diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 75dc2c0..d01a9a3 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -22,7 +22,7 @@ jobs:
     - name: Checkout
       uses: actions/checkout@v2
     - name: SPM tests
-      run: swift test --enable-code-coverage --sanitize=thread
+      run: swift test --enable-code-coverage
     - name: Convert coverage files
       run: |
         xcrun llvm-cov export -format "lcov" \
@@ -38,11 +38,9 @@ jobs:
     strategy:
       matrix:
         image:
-          - 'swift:5.4-bionic'
-          - 'swift:5.5-bionic'
-          - 'swift:5.5-focal'
-          - 'swift:5.5-amazonlinux2'
-          - 'swift:5.5-centos8'
+          - 'swift:5.4'
+          - 'swift:5.5'
+          - 'swift:5.6'
     
     container:
       image: ${{ matrix.image }}
@@ -51,7 +49,7 @@ jobs:
       uses: actions/checkout@v2
     - name: Test
       run: |
-        swift test --enable-test-discovery --enable-code-coverage
+        swift test --enable-code-coverage
     - name: Convert coverage files
       run: |
         llvm-cov export -format="lcov" \
diff --git a/.github/workflows/nightly.yml b/.github/workflows/nightly.yml
index f39abef..84def5d 100644
--- a/.github/workflows/nightly.yml
+++ b/.github/workflows/nightly.yml
@@ -12,12 +12,12 @@ jobs:
     - name: Checkout
       uses: actions/checkout@v2
     - name: SPM tests
-      run: swift test --sanitize=thread
+      run: swift test
   linux:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        image: ['nightly-5.6-bionic', 'nightly-5.6-focal', 'nightly-5.6-centos8', 'nightly-5.6-amazonlinux2']
+        image: ['nightly-bionic', 'nightly-focal', 'nightly-centos8', 'nightly-amazonlinux2']
     
     container:
       image: swiftlang/swift:${{ matrix.image }}
diff --git a/.swiftformat b/.swiftformat
index fbc7bb8..3a7c14d 100644
--- a/.swiftformat
+++ b/.swiftformat
@@ -23,4 +23,4 @@
 --wrapcollections before-first
 
 #file header
-#--header "//===----------------------------------------------------------------------===//\n//\n// This source file is part of the Hummingbird server framework project\n//\n// Copyright (c) {created.year}-{year} the Hummingbird authors\n// Licensed under Apache License v2.0\n//\n// See LICENSE.txt for license information\n// See hummingbird/CONTRIBUTORS.txt for the list of Hummingbird authors\n//\n// SPDX-License-Identifier: Apache-2.0\n//\n//===----------------------------------------------------------------------===//"
+# --header "//===----------------------------------------------------------------------===//\n//\n// This source file is part of the Hummingbird server framework project\n//\n// Copyright (c) {created.year}-{year} the Hummingbird authors\n// Licensed under Apache License v2.0\n//\n// See LICENSE.txt for license information\n// See hummingbird/CONTRIBUTORS.txt for the list of Hummingbird authors\n//\n// SPDX-License-Identifier: Apache-2.0\n//\n//===----------------------------------------------------------------------===//"
diff --git a/Tests/LinuxMain.swift b/Tests/LinuxMain.swift
deleted file mode 100644
index 7737b98..0000000
--- a/Tests/LinuxMain.swift
+++ /dev/null
@@ -1,13 +0,0 @@
-//===----------------------------------------------------------------------===//
-//
-// This source file is part of the Hummingbird server framework project
-//
-// Copyright (c) 2021-2021 the Hummingbird authors
-// Licensed under Apache License v2.0
-//
-// See LICENSE.txt for license information
-// See hummingbird/CONTRIBUTORS.txt for the list of Hummingbird authors
-//
-// SPDX-License-Identifier: Apache-2.0
-//
-//===----------------------------------------------------------------------===//
diff --git a/scripts/validate.sh b/scripts/validate.sh
index 36960a8..e201bd3 100755
--- a/scripts/validate.sh
+++ b/scripts/validate.sh
@@ -22,7 +22,7 @@ which swiftformat > /dev/null 2>&1 || (echo "swiftformat not installed. You can
 
 function replace_acceptable_years() {
     # this needs to replace all acceptable forms with 'YEARS'
-    sed -e 's/20[12][78901]-20[12][8901]/YEARS/' -e 's/20[12][8901]/YEARS/' -e '/^#!/ d'
+    sed -e 's/20[12][0-9]-20[12][0-9]/YEARS/' -e 's/20[12][0-9]/YEARS/' -e '/^#!/ d'
 }
 
 printf "=> Checking format... "