diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 68d7cd18..36799584 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -24,8 +24,8 @@ jobs:
     steps:
       - name: Check out package
         uses: actions/checkout@v2
-      - name: Run unit tests with code coverage
-        run: swift test --enable-test-discovery --filter=^PostgresNIOTests --enable-code-coverage
+      - name: Run unit tests with code coverage and Thread Sanitizer
+        run: swift test --enable-test-discovery --filter=^PostgresNIOTests --sanitize=thread --enable-code-coverage
       - name: Convert code coverage report to most expressive format
         run: |
           export pkgname="$(swift package dump-package | perl -e 'use JSON::PP; print (decode_json(join("",(<>)))->{name});')" \
@@ -33,9 +33,9 @@ jobs:
                  exc_prefix="$(which xcrun || true)" && \
           ${exc_prefix} llvm-cov export -format lcov \
               -instr-profile="$(dirname "$(swift test --show-codecov-path)")/default.profdata" \
-              --ignore-filename-regex='/\.build/' --ignore-filename-regex='/Tests/' \
+              --ignore-filename-regex='/(\.build|Tests)/' \
               "$(swift build --show-bin-path)/${pkgname}PackageTests.xctest${subpath}" >"${pkgname}.lcov"
-          echo "CODECOV_FILE=$(pwd)/${pkgname}.lcov" >> $GITHUB_ENV
+          echo "CODECOV_FILE=$(pwd)/${pkgname}.lcov" >> "${GITHUB_ENV}"
       - name: Send coverage report to codecov.io
         uses: codecov/codecov-action@v2
         with:
@@ -58,7 +58,8 @@ jobs:
           - md5
           - scram-sha-256
         swiftver:
-          - swift:5.2
+          # Only test latest Swift for integration tests, issues from older Swift versions that don't show
+          # up in the unit tests are fairly unlikely.
           - swift:5.5
         swiftos:
           - focal
@@ -67,18 +68,16 @@ jobs:
     env:
       LOG_LEVEL: debug
       # Unfortunately, fluent-postgres-driver details leak through here
-      POSTGRES_HOSTNAME: 'psql-a'
       POSTGRES_DB: 'test_database'
-      POSTGRES_DATABASE: 'test_database'
-      POSTGRES_DATABASE_A: 'test_database'
-      POSTGRES_DATABASE_B: 'test_database'
+      POSTGRES_DB_A: 'test_database'
+      POSTGRES_DB_B: 'test_database'
       POSTGRES_USER: 'test_username'
-      POSTGRES_USERNAME: 'test_username'
-      POSTGRES_USERNAME_A: 'test_username'
-      POSTGRES_USERNAME_B: 'test_username'
+      POSTGRES_USER_A: 'test_username'
+      POSTGRES_USER_B: 'test_username'
       POSTGRES_PASSWORD: 'test_password'
       POSTGRES_PASSWORD_A: 'test_password'
       POSTGRES_PASSWORD_B: 'test_password'
+      POSTGRES_HOSTNAME: 'psql-a'
       POSTGRES_HOSTNAME_A: 'psql-a'
       POSTGRES_HOSTNAME_B: 'psql-b'
       POSTGRES_HOST_AUTH_METHOD: ${{ matrix.dbauth }}
@@ -104,7 +103,7 @@ jobs:
         uses: actions/checkout@v2
         with: { path: 'postgres-nio' }
       - name: Run integration tests
-        run: swift test --package-path postgres-nio --enable-test-discovery --filter=^IntegrationTests
+        run: swift test --package-path postgres-nio --filter=^IntegrationTests
       - name: Check out postgres-kit dependent
         uses: actions/checkout@v2
         with: { repository: 'vapor/postgres-kit', path: 'postgres-kit' }
@@ -116,9 +115,9 @@ jobs:
           swift package --package-path postgres-kit edit postgres-nio --path postgres-nio
           swift package --package-path fluent-postgres-driver edit postgres-nio --path postgres-nio
       - name: Run postgres-kit tests
-        run: swift test --package-path postgres-kit --enable-test-discovery
+        run: swift test --package-path postgres-kit
       - name: Run fluent-postgres-driver tests
-        run: swift test --package-path fluent-postgres-driver --enable-test-discovery
+        run: swift test --package-path fluent-postgres-driver
 
   macos-all:
     strategy:
@@ -148,8 +147,8 @@ jobs:
           xcode-version: ${{ matrix.xcode }}
       - name: Install Postgres, setup DB and auth, and wait for server start
         run: |
-          export PATH="$(brew prefix)/opt/${{ matrix.dbimage }}/bin:$PATH" PGDATA=/tmp/vapor-postgres-test
-          brew install ${{ matrix.dbimage }}
+          export PATH="$(brew --prefix)/opt/${{ matrix.dbimage }}/bin:$PATH" PGDATA=/tmp/vapor-postgres-test
+          (brew unlink postgresql || true) && brew install ${{ matrix.dbimage }} && brew link --force ${{ matrix.dbimage }}
           initdb --locale=C --auth-host ${{ matrix.dbauth }} -U $POSTGRES_USER --pwfile=<(echo $POSTGRES_PASSWORD)
           pg_ctl start --wait
         timeout-minutes: 2