role.cmd
-  end
-
-  def start
-    docker :start, container_name
-  end
-
-  def status(version:)
-    pipe container_id_for_version(version), xargs(docker(:inspect, "--format", DOCKER_HEALTH_STATUS_FORMAT))
-  end
-
-  def stop(version: nil)
-    pipe \
-      version ? container_id_for_version(version) : current_running_container_id,
-      xargs(config.stop_wait_time ? docker(:stop, "-t", config.stop_wait_time) : docker(:stop))
-  end
-
-  def info
-    docker :ps, *filter_args
-  end
-
-
-  def logs(since: nil, lines: nil, grep: nil)
-    pipe \
-      current_running_container_id,
-      "xargs docker logs#{" --since #{since}" if since}#{" --tail #{lines}" if lines} 2>&1",
-      ("grep '#{grep}'" if grep)
-  end
-
-  def follow_logs(host:, grep: nil)
-    run_over_ssh \
-      pipe(
-        current_running_container_id,
-        "xargs docker logs --timestamps --tail 10 --follow 2>&1",
-        (%(grep "#{grep}") if grep)
-      ),
-      host: host
-  end
-
-
-  def execute_in_existing_container(*command, interactive: false)
-    docker :exec,
-      ("-it" if interactive),
-      container_name,
-      *command
-  end
-
-  def execute_in_new_container(*command, interactive: false)
-    docker :run,
-      ("-it" if interactive),
-      "--rm",
-      *config.env_args,
-      *config.volume_args,
-      config.absolute_image,
-      *command
-  end
-
-  def execute_in_existing_container_over_ssh(*command, host:)
-    run_over_ssh execute_in_existing_container(*command, interactive: true), host: host
-  end
-
-  def execute_in_new_container_over_ssh(*command, host:)
-    run_over_ssh execute_in_new_container(*command, interactive: true), host: host
-  end
-
-
-  def current_running_container_id
-    docker :ps, "--quiet", *filter_args(statuses: ACTIVE_DOCKER_STATUSES), "--latest"
-  end
-
-  def container_id_for_version(version, only_running: false)
-    container_id_for(container_name: container_name(version), only_running: only_running)
-  end
-
-  def current_running_version
-    list_versions("--latest", statuses: ACTIVE_DOCKER_STATUSES)
-  end
-
-  def list_versions(*docker_args, statuses: nil)
-    pipe \
-      docker(:ps, *filter_args(statuses: statuses), *docker_args, "--format", '"{{.Names}}"'),
-      %(grep -oE "\\-[^-]+$"), # Extract SHA from "service-role-dest-SHA"
-      %(cut -c 2-)
-  end
-
-  def list_containers
-    docker :container, :ls, "--all", *filter_args
-  end
-
-  def list_container_names
-    [ *list_containers, "--format", "'{{ .Names }}'" ]
-  end
-
-  def remove_container(version:)
-    pipe \
-      container_id_for(container_name: container_name(version)),
-      xargs(docker(:container, :rm))
-  end
-
-  def rename_container(version:, new_version:)
-    docker :rename, container_name(version), container_name(new_version)
-  end
-
-  def remove_containers
-    docker :container, :prune, "--force", *filter_args
-  end
-
-  def list_images
-    docker :image, :ls, config.repository
-  end
-
-  def remove_images
-    docker :image, :prune, "--all", "--force", *filter_args
-  end
-
-  def tag_current_as_latest
-    docker :tag, config.absolute_image, config.latest_image
-  end
-
-
-  private
-    def container_name(version = nil)
-      [ config.service, role, config.destination, version || config.version ].compact.join("-")
-    end
-
-    def filter_args(statuses: nil)
-      argumentize "--filter", filters(statuses: statuses)
-    end
-
-    def filters(statuses: nil)
-      [ "label=service=#{config.service}" ].tap do |filters|
-        filters << "label=destination=#{config.destination}" if config.destination
-        filters << "label=role=#{role}" if role
-        statuses&.each do |status|
-          filters << "status=#{status}"
-        end
-      end
-    end
-end

lib/mrsk/commands/builder.rb

@@ -1,62 +0,0 @@
-class Mrsk::Commands::Builder < Mrsk::Commands::Base
-  delegate :create, :remove, :push, :clean, :pull, :info, to: :target
-
-  def name
-    target.class.to_s.remove("Mrsk::Commands::Builder::").underscore.inquiry
-  end
-
-  def target
-    case
-    when !config.builder.multiarch? && !config.builder.cached?
-      native
-    when !config.builder.multiarch? && config.builder.cached?
-      native_cached
-    when config.builder.local? && config.builder.remote?
-      multiarch_remote
-    when config.builder.remote?
-      native_remote
-    else
-      multiarch
-    end
-  end
-
-  def native
-    @native ||= Mrsk::Commands::Builder::Native.new(config)
-  end
-
-  def native_cached
-    @native ||= Mrsk::Commands::Builder::Native::Cached.new(config)
-  end
-
-  def native_remote
-    @native ||= Mrsk::Commands::Builder::Native::Remote.new(config)
-  end
-
-  def multiarch
-    @multiarch ||= Mrsk::Commands::Builder::Multiarch.new(config)
-  end
-
-  def multiarch_remote
-    @multiarch_remote ||= Mrsk::Commands::Builder::Multiarch::Remote.new(config)
-  end
-
-
-  def ensure_local_dependencies_installed
-    if name.native?
-      ensure_local_docker_installed
-    else
-      combine \
-        ensure_local_docker_installed,
-        ensure_local_buildx_installed
-    end
-  end
-
-  private
-    def ensure_local_docker_installed
-      docker "--version"
-    end
-
-    def ensure_local_buildx_installed
-      docker :buildx, "version"
-    end
-end

lib/mrsk/commands/healthcheck.rb

@@ -1,57 +0,0 @@
-class Mrsk::Commands::Healthcheck < Mrsk::Commands::Base
-  EXPOSED_PORT = 3999
-
-  def run
-    web = config.role(:web)
-
-    docker :run,
-      "--detach",
-      "--name", container_name_with_version,
-      "--publish", "#{EXPOSED_PORT}:#{config.healthcheck["port"]}",
-      "--label", "service=#{container_name}",
-      "-e", "MRSK_CONTAINER_NAME=\"#{container_name}\"",
-      *web.env_args,
-      *web.health_check_args,
-      *config.volume_args,
-      *web.option_args,
-      config.absolute_image,
-      web.cmd
-  end
-
-  def status
-    pipe container_id, xargs(docker(:inspect, "--format", DOCKER_HEALTH_STATUS_FORMAT))
-  end
-
-  def container_health_log
-    pipe container_id, xargs(docker(:inspect, "--format", DOCKER_HEALTH_LOG_FORMAT))
-  end
-
-  def logs
-    pipe container_id, xargs(docker(:logs, "--tail", 50, "2>&1"))
-  end
-
-  def stop
-    pipe container_id, xargs(docker(:stop))
-  end
-
-  def remove
-    pipe container_id, xargs(docker(:container, :rm))
-  end
-
-  private
-    def container_name
-      [ "healthcheck", config.service, config.destination ].compact.join("-")
-    end
-
-    def container_name_with_version
-      "#{container_name}-#{config.version}"
-    end
-
-    def container_id
-      container_id_for(container_name: container_name_with_version)
-    end
-
-    def health_url
-      "http://localhost:#{EXPOSED_PORT}#{config.healthcheck["path"]}"
-    end
-end

lib/mrsk/commands/traefik.rb

@@ -1,100 +0,0 @@
-class Mrsk::Commands::Traefik < Mrsk::Commands::Base
-  delegate :argumentize, :argumentize_env_with_secrets, :optionize, to: Mrsk::Utils
-
-  DEFAULT_IMAGE = "traefik:v2.9"
-  CONTAINER_PORT = 80
-  DEFAULT_ARGS = {
-    'log.level' => 'DEBUG'
-  }
-
-  def run
-    docker :run, "--name traefik",
-      "--detach",
-      "--restart", "unless-stopped",
-      "--publish", port,
-      "--volume", "/var/run/docker.sock:/var/run/docker.sock",
-      *env_args,
-      *config.logging_args,
-      *label_args,
-      *docker_options_args,
-      image,
-      "--providers.docker",
-      *cmd_option_args
-  end
-
-  def start
-    docker :container, :start, "traefik"
-  end
-
-  def stop
-    docker :container, :stop, "traefik"
-  end
-
-  def info
-    docker :ps, "--filter", "name=^traefik$"
-  end
-
-  def logs(since: nil, lines: nil, grep: nil)
-    pipe \
-      docker(:logs, "traefik", (" --since #{since}" if since), (" --tail #{lines}" if lines), "--timestamps", "2>&1"),
-      ("grep '#{grep}'" if grep)
-  end
-
-  def follow_logs(host:, grep: nil)
-    run_over_ssh pipe(
-      docker(:logs, "traefik", "--timestamps", "--tail", "10", "--follow", "2>&1"),
-      (%(grep "#{grep}") if grep)
-    ).join(" "), host: host
-  end
-
-  def remove_container
-    docker :container, :prune, "--force", "--filter", "label=org.opencontainers.image.title=Traefik"
-  end
-
-  def remove_image
-    docker :image, :prune, "--all", "--force", "--filter", "label=org.opencontainers.image.title=Traefik"
-  end
-
-  def port
-    "#{host_port}:#{CONTAINER_PORT}"
-  end
-
-  private
-    def label_args
-      argumentize "--label", labels
-    end
-
-    def env_args
-      env_config = config.traefik["env"] || {}
-
-      if env_config.present?
-        argumentize_env_with_secrets(env_config)
-      else
-        []
-      end
-    end
-
-    def labels
-      config.traefik["labels"] || []
-    end
-
-    def image
-      config.traefik.fetch("image") { DEFAULT_IMAGE }
-    end
-
-    def docker_options_args
-      optionize(config.traefik["options"] || {})
-    end
-
-    def cmd_option_args
-      if args = config.traefik["args"]
-        optionize DEFAULT_ARGS.merge(args), with: "="
-      else
-        optionize DEFAULT_ARGS, with: "="
-      end
-    end
-
-    def host_port
-      config.traefik["host_port"] || CONTAINER_PORT
-    end
-end

lib/mrsk/configuration.rb

@@ -1,263 +0,0 @@
-require "active_support/ordered_options"
-require "active_support/core_ext/string/inquiry"
-require "active_support/core_ext/module/delegation"
-require "pathname"
-require "erb"
-require "net/ssh/proxy/jump"
-
-class Mrsk::Configuration
-  delegate :service, :image, :servers, :env, :labels, :registry, :stop_wait_time, :hooks_path, to: :raw_config, allow_nil: true
-  delegate :argumentize, :argumentize_env_with_secrets, :optionize, to: Mrsk::Utils
-
-  attr_accessor :destination
-  attr_accessor :raw_config
-
-  class << self
-    def create_from(config_file:, destination: nil, version: nil)
-      raw_config = load_config_files(config_file, *destination_config_file(config_file, destination))
-
-      new raw_config, destination: destination, version: version
-    end
-
-    private
-      def load_config_files(*files)
-        files.inject({}) { |config, file| config.deep_merge! load_config_file(file) }
-      end
-
-      def load_config_file(file)
-        if file.exist?
-          YAML.load(ERB.new(IO.read(file)).result).symbolize_keys
-        else
-          raise "Configuration file not found in #{file}"
-        end
-      end
-
-      def destination_config_file(base_config_file, destination)
-        base_config_file.sub_ext(".#{destination}.yml") if destination
-      end
-  end
-
-  def initialize(raw_config, destination: nil, version: nil, validate: true)
-    @raw_config = ActiveSupport::InheritableOptions.new(raw_config)
-    @destination = destination
-    @declared_version = version
-    valid? if validate
-  end
-
-
-  def version=(version)
-    @declared_version = version
-  end
-
-  def version
-    @declared_version.presence || ENV["VERSION"] || git_version
-  end
-
-  def abbreviated_version
-    Mrsk::Utils.abbreviate_version(version)
-  end
-
-
-  def roles
-    @roles ||= role_names.collect { |role_name| Role.new(role_name, config: self) }
-  end
-
-  def role(name)
-    roles.detect { |r| r.name == name.to_s }
-  end
-
-  def accessories
-    @accessories ||= raw_config.accessories&.keys&.collect { |name| Mrsk::Configuration::Accessory.new(name, config: self) } || []
-  end
-
-  def accessory(name)
-    accessories.detect { |a| a.name == name.to_s }
-  end
-
-
-  def all_hosts
-    roles.flat_map(&:hosts).uniq
-  end
-
-  def primary_web_host
-    role(:web).primary_host
-  end
-
-  def traefik_hosts
-    roles.select(&:running_traefik?).flat_map(&:hosts).uniq
-  end
-
-  def boot
-    Mrsk::Configuration::Boot.new(config: self)
-  end
-
-
-  def repository
-    [ raw_config.registry["server"], image ].compact.join("/")
-  end
-
-  def absolute_image
-    "#{repository}:#{version}"
-  end
-
-  def latest_image
-    "#{repository}:latest"
-  end
-
-  def service_with_version
-    "#{service}-#{version}"
-  end
-
-
-  def env_args
-    if raw_config.env.present?
-      argumentize_env_with_secrets(raw_config.env)
-    else
-      []
-    end
-  end
-
-  def volume_args
-    if raw_config.volumes.present?
-      argumentize "--volume", raw_config.volumes
-    else
-      []
-    end
-  end
-
-  def logging_args
-    if raw_config.logging.present?
-      optionize({ "log-driver" => raw_config.logging["driver"] }.compact) +
-        argumentize("--log-opt", raw_config.logging["options"])
-    else
-      argumentize("--log-opt", { "max-size" => "10m" })
-    end
-  end
-
-
-  def ssh_user
-    if raw_config.ssh.present?
-      raw_config.ssh["user"] || "root"
-    else
-      "root"
-    end
-  end
-
-  def ssh_proxy
-    if raw_config.ssh.present? && raw_config.ssh["proxy"]
-      Net::SSH::Proxy::Jump.new \
-        raw_config.ssh["proxy"].include?("@") ? raw_config.ssh["proxy"] : "root@#{raw_config.ssh["proxy"]}"
-    elsif raw_config.ssh.present? && raw_config.ssh["proxy_command"]
-      Net::SSH::Proxy::Command.new(raw_config.ssh["proxy_command"])
-    end
-  end
-
-  def ssh_options
-    { user: ssh_user, proxy: ssh_proxy, auth_methods: [ "publickey" ] }.compact
-  end
-
-
-  def healthcheck
-    { "path" => "/up", "port" => 3000, "max_attempts" => 7 }.merge(raw_config.healthcheck || {})
-  end
-
-  def readiness_delay
-    raw_config.readiness_delay || 7
-  end
-
-  def minimum_version
-    raw_config.minimum_version
-  end
-
-  def valid?
-    ensure_required_keys_present && ensure_valid_mrsk_version
-  end
-
-
-  def to_h
-    {
-      roles: role_names,
-      hosts: all_hosts,
-      primary_host: primary_web_host,
-      version: version,
-      repository: repository,
-      absolute_image: absolute_image,
-      service_with_version: service_with_version,
-      env_args: env_args,
-      volume_args: volume_args,
-      ssh_options: ssh_options,
-      builder: builder.to_h,
-      accessories: raw_config.accessories,
-      logging: logging_args,
-      healthcheck: healthcheck
-    }.compact
-  end
-
-  def traefik
-    raw_config.traefik || {}
-  end
-
-  def hooks_path
-    raw_config.hooks_path || ".mrsk/hooks"
-  end
-
-  def builder
-    Mrsk::Configuration::Builder.new(config: self)
-  end
-
-  # Will raise KeyError if any secret ENVs are missing
-  def ensure_env_available
-    env_args
-    roles.each(&:env_args)
-
-    true
-  end
-
-  private
-    # Will raise ArgumentError if any required config keys are missing
-    def ensure_required_keys_present
-      %i[ service image registry servers ].each do |key|
-        raise ArgumentError, "Missing required configuration for #{key}" unless raw_config[key].present?
-      end
-
-      if raw_config.registry["username"].blank?
-        raise ArgumentError, "You must specify a username for the registry in config/deploy.yml"
-      end
-
-      if raw_config.registry["password"].blank?
-        raise ArgumentError, "You must specify a password for the registry in config/deploy.yml (or set the ENV variable if that's used)"
-      end
-
-      roles.each do |role|
-        if role.hosts.empty?
-          raise ArgumentError, "No servers specified for the #{role.name} role"
-        end
-      end
-
-      true
-    end
-
-    def ensure_valid_mrsk_version
-      if minimum_version && Gem::Version.new(minimum_version) > Gem::Version.new(Mrsk::VERSION)
-        raise ArgumentError, "Current version is #{Mrsk::VERSION}, minimum required is #{minimum_version}"
-      end
-
-      true
-    end
-
-
-    def role_names
-      raw_config.servers.is_a?(Array) ? [ "web" ] : raw_config.servers.keys.sort
-    end
-
-    def git_version
-      @git_version ||=
-        if system("git rev-parse")
-          uncommitted_suffix = `git status --porcelain`.strip.present? ? "_uncommitted_#{SecureRandom.hex(8)}" : ""
-
-          "#{`git rev-parse HEAD`.strip}#{uncommitted_suffix}"
-        else
-          raise "Can't use commit hash as version, no git repository found in #{Dir.pwd}"
-        end
-    end
-end

lib/mrsk/configuration/role.rb

@@ -1,155 +0,0 @@
-class Mrsk::Configuration::Role
-  delegate :argumentize, :argumentize_env_with_secrets, :optionize, to: Mrsk::Utils
-
-  attr_accessor :name
-
-  def initialize(name, config:)
-   @name, @config = name.inquiry, config
-  end
-
-  def primary_host
-    hosts.first
-  end
-
-  def hosts
-    @hosts ||= extract_hosts_from_config
-  end
-
-  def labels
-    default_labels.merge(traefik_labels).merge(custom_labels)
-  end
-
-  def label_args
-    argumentize "--label", labels
-  end
-
-  def env
-    if config.env && config.env["secret"]
-      merged_env_with_secrets
-    else
-      merged_env
-    end
-  end
-
-  def env_args
-    argumentize_env_with_secrets env
-  end
-
-  def health_check_args
-    if health_check_cmd.present?
-      optionize({ "health-cmd" => health_check_cmd, "health-interval" => health_check_interval })
-    else
-      []
-    end
-  end
-
-  def health_check_cmd
-    options = specializations["healthcheck"] || {}
-    options = config.healthcheck.merge(options) if running_traefik?
-
-    options["cmd"] || http_health_check(port: options["port"], path: options["path"])
-  end
-
-  def health_check_interval
-    options = specializations["healthcheck"] || {}
-    options = config.healthcheck.merge(options) if running_traefik?
-
-    options["interval"] || "1s"
-  end
-
-  def cmd
-    specializations["cmd"]
-  end
-
-  def option_args
-    if args = specializations["options"]
-      optionize args
-    else
-      []
-    end
-  end
-
-  def running_traefik?
-    name.web? || specializations["traefik"]
-  end
-
-  private
-    attr_accessor :config
-
-    def extract_hosts_from_config
-      if config.servers.is_a?(Array)
-        config.servers
-      else
-        servers = config.servers[name]
-        servers.is_a?(Array) ? servers : Array(servers["hosts"])
-      end
-    end
-
-    def default_labels
-      if config.destination
-        { "service" => config.service, "role" => name, "destination" => config.destination }
-      else
-        { "service" => config.service, "role" => name }
-      end
-    end
-
-    def traefik_labels
-      if running_traefik?
-        {
-          # Setting a service property ensures that the generated service name will be consistent between versions
-          "traefik.http.services.#{traefik_service}.loadbalancer.server.scheme" => "http",
-
-          "traefik.http.routers.#{traefik_service}.rule" => "PathPrefix(`/`)",
-          "traefik.http.middlewares.#{traefik_service}-retry.retry.attempts" => "5",
-          "traefik.http.middlewares.#{traefik_service}-retry.retry.initialinterval" => "500ms",
-          "traefik.http.routers.#{traefik_service}.middlewares" => "#{traefik_service}-retry@docker"
-        }
-      else
-        {}
-      end
-    end
-
-    def traefik_service
-      [ config.service, name, config.destination ].compact.join("-")
-    end
-
-    def custom_labels
-      Hash.new.tap do |labels|
-        labels.merge!(config.labels) if config.labels.present?
-        labels.merge!(specializations["labels"]) if specializations["labels"].present?
-      end
-    end
-
-    def specializations
-      if config.servers.is_a?(Array) || config.servers[name].is_a?(Array)
-        { }
-      else
-        config.servers[name].except("hosts")
-      end
-    end
-
-    def specialized_env
-      specializations["env"] || {}
-    end
-
-    def merged_env
-      config.env&.merge(specialized_env) || {}
-    end
-
-    # Secrets are stored in an array, which won't merge by default, so have to do it by hand.
-    def merged_env_with_secrets
-      merged_env.tap do |new_env|
-        new_env["secret"] = Array(config.env["secret"]) + Array(specialized_env["secret"])
-
-        # If there's no secret/clear split, everything is clear
-        clear_app_env  = config.env["secret"] ? Array(config.env["clear"]) : Array(config.env["clear"] || config.env)
-        clear_role_env = specialized_env["secret"] ? Array(specialized_env["clear"]) : Array(specialized_env["clear"] || specialized_env)
-
-        new_env["clear"] = (clear_app_env + clear_role_env).uniq
-      end
-    end
-
-    def http_health_check(port:, path:)
-      "curl -f #{URI.join("http://localhost:#{port}", path)} || exit 1" if path.present? || port.present?
-    end
-end

lib/mrsk/sshkit_with_ext.rb

@@ -1,56 +0,0 @@
-require "sshkit"
-require "sshkit/dsl"
-require "active_support/core_ext/hash/deep_merge"
-require "json"
-
-class SSHKit::Backend::Abstract
-  def capture_with_info(*args, **kwargs)
-    capture(*args, **kwargs, verbosity: Logger::INFO)
-  end
-
-  def capture_with_debug(*args, **kwargs)
-    capture(*args, **kwargs, verbosity: Logger::DEBUG)
-  end
-
-  def capture_with_pretty_json(*args, **kwargs)
-    JSON.pretty_generate(JSON.parse(capture(*args, **kwargs)))
-  end
-
-  def puts_by_host(host, output, type: "App")
-    puts "#{type} Host: #{host}\n#{output}\n\n"
-  end
-
-  # Our execution pattern is for the CLI execute args lists returned
-  # from commands, but this doesn't support returning execution options
-  # from the command.
-  #
-  # Support this by using kwargs for CLI options and merging with the
-  # args-extracted options.
-  module CommandEnvMerge
-    private
-
-    # Override to merge options returned by commands in the args list with
-    # options passed by the CLI and pass them along as kwargs.
-    def command(args, options)
-      more_options, args = args.partition { |a| a.is_a? Hash }
-      more_options << options
-
-      build_command(args, **more_options.reduce(:deep_merge))
-    end
-
-    # Destructure options to pluck out env for merge
-    def build_command(args, env: nil, **options)
-      # Rely on native Ruby kwargs precedence rather than explicit Hash merges
-      SSHKit::Command.new(*args, **default_command_options, **options, env: env_for(env))
-    end
-
-    def default_command_options
-      { in: pwd_path, host: @host, user: @user, group: @group }
-    end
-
-    def env_for(env)
-      @env.to_h.merge(env.to_h)
-    end
-  end
-  prepend CommandEnvMerge
-end