diff --git a/lib/mrsk/commands/app.rb b/lib/mrsk/commands/app.rb
index a314a991..b072c862 100644
--- a/lib/mrsk/commands/app.rb
+++ b/lib/mrsk/commands/app.rb
@@ -15,8 +15,8 @@ class Mrsk::Commands::App < Mrsk::Commands::Base
       "--restart unless-stopped",
       "--name", config.service_with_version,
       "-e", redact("RAILS_MASTER_KEY=#{config.master_key}"),
-      config.envs,
-      config.labels,
+      *config.envs,
+      *config.labels,
       config.absolute_image
   end
 
diff --git a/lib/mrsk/configuration.rb b/lib/mrsk/configuration.rb
index 190d574b..015d38ee 100644
--- a/lib/mrsk/configuration.rb
+++ b/lib/mrsk/configuration.rb
@@ -73,6 +73,6 @@ class Mrsk::Configuration
     end
 
     def parameterize(param, hash)
-      hash.collect { |k, v| "#{param} #{k}=#{v}" }.join(" ")
+      hash.flat_map { |k, v| [ param, "#{k}=#{v}" ] }
     end
 end