From 587a09d7f8ffb0614cbb8d845c595deb44a9cc99 Mon Sep 17 00:00:00 2001
From: Rick Newton-Rogers <rnro@apple.com>
Date: Fri, 19 Sep 2025 10:51:11 +0100
Subject: [PATCH 01/27] first pass

---
 .github/workflows/swift_test_matrix.yml | 65 +++++++++++++++------
 scripts/generate_matrix.sh              | 75 +++++++++++++++++++++----
 2 files changed, 113 insertions(+), 27 deletions(-)

diff --git a/.github/workflows/swift_test_matrix.yml b/.github/workflows/swift_test_matrix.yml
index 4d0a12bff9..d1f16f69d0 100644
--- a/.github/workflows/swift_test_matrix.yml
+++ b/.github/workflows/swift_test_matrix.yml
@@ -41,15 +41,30 @@ jobs:
             setup_command_expression=""
           fi
           workspace="/$(basename ${{ github.workspace }})"
-          docker run -v ${{ github.workspace }}:"$workspace" \
-            -w "$workspace" \
-            -e CI="$CI" \
-            -e GITHUB_ACTIONS="$GITHUB_ACTIONS" \
-            -e SWIFT_VERSION="${{ matrix.config.swift_version }}" \
-            -e setup_command_expression="$setup_command_expression" \
-            -e workspace="$workspace" \
-            ${{ matrix.config.image }} \
-            bash -c "$setup_command_expression ${{ matrix.config.command }} ${{ matrix.config.command_arguments }}"
+
+          docker_args=(
+            "run"
+            "-v" "${{ github.workspace }}:$workspace"
+            "-w" "$workspace"
+            "-e" "CI=$CI"
+            "-e" "GITHUB_ACTIONS=$GITHUB_ACTIONS"
+            "-e" "SWIFT_VERSION=${{ matrix.config.swift_version }}"
+            "-e" "setup_command_expression=$setup_command_expression"
+            "-e" "workspace=$workspace"
+          )
+
+          if [[ '${{ toJson(matrix.config.env) }}' != '{}' ]]; then
+            while IFS="=" read -r key value; do
+              if [[ -n "$key" && -n "$value" ]]; then
+                docker_args+=("-e" "$key=$value")
+              fi
+            done < <(echo '${{ toJson(matrix.config.env) }}' | jq -r 'to_entries[] | "\(.key)=\(.value)"')
+          fi
+
+          docker_args+=("${{ matrix.config.image }}")
+          docker_args+=("bash" "-c" "$setup_command_expression ${{ matrix.config.command }} ${{ matrix.config.command_arguments }}")
+
+          docker "${docker_args[@]}"
       - name: Run matrix job (Windows)
         if: ${{ matrix.config.platform == 'Windows' }}
         run: |
@@ -59,13 +74,29 @@ jobs:
               $setup_command_expression = ""
           }
           $workspace = "C:\" + (Split-Path ${{ github.workspace }} -Leaf)
-          docker run -v ${{ github.workspace }}:$($workspace) `
-            -w $($workspace) `
-            -e CI=%CI% `
-            -e GITHUB_ACTIONS=%GITHUB_ACTIONS% `
-            -e SWIFT_VERSION="${{ matrix.config.swift_version }}" `
-            -e setup_command_expression=%setup_command_expression% `
-            ${{ matrix.config.image }} `
-            cmd /s /c  "swift --version & $($setup_command_expression) ${{ matrix.config.command }} ${{ matrix.config.command_arguments }}"
+
+          $docker_args = @(
+              "run", "-v", "${{ github.workspace }}:$($workspace)",
+              "-w", $workspace,
+              "-e", "CI=%CI%",
+              "-e", "GITHUB_ACTIONS=%GITHUB_ACTIONS%",
+              "-e", "SWIFT_VERSION=${{ matrix.config.swift_version }}",
+              "-e", "setup_command_expression=%setup_command_expression%"
+          )
+
+          $env_args = @()
+          $env_json = '${{ toJson(matrix.config.env) }}'
+          if ($env_json -ne '{}') {
+              $env_obj = $env_json | ConvertFrom-Json
+              $env_obj.PSObject.Properties | ForEach-Object {
+                  $env_args += "-e"
+                  $env_args += "$($_.Name)=$($_.Value)"
+              }
+          }
+          $docker_args += $env_args
+
+          $docker_args += @("${{ matrix.config.image }}", "cmd", "/s", "/c", "swift --version & $($setup_command_expression) ${{ matrix.config.command }} ${{ matrix.config.command_arguments }}")
+
+          & docker @docker_args
     env:
       SWIFT_VERSION: ${{ matrix.config.swift_version }}
diff --git a/scripts/generate_matrix.sh b/scripts/generate_matrix.sh
index 2ef13b5fe4..abb5f84a06 100755
--- a/scripts/generate_matrix.sh
+++ b/scripts/generate_matrix.sh
@@ -16,6 +16,9 @@
 # Parameters
 linux_command="$MATRIX_LINUX_COMMAND"  # required if any Linux pipeline is enabled
 linux_setup_command="$MATRIX_LINUX_SETUP_COMMAND"
+linux_env_vars="$MATRIX_LINUX_ENV_VARS"
+linux_env_var_pair_separator="${MATRIX_LINUX_ENV_VAR_PAIR_SEPARATOR:="="}"
+linux_env_var_list_separator="${MATRIX_LINUX_ENV_VAR_LIST_SEPARATOR:=","}"
 linux_5_9_enabled="${MATRIX_LINUX_5_9_ENABLED:=false}"
 linux_5_9_command_arguments="$MATRIX_LINUX_5_9_COMMAND_ARGUMENTS"
 linux_5_10_enabled="${MATRIX_LINUX_5_10_ENABLED:=true}"
@@ -33,6 +36,9 @@ linux_nightly_main_command_arguments="$MATRIX_LINUX_NIGHTLY_MAIN_COMMAND_ARGUMEN
 
 windows_command="$MATRIX_WINDOWS_COMMAND"  # required if any Windows pipeline is enabled
 windows_setup_command="$MATRIX_WINDOWS_SETUP_COMMAND"
+windows_env_vars="$MATRIX_WINDOWS_ENV_VARS"
+windows_env_var_pair_separator="${MATRIX_WINDOWS_ENV_VAR_PAIR_SEPARATOR:="="}"
+windows_env_var_list_separator="${MATRIX_WINDOWS_ENV_VAR_LIST_SEPARATOR:=","}"
 windows_6_0_enabled="${MATRIX_WINDOWS_6_0_ENABLED:=false}"
 windows_6_1_enabled="${MATRIX_WINDOWS_6_1_ENABLED:=false}"
 windows_6_2_enabled="${MATRIX_WINDOWS_6_2_ENABLED:=false}"
@@ -44,6 +50,10 @@ windows_nightly_next_command_arguments="${MATRIX_WINDOWS_NIGHTLY_NEXT_COMMAND_AR
 windows_nightly_main_enabled="${MATRIX_WINDOWS_NIGHTLY_MAIN_ENABLED:=false}"
 windows_nightly_main_command_arguments="$MATRIX_WINDOWS_NIGHTLY_MAIN_COMMAND_ARGUMENTS"
 
+# Specifying custom environment variables example:
+#   MATRIX_WINDOWS_ENV_VARS="BUILD:Release;ARCH:x64" MATRIX_WINDOWS_ENV_VAR_PAIR_SEPARATOR=":" MATRIX_WINDOWS_ENV_VAR_LIST_SEPARATOR=";" ./generate_matrix.sh
+
+
 # Defaults
 linux_runner="ubuntu-latest"
 linux_5_9_container_image="swift:5.9-jammy"
@@ -65,6 +75,40 @@ windows_nightly_next_container_image="swiftlang/swift:nightly-6.2-windowsserverc
 windows_nightly_main_runner="windows-2022"
 windows_nightly_main_container_image="swiftlang/swift:nightly-main-windowsservercore-ltsc2022"
 
+# Function to parse environment variables and convert to JSON object
+parse_env_vars() {
+  local env_vars="$1"
+  local pair_separator="$2"
+  local list_separator="$3"
+
+  if [[ -z "$env_vars" ]]; then
+    echo "{}"
+    return
+  fi
+
+  local json_obj="{}"
+
+  # Split the env_vars string by list_separator
+  IFS="$list_separator" read -ra env_pairs <<< "$env_vars"
+
+  for pair in "${env_pairs[@]}"; do
+    # Split each pair by pair_separator
+    IFS="$pair_separator" read -ra kv <<< "$pair"
+    if [[ ${#kv[@]} -eq 2 ]]; then
+      local key="${kv[0]}"
+      local value="${kv[1]}"
+      # Add to JSON object using jq
+      json_obj=$(echo "$json_obj" | jq -c --arg key "$key" --arg value "$value" '. + {($key): $value}')
+    fi
+  done
+
+  echo "$json_obj"
+}
+
+# Parse environment variables for Linux and Windows
+linux_env_vars_json=$(parse_env_vars "$linux_env_vars" "$linux_env_var_pair_separator" "$linux_env_var_list_separator")
+windows_env_vars_json=$(parse_env_vars "$windows_env_vars" "$windows_env_var_pair_separator" "$windows_env_var_list_separator")
+
 # Create matrix from inputs
 matrix='{"config": []}'
 
@@ -91,7 +135,8 @@ if [[ "$linux_5_9_enabled" == "true" ]]; then
     --arg command_arguments "$linux_5_9_command_arguments" \
     --arg container_image "$linux_5_9_container_image" \
     --arg runner "$linux_runner" \
-    '.config[.config| length] |= . + { "name": "5.9", "image": $container_image, "swift_version": "5.9", "platform": "Linux", "command": $command, "command_arguments": $command_arguments, "setup_command": $setup_command, "runner": $runner}')
+    --argjson env_vars "$linux_env_vars_json" \
+    '.config[.config| length] |= . + { "name": "5.9", "image": $container_image, "swift_version": "5.9", "platform": "Linux", "command": $command, "command_arguments": $command_arguments, "setup_command": $setup_command, "runner": $runner, "env": $env_vars}')
 fi
 
 if [[ "$linux_5_10_enabled" == "true" ]]; then
@@ -101,7 +146,8 @@ if [[ "$linux_5_10_enabled" == "true" ]]; then
     --arg command_arguments "$linux_5_10_command_arguments" \
     --arg container_image "$linux_5_10_container_image" \
     --arg runner "$linux_runner" \
-    '.config[.config| length] |= . + { "name": "5.10", "image": $container_image, "swift_version": "5.10", "platform": "Linux", "command": $command, "command_arguments": $command_arguments, "setup_command": $setup_command, "runner": $runner}')
+    --argjson env_vars "$linux_env_vars_json" \
+    '.config[.config| length] |= . + { "name": "5.10", "image": $container_image, "swift_version": "5.10", "platform": "Linux", "command": $command, "command_arguments": $command_arguments, "setup_command": $setup_command, "runner": $runner, "env": $env_vars}')
 fi
 
 if [[ "$linux_6_0_enabled" == "true" ]]; then
@@ -111,7 +157,8 @@ if [[ "$linux_6_0_enabled" == "true" ]]; then
     --arg command_arguments "$linux_6_0_command_arguments" \
     --arg container_image "$linux_6_0_container_image" \
     --arg runner "$linux_runner" \
-    '.config[.config| length] |= . + { "name": "6.0", "image": $container_image, "swift_version": "6.0", "platform": "Linux", "command": $command, "command_arguments": $command_arguments, "setup_command": $setup_command, "runner": $runner}')
+    --argjson env_vars "$linux_env_vars_json" \
+    '.config[.config| length] |= . + { "name": "6.0", "image": $container_image, "swift_version": "6.0", "platform": "Linux", "command": $command, "command_arguments": $command_arguments, "setup_command": $setup_command, "runner": $runner, "env": $env_vars}')
 fi
 
 if [[ "$linux_6_1_enabled" == "true" ]]; then
@@ -121,7 +168,8 @@ if [[ "$linux_6_1_enabled" == "true" ]]; then
     --arg command_arguments "$linux_6_1_command_arguments" \
     --arg container_image "$linux_6_1_container_image" \
     --arg runner "$linux_runner" \
-    '.config[.config| length] |= . + { "name": "6.1", "image": $container_image, "swift_version": "6.1", "platform": "Linux", "command": $command, "command_arguments": $command_arguments, "setup_command": $setup_command, "runner": $runner}')
+    --argjson env_vars "$linux_env_vars_json" \
+    '.config[.config| length] |= . + { "name": "6.1", "image": $container_image, "swift_version": "6.1", "platform": "Linux", "command": $command, "command_arguments": $command_arguments, "setup_command": $setup_command, "runner": $runner, "env": $env_vars}')
 fi
 
 if [[ "$linux_6_2_enabled" == "true" ]]; then
@@ -141,7 +189,8 @@ if [[ "$linux_nightly_next_enabled" == "true" ]]; then
     --arg command_arguments "$linux_nightly_next_command_arguments" \
     --arg container_image "$linux_nightly_next_container_image" \
     --arg runner "$linux_runner" \
-    '.config[.config| length] |= . + { "name": "nightly-next", "image": $container_image, "swift_version": "nightly-next", "platform": "Linux", "command": $command, "command_arguments": $command_arguments, "setup_command": $setup_command, "runner": $runner}')
+    --argjson env_vars "$linux_env_vars_json" \
+    '.config[.config| length] |= . + { "name": "nightly-next", "image": $container_image, "swift_version": "nightly-next", "platform": "Linux", "command": $command, "command_arguments": $command_arguments, "setup_command": $setup_command, "runner": $runner, "env": $env_vars}')
 fi
 
 if [[ "$linux_nightly_main_enabled" == "true" ]]; then
@@ -151,12 +200,14 @@ if [[ "$linux_nightly_main_enabled" == "true" ]]; then
     --arg command_arguments "$linux_nightly_main_command_arguments" \
     --arg container_image "$linux_nightly_main_container_image" \
     --arg runner "$linux_runner" \
-    '.config[.config| length] |= . + { "name": "nightly-main", "image": $container_image, "swift_version": "nightly-main", "platform": "Linux", "command": $command, "command_arguments": $command_arguments, "setup_command": $setup_command, "runner": $runner}')
+    --argjson env_vars "$linux_env_vars_json" \
+    '.config[.config| length] |= . + { "name": "nightly-main", "image": $container_image, "swift_version": "nightly-main", "platform": "Linux", "command": $command, "command_arguments": $command_arguments, "setup_command": $setup_command, "runner": $runner, "env": $env_vars}')
 fi
 
 ## Windows
 if [[ \
   "$windows_6_0_enabled" == "true" || \
+  "$windows_6_1_enabled" == "true" || \
   "$windows_nightly_next_enabled" == "true" || \
   "$windows_nightly_main_enabled" == "true" \
 ]]; then
@@ -172,7 +223,8 @@ if [[ "$windows_6_0_enabled" == "true" ]]; then
     --arg command_arguments "$windows_6_0_command_arguments" \
     --arg container_image "$windows_6_0_container_image" \
     --arg runner "$windows_6_0_runner" \
-    '.config[.config| length] |= . + { "name": "6.0", "image": $container_image, "swift_version": "6.0", "platform": "Windows", "command": $command, "command_arguments": $command_arguments, "setup_command": $setup_command, "runner": $runner }')
+    --argjson env_vars "$windows_env_vars_json" \
+    '.config[.config| length] |= . + { "name": "6.0", "image": $container_image, "swift_version": "6.0", "platform": "Windows", "command": $command, "command_arguments": $command_arguments, "setup_command": $setup_command, "runner": $runner, "env": $env_vars }')
 fi
 
 if [[ "$windows_6_1_enabled" == "true" ]]; then
@@ -182,7 +234,8 @@ if [[ "$windows_6_1_enabled" == "true" ]]; then
     --arg command_arguments "$windows_6_1_command_arguments" \
     --arg container_image "$windows_6_1_container_image" \
     --arg runner "$windows_6_1_runner" \
-    '.config[.config| length] |= . + { "name": "6.1", "image": $container_image, "swift_version": "6.1", "platform": "Windows", "command": $command, "command_arguments": $command_arguments, "setup_command": $setup_command, "runner": $runner }')
+    --argjson env_vars "$windows_env_vars_json" \
+    '.config[.config| length] |= . + { "name": "6.1", "image": $container_image, "swift_version": "6.1", "platform": "Windows", "command": $command, "command_arguments": $command_arguments, "setup_command": $setup_command, "runner": $runner, "env": $env_vars }')
 fi
 
 if [[ "$windows_6_2_enabled" == "true" ]]; then
@@ -202,7 +255,8 @@ if [[ "$windows_nightly_next_enabled" == "true" ]]; then
     --arg command_arguments "$windows_nightly_next_command_arguments" \
     --arg container_image "$windows_nightly_next_container_image" \
     --arg runner "$windows_nightly_next_runner" \
-    '.config[.config| length] |= . + { "name": "nightly-next", "image": $container_image, "swift_version": "nightly-next", "platform": "Windows", "command": $command, "command_arguments": $command_arguments, "setup_command": $setup_command, "runner": $runner }')
+    --argjson env_vars "$windows_env_vars_json" \
+    '.config[.config| length] |= . + { "name": "nightly-next", "image": $container_image, "swift_version": "nightly-next", "platform": "Windows", "command": $command, "command_arguments": $command_arguments, "setup_command": $setup_command, "runner": $runner, "env": $env_vars }')
 fi
 
 if [[ "$windows_nightly_main_enabled" == "true" ]]; then
@@ -212,7 +266,8 @@ if [[ "$windows_nightly_main_enabled" == "true" ]]; then
     --arg command_arguments "$windows_nightly_main_command_arguments" \
     --arg container_image "$windows_nightly_main_container_image" \
     --arg runner "$windows_nightly_main_runner" \
-    '.config[.config| length] |= . + { "name": "nightly-main", "image": $container_image, "swift_version": "nightly-main", "platform": "Windows", "command": $command, "command_arguments": $command_arguments, "setup_command": $setup_command, "runner": $runner }')
+    --argjson env_vars "$windows_env_vars_json" \
+    '.config[.config| length] |= . + { "name": "nightly-main", "image": $container_image, "swift_version": "nightly-main", "platform": "Windows", "command": $command, "command_arguments": $command_arguments, "setup_command": $setup_command, "runner": $runner, "env": $env_vars }')
 fi
 
 echo "$matrix" | jq -c

From 12f15fd19d7128ea5b1cc0239685056def4fd6df Mon Sep 17 00:00:00 2001
From: Rick Newton-Rogers <rnro@apple.com>
Date: Fri, 19 Sep 2025 10:59:50 +0100
Subject: [PATCH 02/27] log docker command

---
 .github/workflows/swift_test_matrix.yml | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/.github/workflows/swift_test_matrix.yml b/.github/workflows/swift_test_matrix.yml
index d1f16f69d0..066939ab3e 100644
--- a/.github/workflows/swift_test_matrix.yml
+++ b/.github/workflows/swift_test_matrix.yml
@@ -64,6 +64,7 @@ jobs:
           docker_args+=("${{ matrix.config.image }}")
           docker_args+=("bash" "-c" "$setup_command_expression ${{ matrix.config.command }} ${{ matrix.config.command_arguments }}")
 
+          echo "Executing Docker command: docker ${docker_args[*]}"
           docker "${docker_args[@]}"
       - name: Run matrix job (Windows)
         if: ${{ matrix.config.platform == 'Windows' }}
@@ -97,6 +98,7 @@ jobs:
 
           $docker_args += @("${{ matrix.config.image }}", "cmd", "/s", "/c", "swift --version & $($setup_command_expression) ${{ matrix.config.command }} ${{ matrix.config.command_arguments }}")
 
+          Write-Host "Executing Docker command: docker $($docker_args -join ' ')"
           & docker @docker_args
     env:
       SWIFT_VERSION: ${{ matrix.config.swift_version }}

From 18cdfc0f4701dda8a268f3345a9cfcd2589715e0 Mon Sep 17 00:00:00 2001
From: Rick Newton-Rogers <rnro@apple.com>
Date: Fri, 19 Sep 2025 11:14:27 +0100
Subject: [PATCH 03/27] don't expose setup command as env var

---
 .github/workflows/swift_test_matrix.yml | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/.github/workflows/swift_test_matrix.yml b/.github/workflows/swift_test_matrix.yml
index 066939ab3e..e0f49e752b 100644
--- a/.github/workflows/swift_test_matrix.yml
+++ b/.github/workflows/swift_test_matrix.yml
@@ -49,7 +49,6 @@ jobs:
             "-e" "CI=$CI"
             "-e" "GITHUB_ACTIONS=$GITHUB_ACTIONS"
             "-e" "SWIFT_VERSION=${{ matrix.config.swift_version }}"
-            "-e" "setup_command_expression=$setup_command_expression"
             "-e" "workspace=$workspace"
           )
 
@@ -81,8 +80,7 @@ jobs:
               "-w", $workspace,
               "-e", "CI=%CI%",
               "-e", "GITHUB_ACTIONS=%GITHUB_ACTIONS%",
-              "-e", "SWIFT_VERSION=${{ matrix.config.swift_version }}",
-              "-e", "setup_command_expression=%setup_command_expression%"
+              "-e", "SWIFT_VERSION=${{ matrix.config.swift_version }}"
           )
 
           $env_args = @()

From 10501ca69035e4230f8ba70b47395ce7f5c53da9 Mon Sep 17 00:00:00 2001
From: Rick Newton-Rogers <rnro@apple.com>
Date: Fri, 19 Sep 2025 11:15:15 +0100
Subject: [PATCH 04/27] test env vars

---
 .github/workflows/unit_tests.yml | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/.github/workflows/unit_tests.yml b/.github/workflows/unit_tests.yml
index a94073307e..a3a080c31a 100644
--- a/.github/workflows/unit_tests.yml
+++ b/.github/workflows/unit_tests.yml
@@ -149,6 +149,7 @@ jobs:
         env:
           MATRIX_LINUX_SETUP_COMMAND: "swift --version"
           MATRIX_LINUX_COMMAND: "swift test"
+          MATRIX_LINUX_ENV_VARS: "TEST_VAR_DEBUG=1,TEST_VAR_LOG_LEVEL=info"  # TODO: remove, testing
           MATRIX_LINUX_5_9_ENABLED: ${{ inputs.linux_5_9_enabled }}
           MATRIX_LINUX_5_9_COMMAND_ARGUMENTS: ${{ inputs.linux_5_9_arguments_override }}
           MATRIX_LINUX_5_10_ENABLED: ${{ inputs.linux_5_10_enabled }}
@@ -164,6 +165,7 @@ jobs:
           MATRIX_LINUX_NIGHTLY_MAIN_ENABLED: ${{ inputs.linux_nightly_main_enabled }}
           MATRIX_LINUX_NIGHTLY_MAIN_COMMAND_ARGUMENTS: ${{ inputs.linux_nightly_main_arguments_override }}
           MATRIX_WINDOWS_COMMAND: "swift test"
+          MATRIX_WINDOWS_ENV_VARS: "TEST_VAR_DEBUG=1,TEST_VAR_LOG_LEVEL=info"  # TODO: remove, testing
           MATRIX_WINDOWS_6_0_ENABLED: ${{ inputs.windows_6_0_enabled }}
           MATRIX_WINDOWS_6_0_COMMAND_ARGUMENTS: ${{ inputs.windows_6_0_arguments_override }}
           MATRIX_WINDOWS_6_1_ENABLED: ${{ inputs.windows_6_1_enabled }}

From 11959c3b103543f50fcaea88815f03c48301c477 Mon Sep 17 00:00:00 2001
From: Rick Newton-Rogers <rnro@apple.com>
Date: Fri, 19 Sep 2025 11:58:03 +0100
Subject: [PATCH 05/27] wire up env var parameters

---
 .github/workflows/benchmarks.yml | 31 +++++++++++++++++++++++++++++++
 .github/workflows/static_sdk.yml |  6 ++++--
 .github/workflows/unit_tests.yml | 31 +++++++++++++++++++++++++++++++
 3 files changed, 66 insertions(+), 2 deletions(-)

diff --git a/.github/workflows/benchmarks.yml b/.github/workflows/benchmarks.yml
index 19bc0391a0..0a0d5ae633 100644
--- a/.github/workflows/benchmarks.yml
+++ b/.github/workflows/benchmarks.yml
@@ -68,6 +68,31 @@ on:
         description: "Boolean to enable the Windows nightly main Swift version matrix job. Currently has no effect!"  # TODO: implement Windows benchmarking
         default: false
 
+      linux_env_vars:
+        type: string
+        description: "Environment variables for Linux jobs (e.g., 'DEBUG=1,LOG_LEVEL=info')."
+        default: ""
+      linux_env_var_pair_separator:
+        type: string
+        description: "Separator between key and value for Linux environment variables."
+        default: "="
+      linux_env_var_list_separator:
+        type: string
+        description: "Separator between environment variable pairs for Linux."
+        default: ","
+      windows_env_vars:
+        type: string
+        description: "Environment variables for Windows jobs (e.g., 'DEBUG=1,LOG_LEVEL=info')."
+        default: ""
+      windows_env_var_pair_separator:
+        type: string
+        description: "Separator between key and value for Windows environment variables."
+        default: "="
+      windows_env_var_list_separator:
+        type: string
+        description: "Separator between environment variable pairs for Windows."
+        default: ","
+
 jobs:
   construct-matrix:
     name: Construct Benchmarks matrix
@@ -84,6 +109,9 @@ jobs:
         env:
           MATRIX_LINUX_COMMAND: "curl -s https://raw.githubusercontent.com/apple/swift-nio/main/scripts/check_benchmark_thresholds.sh | BENCHMARK_PACKAGE_PATH=${{ inputs.benchmark_package_path }} bash"
           MATRIX_LINUX_SETUP_COMMAND: "swift --version && apt-get update -y -q && apt-get install -y -q curl libjemalloc-dev && git config --global --add safe.directory /$(basename ${{ github.workspace }})"
+          MATRIX_LINUX_ENV_VARS: ${{ inputs.linux_env_vars }}
+          MATRIX_LINUX_ENV_VAR_PAIR_SEPARATOR: ${{ inputs.linux_env_var_pair_separator }}
+          MATRIX_LINUX_ENV_VAR_LIST_SEPARATOR: ${{ inputs.linux_env_var_list_separator }}
           MATRIX_LINUX_5_9_ENABLED: ${{ inputs.linux_5_9_enabled }}
           MATRIX_LINUX_5_10_ENABLED: ${{ inputs.linux_5_10_enabled }}
           MATRIX_LINUX_6_0_ENABLED: ${{ inputs.linux_6_0_enabled }}
@@ -91,6 +119,9 @@ jobs:
           MATRIX_LINUX_6_2_ENABLED: ${{ inputs.linux_6_2_enabled }}
           MATRIX_LINUX_NIGHTLY_NEXT_ENABLED: ${{ inputs.linux_nightly_6_1_enabled && inputs.linux_nightly_next_enabled  }}
           MATRIX_LINUX_NIGHTLY_MAIN_ENABLED: ${{ inputs.linux_nightly_main_enabled }}
+          MATRIX_WINDOWS_ENV_VARS: ${{ inputs.windows_env_vars }}
+          MATRIX_WINDOWS_ENV_VAR_PAIR_SEPARATOR: ${{ inputs.windows_env_var_pair_separator }}
+          MATRIX_WINDOWS_ENV_VAR_LIST_SEPARATOR: ${{ inputs.windows_env_var_list_separator }}
 
   benchmarks:
     name: Benchmarks
diff --git a/.github/workflows/static_sdk.yml b/.github/workflows/static_sdk.yml
index b00477abe9..6c76b97c0d 100644
--- a/.github/workflows/static_sdk.yml
+++ b/.github/workflows/static_sdk.yml
@@ -21,7 +21,8 @@ jobs:
               "image":"ubuntu:jammy",
               "setup_command":"apt update -q && apt install -y -q curl jq tar && curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/install_swift_prerequisites.sh | bash && curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/install_static_sdk.sh | INSTALL_SWIFT_STATIC_SDK_VERSION=latest INSTALL_SWIFT_STATIC_SDK_ARCH=x86_64 bash && hash -r",
               "command":"swift build",
-              "command_arguments":"--swift-sdk x86_64-swift-linux-musl"
+              "command_arguments":"--swift-sdk x86_64-swift-linux-musl",
+              "env":{}
             },
             {
               "name":"main Jammy",
@@ -31,7 +32,8 @@ jobs:
               "image":"ubuntu:jammy",
               "setup_command":"apt update -q && apt install -y -q curl jq tar && curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/install_swift_prerequisites.sh | bash && curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/install_static_sdk.sh | INSTALL_SWIFT_STATIC_SDK_BRANCH=main INSTALL_SWIFT_STATIC_SDK_ARCH=x86_64 bash && hash -r",
               "command":"swift build",
-              "command_arguments":"--swift-sdk x86_64-swift-linux-musl"
+              "command_arguments":"--swift-sdk x86_64-swift-linux-musl",
+              "env":{}
             }
           ]
         }
diff --git a/.github/workflows/unit_tests.yml b/.github/workflows/unit_tests.yml
index a3a080c31a..4ef6723900 100644
--- a/.github/workflows/unit_tests.yml
+++ b/.github/workflows/unit_tests.yml
@@ -133,6 +133,31 @@ on:
         description: "The arguments passed to swift test in the Windows nightly main Swift version matrix job."
         default: ""
 
+      linux_env_vars:
+        type: string
+        description: "Environment variables for Linux jobs (e.g., 'DEBUG=1,LOG_LEVEL=info')."
+        default: ""
+      linux_env_var_pair_separator:
+        type: string
+        description: "Separator between key and value for Linux environment variables."
+        default: "="
+      linux_env_var_list_separator:
+        type: string
+        description: "Separator between environment variable pairs for Linux."
+        default: ","
+      windows_env_vars:
+        type: string
+        description: "Environment variables for Windows jobs (e.g., 'DEBUG=1,LOG_LEVEL=info')."
+        default: ""
+      windows_env_var_pair_separator:
+        type: string
+        description: "Separator between key and value for Windows environment variables."
+        default: "="
+      windows_env_var_list_separator:
+        type: string
+        description: "Separator between environment variable pairs for Windows."
+        default: ","
+
 jobs:
   construct-matrix:
     name: Construct unit test matrix
@@ -150,6 +175,9 @@ jobs:
           MATRIX_LINUX_SETUP_COMMAND: "swift --version"
           MATRIX_LINUX_COMMAND: "swift test"
           MATRIX_LINUX_ENV_VARS: "TEST_VAR_DEBUG=1,TEST_VAR_LOG_LEVEL=info"  # TODO: remove, testing
+        #   MATRIX_LINUX_ENV_VARS: ${{ inputs.linux_env_vars }}
+          MATRIX_LINUX_ENV_VAR_PAIR_SEPARATOR: ${{ inputs.linux_env_var_pair_separator }}
+          MATRIX_LINUX_ENV_VAR_LIST_SEPARATOR: ${{ inputs.linux_env_var_list_separator }}
           MATRIX_LINUX_5_9_ENABLED: ${{ inputs.linux_5_9_enabled }}
           MATRIX_LINUX_5_9_COMMAND_ARGUMENTS: ${{ inputs.linux_5_9_arguments_override }}
           MATRIX_LINUX_5_10_ENABLED: ${{ inputs.linux_5_10_enabled }}
@@ -166,6 +194,9 @@ jobs:
           MATRIX_LINUX_NIGHTLY_MAIN_COMMAND_ARGUMENTS: ${{ inputs.linux_nightly_main_arguments_override }}
           MATRIX_WINDOWS_COMMAND: "swift test"
           MATRIX_WINDOWS_ENV_VARS: "TEST_VAR_DEBUG=1,TEST_VAR_LOG_LEVEL=info"  # TODO: remove, testing
+        #   MATRIX_WINDOWS_ENV_VARS: ${{ inputs.windows_env_vars }}
+          MATRIX_WINDOWS_ENV_VAR_PAIR_SEPARATOR: ${{ inputs.windows_env_var_pair_separator }}
+          MATRIX_WINDOWS_ENV_VAR_LIST_SEPARATOR: ${{ inputs.windows_env_var_list_separator }}
           MATRIX_WINDOWS_6_0_ENABLED: ${{ inputs.windows_6_0_enabled }}
           MATRIX_WINDOWS_6_0_COMMAND_ARGUMENTS: ${{ inputs.windows_6_0_arguments_override }}
           MATRIX_WINDOWS_6_1_ENABLED: ${{ inputs.windows_6_1_enabled }}

From df8e205e634a156b6965ffeb1d820f2413ca8d38 Mon Sep 17 00:00:00 2001
From: Rick Newton-Rogers <rnro@apple.com>
Date: Fri, 19 Sep 2025 11:58:24 +0100
Subject: [PATCH 06/27] change windows env var substitution syntax

---
 .github/workflows/swift_test_matrix.yml | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/.github/workflows/swift_test_matrix.yml b/.github/workflows/swift_test_matrix.yml
index e0f49e752b..69f623e49a 100644
--- a/.github/workflows/swift_test_matrix.yml
+++ b/.github/workflows/swift_test_matrix.yml
@@ -78,8 +78,8 @@ jobs:
           $docker_args = @(
               "run", "-v", "${{ github.workspace }}:$($workspace)",
               "-w", $workspace,
-              "-e", "CI=%CI%",
-              "-e", "GITHUB_ACTIONS=%GITHUB_ACTIONS%",
+              "-e", "CI=$env:CI",
+              "-e", "GITHUB_ACTIONS=$env:GITHUB_ACTIONS",
               "-e", "SWIFT_VERSION=${{ matrix.config.swift_version }}"
           )
 

From e50bc6bbc47c2242a14b1dc281d4f93f2dbf9a8e Mon Sep 17 00:00:00 2001
From: Rick Newton-Rogers <rnro@apple.com>
Date: Fri, 19 Sep 2025 14:06:33 +0100
Subject: [PATCH 07/27] merge in 6.2 changes

---
 scripts/generate_matrix.sh | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/scripts/generate_matrix.sh b/scripts/generate_matrix.sh
index abb5f84a06..0472f26e0d 100755
--- a/scripts/generate_matrix.sh
+++ b/scripts/generate_matrix.sh
@@ -179,7 +179,8 @@ if [[ "$linux_6_2_enabled" == "true" ]]; then
     --arg command_arguments "$linux_6_2_command_arguments" \
     --arg container_image "$linux_6_2_container_image" \
     --arg runner "$linux_runner" \
-    '.config[.config| length] |= . + { "name": "6.2", "image": $container_image, "swift_version": "6.2", "platform": "Linux", "command": $command, "command_arguments": $command_arguments, "setup_command": $setup_command, "runner": $runner}')
+    --argjson env_vars "$linux_env_vars_json" \
+    '.config[.config| length] |= . + { "name": "6.2", "image": $container_image, "swift_version": "6.2", "platform": "Linux", "command": $command, "command_arguments": $command_arguments, "setup_command": $setup_command, "runner": $runner, "env": $env_vars}')
 fi
 
 if [[ "$linux_nightly_next_enabled" == "true" ]]; then
@@ -245,7 +246,8 @@ if [[ "$windows_6_2_enabled" == "true" ]]; then
     --arg command_arguments "$windows_6_2_command_arguments" \
     --arg container_image "$windows_6_2_container_image" \
     --arg runner "$windows_6_2_runner" \
-    '.config[.config| length] |= . + { "name": "6.2", "image": $container_image, "swift_version": "6.2", "platform": "Windows", "command": $command, "command_arguments": $command_arguments, "setup_command": $setup_command, "runner": $runner }')
+    --argjson env_vars "$windows_env_vars_json" \
+    '.config[.config| length] |= . + { "name": "6.2", "image": $container_image, "swift_version": "6.2", "platform": "Windows", "command": $command, "command_arguments": $command_arguments, "setup_command": $setup_command, "runner": $runner, "env": $env_vars }')
 fi
 
 if [[ "$windows_nightly_next_enabled" == "true" ]]; then

From b348db692d2b529f7f48bd4f95bfc1e4993eb978 Mon Sep 17 00:00:00 2001
From: Rick Newton-Rogers <rnro@apple.com>
Date: Fri, 19 Sep 2025 10:52:53 +0100
Subject: [PATCH 08/27] test shim

---
 .github/workflows/benchmarks.yml             |  2 +-
 .github/workflows/cxx_interop.yml            |  2 +-
 .github/workflows/main.yml                   | 16 ++++++++--------
 .github/workflows/pull_request.yml           | 16 ++++++++--------
 .github/workflows/release_builds.yml         |  2 +-
 .github/workflows/static_sdk.yml             |  2 +-
 .github/workflows/swift_load_test_matrix.yml |  2 +-
 .github/workflows/unit_tests.yml             |  4 ++--
 8 files changed, 23 insertions(+), 23 deletions(-)

diff --git a/.github/workflows/benchmarks.yml b/.github/workflows/benchmarks.yml
index 0a0d5ae633..4f9efb92ad 100644
--- a/.github/workflows/benchmarks.yml
+++ b/.github/workflows/benchmarks.yml
@@ -127,7 +127,7 @@ jobs:
     name: Benchmarks
     needs: construct-matrix
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@main
+    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@matrix_custom_env_vars
     with:
       name: "Benchmarks"
       matrix_string: '${{ needs.construct-matrix.outputs.benchmarks-matrix }}'
diff --git a/.github/workflows/cxx_interop.yml b/.github/workflows/cxx_interop.yml
index 480df6c958..1076a43408 100644
--- a/.github/workflows/cxx_interop.yml
+++ b/.github/workflows/cxx_interop.yml
@@ -89,7 +89,7 @@ jobs:
     name: Cxx interop
     needs: construct-matrix
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@main
+    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@matrix_custom_env_vars
     with:
       name: "Cxx interop"
       matrix_string: '${{ needs.construct-matrix.outputs.cxx-interop-matrix }}'
diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 5178bcce81..5c9ad3702c 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -10,7 +10,7 @@ jobs:
   unit-tests:
     name: Unit tests
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/unit_tests.yml@main
+    uses: apple/swift-nio/.github/workflows/unit_tests.yml@matrix_custom_env_vars
     with:
       linux_5_10_arguments_override: "-Xswiftc -warnings-as-errors --explicit-target-dependency-import-check error"
       linux_6_0_arguments_override: "-Xswiftc -warnings-as-errors --explicit-target-dependency-import-check error"
@@ -22,12 +22,12 @@ jobs:
   cxx-interop:
     name: Cxx interop
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/cxx_interop.yml@main
+    uses: apple/swift-nio/.github/workflows/cxx_interop.yml@matrix_custom_env_vars
 
   benchmarks:
     name: Benchmarks
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/benchmarks.yml@main
+    uses: apple/swift-nio/.github/workflows/benchmarks.yml@matrix_custom_env_vars
     with:
       benchmark_package_path: "Benchmarks"
 
@@ -51,7 +51,7 @@ jobs:
     name: Integration tests
     needs: construct-integration-test-matrix
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@main
+    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@matrix_custom_env_vars
     with:
       name: "Integration tests"
       matrix_string: '${{ needs.construct-integration-test-matrix.outputs.integration-test-matrix }}'
@@ -59,17 +59,17 @@ jobs:
   static-sdk:
     name: Static Linux Swift SDK
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/static_sdk.yml@main
+    uses: apple/swift-nio/.github/workflows/static_sdk.yml@matrix_custom_env_vars
 
   wasm-sdk:
     name: WebAssembly Swift SDK
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/wasm_sdk.yml@main
+    uses: apple/swift-nio/.github/workflows/wasm_sdk.yml@matrix_custom_env_vars
 
   macos-tests:
     name: macOS tests
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/macos_tests.yml@main
+    uses: apple/swift-nio/.github/workflows/macos_tests.yml@matrix_custom_env_vars
     with:
       runner_pool: nightly
       build_scheme: swift-nio-Package
@@ -83,4 +83,4 @@ jobs:
 
   release-builds:
     name: Release builds
-    uses: apple/swift-nio/.github/workflows/release_builds.yml@main
+    uses: apple/swift-nio/.github/workflows/release_builds.yml@matrix_custom_env_vars
diff --git a/.github/workflows/pull_request.yml b/.github/workflows/pull_request.yml
index f171e1de5b..490ffe2e21 100644
--- a/.github/workflows/pull_request.yml
+++ b/.github/workflows/pull_request.yml
@@ -14,7 +14,7 @@ jobs:
   unit-tests:
     name: Unit tests
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/unit_tests.yml@main
+    uses: apple/swift-nio/.github/workflows/unit_tests.yml@matrix_custom_env_vars
     with:
       linux_5_10_arguments_override: "-Xswiftc -warnings-as-errors --explicit-target-dependency-import-check error"
       linux_6_0_arguments_override: "-Xswiftc -warnings-as-errors --explicit-target-dependency-import-check error"
@@ -26,14 +26,14 @@ jobs:
   benchmarks:
     name: Benchmarks
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/benchmarks.yml@main
+    uses: apple/swift-nio/.github/workflows/benchmarks.yml@matrix_custom_env_vars
     with:
       benchmark_package_path: "Benchmarks"
 
   cxx-interop:
     name: Cxx interop
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/cxx_interop.yml@main
+    uses: apple/swift-nio/.github/workflows/cxx_interop.yml@matrix_custom_env_vars
 
   construct-integration-test-matrix:
     name: Construct integration test matrix
@@ -55,7 +55,7 @@ jobs:
     name: Integration tests
     needs: construct-integration-test-matrix
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@main
+    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@matrix_custom_env_vars
     with:
       name: "Integration tests"
       matrix_string: '${{ needs.construct-integration-test-matrix.outputs.integration-test-matrix }}'
@@ -81,7 +81,7 @@ jobs:
   macos-tests:
     name: macOS tests
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/macos_tests.yml@main
+    uses: apple/swift-nio/.github/workflows/macos_tests.yml@matrix_custom_env_vars
     with:
       runner_pool: general
       build_scheme: swift-nio-Package
@@ -91,13 +91,13 @@ jobs:
   static-sdk:
     name: Static Linux Swift SDK
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/static_sdk.yml@main
+    uses: apple/swift-nio/.github/workflows/static_sdk.yml@matrix_custom_env_vars
 
   wasm-sdk:
     name: WebAssembly Swift SDK
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/wasm_sdk.yml@main
+    uses: apple/swift-nio/.github/workflows/wasm_sdk.yml@matrix_custom_env_vars
 
   release-builds:
     name: Release builds
-    uses: apple/swift-nio/.github/workflows/release_builds.yml@main
+    uses: apple/swift-nio/.github/workflows/release_builds.yml@matrix_custom_env_vars
diff --git a/.github/workflows/release_builds.yml b/.github/workflows/release_builds.yml
index 01079a8b32..1915dd7aac 100644
--- a/.github/workflows/release_builds.yml
+++ b/.github/workflows/release_builds.yml
@@ -137,7 +137,7 @@ jobs:
     name: Release builds
     needs: construct-matrix
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@main
+    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@matrix_custom_env_vars
     with:
       name: "Release builds"
       matrix_string: '${{ needs.construct-matrix.outputs.release-build-matrix }}'
diff --git a/.github/workflows/static_sdk.yml b/.github/workflows/static_sdk.yml
index 6c76b97c0d..c58f353545 100644
--- a/.github/workflows/static_sdk.yml
+++ b/.github/workflows/static_sdk.yml
@@ -7,7 +7,7 @@ jobs:
   static-sdk:
     name: Static SDK
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@main
+    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@matrix_custom_env_vars
     with:
       name: "Static SDK"
       matrix_string: >-
diff --git a/.github/workflows/swift_load_test_matrix.yml b/.github/workflows/swift_load_test_matrix.yml
index 9b7b53b7f2..12b2df5c12 100644
--- a/.github/workflows/swift_load_test_matrix.yml
+++ b/.github/workflows/swift_load_test_matrix.yml
@@ -35,7 +35,7 @@ jobs:
     name: Execute matrix
     needs: load-matrix
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@main
+    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@matrix_custom_env_vars
     with:
       name: ${{ inputs.name }}
       matrix_string: '${{ needs.load-matrix.outputs.swift-matrix }}'
diff --git a/.github/workflows/unit_tests.yml b/.github/workflows/unit_tests.yml
index 4ef6723900..53f09376e3 100644
--- a/.github/workflows/unit_tests.yml
+++ b/.github/workflows/unit_tests.yml
@@ -170,7 +170,7 @@ jobs:
         with:
           persist-credentials: false
       - id: generate-matrix
-        run: echo "unit-test-matrix=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/generate_matrix.sh | bash)" >> "$GITHUB_OUTPUT"
+        run: echo "unit-test-matrix=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/matrix_custom_env_vars/scripts/generate_matrix.sh | bash)" >> "$GITHUB_OUTPUT"
         env:
           MATRIX_LINUX_SETUP_COMMAND: "swift --version"
           MATRIX_LINUX_COMMAND: "swift test"
@@ -212,7 +212,7 @@ jobs:
     name: Unit tests
     needs: construct-matrix
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@main
+    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@matrix_custom_env_vars
     with:
       name: "Unit tests"
       matrix_string: '${{ needs.construct-matrix.outputs.unit-test-matrix }}'

From 0c7b341181c906777a62b8efd7d513b542853fe7 Mon Sep 17 00:00:00 2001
From: Rick Newton-Rogers <rnro@apple.com>
Date: Fri, 19 Sep 2025 14:49:35 +0100
Subject: [PATCH 09/27] Revert "test env vars"

This reverts commit 4d0ffd6577b12a5290a209ab990b65f72b729728.
---
 .github/workflows/unit_tests.yml | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/.github/workflows/unit_tests.yml b/.github/workflows/unit_tests.yml
index 53f09376e3..f397e0187f 100644
--- a/.github/workflows/unit_tests.yml
+++ b/.github/workflows/unit_tests.yml
@@ -174,8 +174,7 @@ jobs:
         env:
           MATRIX_LINUX_SETUP_COMMAND: "swift --version"
           MATRIX_LINUX_COMMAND: "swift test"
-          MATRIX_LINUX_ENV_VARS: "TEST_VAR_DEBUG=1,TEST_VAR_LOG_LEVEL=info"  # TODO: remove, testing
-        #   MATRIX_LINUX_ENV_VARS: ${{ inputs.linux_env_vars }}
+          MATRIX_LINUX_ENV_VARS: ${{ inputs.linux_env_vars }}
           MATRIX_LINUX_ENV_VAR_PAIR_SEPARATOR: ${{ inputs.linux_env_var_pair_separator }}
           MATRIX_LINUX_ENV_VAR_LIST_SEPARATOR: ${{ inputs.linux_env_var_list_separator }}
           MATRIX_LINUX_5_9_ENABLED: ${{ inputs.linux_5_9_enabled }}
@@ -193,8 +192,7 @@ jobs:
           MATRIX_LINUX_NIGHTLY_MAIN_ENABLED: ${{ inputs.linux_nightly_main_enabled }}
           MATRIX_LINUX_NIGHTLY_MAIN_COMMAND_ARGUMENTS: ${{ inputs.linux_nightly_main_arguments_override }}
           MATRIX_WINDOWS_COMMAND: "swift test"
-          MATRIX_WINDOWS_ENV_VARS: "TEST_VAR_DEBUG=1,TEST_VAR_LOG_LEVEL=info"  # TODO: remove, testing
-        #   MATRIX_WINDOWS_ENV_VARS: ${{ inputs.windows_env_vars }}
+          MATRIX_WINDOWS_ENV_VARS: ${{ inputs.windows_env_vars }}
           MATRIX_WINDOWS_ENV_VAR_PAIR_SEPARATOR: ${{ inputs.windows_env_var_pair_separator }}
           MATRIX_WINDOWS_ENV_VAR_LIST_SEPARATOR: ${{ inputs.windows_env_var_list_separator }}
           MATRIX_WINDOWS_6_0_ENABLED: ${{ inputs.windows_6_0_enabled }}

From 3ab2ae171c1fbb85dc862b5f5f5fe06848e7e6ee Mon Sep 17 00:00:00 2001
From: Rick Newton-Rogers <rnro@apple.com>
Date: Fri, 19 Sep 2025 15:10:26 +0100
Subject: [PATCH 10/27] adopt in release builds and C++

---
 .github/workflows/benchmarks.yml     | 15 --------------
 .github/workflows/cxx_interop.yml    | 31 ++++++++++++++++++++++++++++
 .github/workflows/release_builds.yml | 31 ++++++++++++++++++++++++++++
 3 files changed, 62 insertions(+), 15 deletions(-)

diff --git a/.github/workflows/benchmarks.yml b/.github/workflows/benchmarks.yml
index 4f9efb92ad..22a5844387 100644
--- a/.github/workflows/benchmarks.yml
+++ b/.github/workflows/benchmarks.yml
@@ -80,18 +80,6 @@ on:
         type: string
         description: "Separator between environment variable pairs for Linux."
         default: ","
-      windows_env_vars:
-        type: string
-        description: "Environment variables for Windows jobs (e.g., 'DEBUG=1,LOG_LEVEL=info')."
-        default: ""
-      windows_env_var_pair_separator:
-        type: string
-        description: "Separator between key and value for Windows environment variables."
-        default: "="
-      windows_env_var_list_separator:
-        type: string
-        description: "Separator between environment variable pairs for Windows."
-        default: ","
 
 jobs:
   construct-matrix:
@@ -119,9 +107,6 @@ jobs:
           MATRIX_LINUX_6_2_ENABLED: ${{ inputs.linux_6_2_enabled }}
           MATRIX_LINUX_NIGHTLY_NEXT_ENABLED: ${{ inputs.linux_nightly_6_1_enabled && inputs.linux_nightly_next_enabled  }}
           MATRIX_LINUX_NIGHTLY_MAIN_ENABLED: ${{ inputs.linux_nightly_main_enabled }}
-          MATRIX_WINDOWS_ENV_VARS: ${{ inputs.windows_env_vars }}
-          MATRIX_WINDOWS_ENV_VAR_PAIR_SEPARATOR: ${{ inputs.windows_env_var_pair_separator }}
-          MATRIX_WINDOWS_ENV_VAR_LIST_SEPARATOR: ${{ inputs.windows_env_var_list_separator }}
 
   benchmarks:
     name: Benchmarks
diff --git a/.github/workflows/cxx_interop.yml b/.github/workflows/cxx_interop.yml
index 1076a43408..d0ba3f3182 100644
--- a/.github/workflows/cxx_interop.yml
+++ b/.github/workflows/cxx_interop.yml
@@ -61,6 +61,31 @@ on:
         description: "Boolean to enable the Windows nightly main Swift version matrix job. Defaults to false. Currently has no effect!"  # TODO: implement Windows Cxx compat checking
         default: false
 
+      linux_env_vars:
+        type: string
+        description: "Environment variables for Linux jobs (e.g., 'DEBUG=1,LOG_LEVEL=info')."
+        default: ""
+      linux_env_var_pair_separator:
+        type: string
+        description: "Separator between key and value for Linux environment variables."
+        default: "="
+      linux_env_var_list_separator:
+        type: string
+        description: "Separator between environment variable pairs for Linux."
+        default: ","
+      windows_env_vars:
+        type: string
+        description: "Environment variables for Windows jobs (e.g., 'DEBUG=1,LOG_LEVEL=info')."
+        default: ""
+      windows_env_var_pair_separator:
+        type: string
+        description: "Separator between key and value for Windows environment variables."
+        default: "="
+      windows_env_var_list_separator:
+        type: string
+        description: "Separator between environment variable pairs for Windows."
+        default: ","
+
 jobs:
   construct-matrix:
     name: Construct Cxx interop matrix
@@ -77,6 +102,9 @@ jobs:
         env:
           MATRIX_LINUX_COMMAND: "curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/check-cxx-interop-compatibility.sh | bash"
           MATRIX_LINUX_SETUP_COMMAND: "swift --version && apt-get update -y -q && apt-get install -y -q curl jq"
+          MATRIX_LINUX_ENV_VARS: ${{ inputs.linux_env_vars }}
+          MATRIX_LINUX_ENV_VAR_PAIR_SEPARATOR: ${{ inputs.linux_env_var_pair_separator }}
+          MATRIX_LINUX_ENV_VAR_LIST_SEPARATOR: ${{ inputs.linux_env_var_list_separator }}
           MATRIX_LINUX_5_9_ENABLED: ${{ inputs.linux_5_9_enabled }}
           MATRIX_LINUX_5_10_ENABLED: ${{ inputs.linux_5_10_enabled }}
           MATRIX_LINUX_6_0_ENABLED: ${{ inputs.linux_6_0_enabled }}
@@ -84,6 +112,9 @@ jobs:
           MATRIX_LINUX_6_2_ENABLED: ${{ inputs.linux_6_2_enabled }}
           MATRIX_LINUX_NIGHTLY_NEXT_ENABLED: ${{ inputs.linux_nightly_6_1_enabled && inputs.linux_nightly_next_enabled }}
           MATRIX_LINUX_NIGHTLY_MAIN_ENABLED: ${{ inputs.linux_nightly_main_enabled }}
+          MATRIX_WINDOWS_ENV_VARS: ${{ inputs.windows_env_vars }}
+          MATRIX_WINDOWS_ENV_VAR_PAIR_SEPARATOR: ${{ inputs.windows_env_var_pair_separator }}
+          MATRIX_WINDOWS_ENV_VAR_LIST_SEPARATOR: ${{ inputs.windows_env_var_list_separator }}
 
   cxx-interop:
     name: Cxx interop
diff --git a/.github/workflows/release_builds.yml b/.github/workflows/release_builds.yml
index 1915dd7aac..3fbfbe6f98 100644
--- a/.github/workflows/release_builds.yml
+++ b/.github/workflows/release_builds.yml
@@ -93,6 +93,31 @@ on:
         description: "The arguments passed to swift test in the Windows nightly main Swift version matrix job."
         default: ""
 
+      linux_env_vars:
+        type: string
+        description: "Environment variables for Linux jobs (e.g., 'DEBUG=1,LOG_LEVEL=info')."
+        default: ""
+      linux_env_var_pair_separator:
+        type: string
+        description: "Separator between key and value for Linux environment variables."
+        default: "="
+      linux_env_var_list_separator:
+        type: string
+        description: "Separator between environment variable pairs for Linux."
+        default: ","
+      windows_env_vars:
+        type: string
+        description: "Environment variables for Windows jobs (e.g., 'DEBUG=1,LOG_LEVEL=info')."
+        default: ""
+      windows_env_var_pair_separator:
+        type: string
+        description: "Separator between key and value for Windows environment variables."
+        default: "="
+      windows_env_var_list_separator:
+        type: string
+        description: "Separator between environment variable pairs for Windows."
+        default: ","
+
 jobs:
   construct-matrix:
     name: Construct release build matrix
@@ -109,6 +134,9 @@ jobs:
         env:
           MATRIX_LINUX_SETUP_COMMAND: "swift --version"
           MATRIX_LINUX_COMMAND: "swift build -c release"
+          MATRIX_LINUX_ENV_VARS: ${{ inputs.linux_env_vars }}
+          MATRIX_LINUX_ENV_VAR_PAIR_SEPARATOR: ${{ inputs.linux_env_var_pair_separator }}
+          MATRIX_LINUX_ENV_VAR_LIST_SEPARATOR: ${{ inputs.linux_env_var_list_separator }}
           MATRIX_LINUX_5_10_ENABLED: ${{ inputs.linux_5_10_enabled }}
           MATRIX_LINUX_5_10_COMMAND_ARGUMENTS: ${{ inputs.linux_5_10_arguments_override }}
           MATRIX_LINUX_6_0_ENABLED: ${{ inputs.linux_6_0_enabled }}
@@ -132,6 +160,9 @@ jobs:
           MATRIX_WINDOWS_NIGHTLY_NEXT_COMMAND_ARGUMENTS: ${{ inputs.windows_nightly_next_arguments_override }}
           MATRIX_WINDOWS_NIGHTLY_MAIN_ENABLED: ${{ inputs.windows_nightly_main_enabled }}
           MATRIX_WINDOWS_NIGHTLY_MAIN_COMMAND_ARGUMENTS: ${{ inputs.windows_nightly_main_arguments_override }}
+          MATRIX_WINDOWS_ENV_VARS: ${{ inputs.windows_env_vars }}
+          MATRIX_WINDOWS_ENV_VAR_PAIR_SEPARATOR: ${{ inputs.windows_env_var_pair_separator }}
+          MATRIX_WINDOWS_ENV_VAR_LIST_SEPARATOR: ${{ inputs.windows_env_var_list_separator }}
 
   release-builds:
     name: Release builds

From 9c8a04b39bce7b1b7c8e5a9abaa76a5656880e7d Mon Sep 17 00:00:00 2001
From: Rick Newton-Rogers <rnro@apple.com>
Date: Fri, 19 Sep 2025 16:14:05 +0100
Subject: [PATCH 11/27] split out parse_env_vars, use on macos, static SDK

---
 .github/workflows/macos_tests.yml | 43 ++++++++++++---
 .github/workflows/static_sdk.yml  | 91 ++++++++++++++++++++++---------
 .github/workflows/unit_tests.yml  | 16 +++---
 scripts/generate_matrix.sh        | 46 +---------------
 scripts/parse_env_vars.sh         | 50 +++++++++++++++++
 5 files changed, 161 insertions(+), 85 deletions(-)
 create mode 100644 scripts/parse_env_vars.sh

diff --git a/.github/workflows/macos_tests.yml b/.github/workflows/macos_tests.yml
index 482a0f4b12..f26b2ac0b0 100644
--- a/.github/workflows/macos_tests.yml
+++ b/.github/workflows/macos_tests.yml
@@ -193,6 +193,19 @@ on:
         description: "The runner pool which will be requested."
         default: "nightly"
 
+      env_vars:
+        type: string
+        description: "Environment variables for jobs (e.g., 'DEBUG=1,LOG_LEVEL=info')."
+        default: ""
+      env_var_pair_separator:
+        type: string
+        description: "Separator between key and value for environment variables."
+        default: "="
+      env_var_list_separator:
+        type: string
+        description: "Separator between environment variable pairs."
+        default: ","
+
 jobs:
   construct-matrix:
     name: Construct Darwin matrix
@@ -206,6 +219,9 @@ jobs:
           persist-credentials: false
       - id: generate-matrix
         run: |
+          # Parse environment variables using the parse_env_vars script
+          env_vars_json=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/parse_env_vars.sh | ENV_VARS="$MATRIX_ENV_VARS" ENV_VAR_PAIR_SEPARATOR="$MATRIX_ENV_VAR_PAIR_SEPARATOR" ENV_VAR_LIST_SEPARATOR="$MATRIX_ENV_VAR_LIST_SEPARATOR" bash)
+
           cat >> "$GITHUB_OUTPUT" << EOM
           darwin-matrix=$(
             runner_pool="${MATRIX_RUNNER_POOL:="nightly"}"
@@ -255,7 +271,8 @@ jobs:
                 --arg build_arguments_override "$xcode_15_4_build_arguments_override"  \
                 --arg test_arguments_override "$xcode_15_4_test_arguments_override"  \
                 --arg runner_pool "$runner_pool"  \
-                '.config[.config| length] |= . + { "name": "Xcode 15.4", "xcode_version": "15.4", "xcode_app": "Xcode_15.4.app", "setup_command": $setup_command, "build_arguments_override": $build_arguments_override, "test_arguments_override": $test_arguments_override, "os": "sequoia", "arch": "ARM64", "pool": $runner_pool }')
+                --argjson env_vars "$env_vars_json" \
+                '.config[.config| length] |= . + { "name": "Xcode 15.4", "xcode_version": "15.4", "xcode_app": "Xcode_15.4.app", "setup_command": $setup_command, "build_arguments_override": $build_arguments_override, "test_arguments_override": $test_arguments_override, "os": "sequoia", "arch": "ARM64", "pool": $runner_pool, "env": $env_vars }')
             fi
 
             if [[ "$xcode_16_0_enabled" == "true" ]]; then
@@ -264,7 +281,8 @@ jobs:
                 --arg build_arguments_override "$xcode_16_0_build_arguments_override"  \
                 --arg test_arguments_override "$xcode_16_0_test_arguments_override"  \
                 --arg runner_pool "$runner_pool"  \
-                '.config[.config| length] |= . + { "name": "Xcode 16.0", "xcode_version": "16.0", "xcode_app": "Xcode_16.0.app", "setup_command": $setup_command, "build_arguments_override": $build_arguments_override, "test_arguments_override": $test_arguments_override, "os": "sequoia", "arch": "ARM64", "pool": $runner_pool }')
+                --argjson env_vars "$env_vars_json" \
+                '.config[.config| length] |= . + { "name": "Xcode 16.0", "xcode_version": "16.0", "xcode_app": "Xcode_16.0.app", "setup_command": $setup_command, "build_arguments_override": $build_arguments_override, "test_arguments_override": $test_arguments_override, "os": "sequoia", "arch": "ARM64", "pool": $runner_pool, "env": $env_vars }')
             fi
 
             if [[ "$xcode_16_1_enabled" == "true" ]]; then
@@ -273,7 +291,8 @@ jobs:
                 --arg build_arguments_override "$xcode_16_1_build_arguments_override"  \
                 --arg test_arguments_override "$xcode_16_1_test_arguments_override"  \
                 --arg runner_pool "$runner_pool"  \
-                '.config[.config| length] |= . + { "name": "Xcode 16.1", "xcode_version": "16.1", "xcode_app": "Xcode_16.1.app", "setup_command": $setup_command, "build_arguments_override": $build_arguments_override, "test_arguments_override": $test_arguments_override, "os": "sequoia", "arch": "ARM64", "pool": $runner_pool }')
+                --argjson env_vars "$env_vars_json" \
+                '.config[.config| length] |= . + { "name": "Xcode 16.1", "xcode_version": "16.1", "xcode_app": "Xcode_16.1.app", "setup_command": $setup_command, "build_arguments_override": $build_arguments_override, "test_arguments_override": $test_arguments_override, "os": "sequoia", "arch": "ARM64", "pool": $runner_pool, "env": $env_vars }')
             fi
 
             if [[ "$xcode_16_2_enabled" == "true" ]]; then
@@ -282,7 +301,8 @@ jobs:
                 --arg build_arguments_override "$xcode_16_2_build_arguments_override"  \
                 --arg test_arguments_override "$xcode_16_2_test_arguments_override"  \
                 --arg runner_pool "$runner_pool"  \
-                '.config[.config| length] |= . + { "name": "Xcode 16.2", "xcode_version": "16.2", "xcode_app": "Xcode_16.2.app", "setup_command": $setup_command, "build_arguments_override": $build_arguments_override, "test_arguments_override": $test_arguments_override, "os": "sequoia", "arch": "ARM64", "pool": $runner_pool }')
+                --argjson env_vars "$env_vars_json" \
+                '.config[.config| length] |= . + { "name": "Xcode 16.2", "xcode_version": "16.2", "xcode_app": "Xcode_16.2.app", "setup_command": $setup_command, "build_arguments_override": $build_arguments_override, "test_arguments_override": $test_arguments_override, "os": "sequoia", "arch": "ARM64", "pool": $runner_pool, "env": $env_vars }')
             fi
 
             if [[ "$xcode_16_3_enabled" == "true" ]]; then
@@ -291,7 +311,8 @@ jobs:
                 --arg build_arguments_override "$xcode_16_3_build_arguments_override"  \
                 --arg test_arguments_override "$xcode_16_3_test_arguments_override"  \
                 --arg runner_pool "$runner_pool"  \
-                '.config[.config| length] |= . + { "name": "Xcode 16.3", "xcode_version": "16.3", "xcode_app": "Xcode_16.3.app", "setup_command": $setup_command, "build_arguments_override": $build_arguments_override, "test_arguments_override": $test_arguments_override, "os": "sequoia", "arch": "ARM64", "pool": $runner_pool }')
+                --argjson env_vars "$env_vars_json" \
+                '.config[.config| length] |= . + { "name": "Xcode 16.3", "xcode_version": "16.3", "xcode_app": "Xcode_16.3.app", "setup_command": $setup_command, "build_arguments_override": $build_arguments_override, "test_arguments_override": $test_arguments_override, "os": "sequoia", "arch": "ARM64", "pool": $runner_pool, "env": $env_vars }')
             fi
 
             if [[ "$xcode_16_4_enabled" == "true" ]]; then
@@ -300,7 +321,8 @@ jobs:
                 --arg build_arguments_override "$xcode_16_4_build_arguments_override"  \
                 --arg test_arguments_override "$xcode_16_4_test_arguments_override"  \
                 --arg runner_pool "$runner_pool"  \
-                '.config[.config| length] |= . + { "name": "Xcode 16.4", "xcode_version": "16.4", "xcode_app": "Xcode_16.4.app", "setup_command": $setup_command, "build_arguments_override": $build_arguments_override, "test_arguments_override": $test_arguments_override, "os": "sequoia", "arch": "ARM64", "pool": $runner_pool }')
+                --argjson env_vars "$env_vars_json" \
+                '.config[.config| length] |= . + { "name": "Xcode 16.4", "xcode_version": "16.4", "xcode_app": "Xcode_16.4.app", "setup_command": $setup_command, "build_arguments_override": $build_arguments_override, "test_arguments_override": $test_arguments_override, "os": "sequoia", "arch": "ARM64", "pool": $runner_pool, "env": $env_vars }')
             fi
 
             if [[ "$xcode_26_0_enabled" == "true" ]]; then
@@ -309,7 +331,8 @@ jobs:
                 --arg build_arguments_override "$xcode_26_0_build_arguments_override"  \
                 --arg test_arguments_override "$xcode_26_0_test_arguments_override"  \
                 --arg runner_pool "$runner_pool"  \
-                '.config[.config| length] |= . + { "name": "Xcode 26.0", "xcode_version": "26.0", "xcode_app": "Xcode_26.0.app", "setup_command": $setup_command, "build_arguments_override": $build_arguments_override, "test_arguments_override": $test_arguments_override, "os": "sequoia", "arch": "ARM64", "pool": $runner_pool }')
+                --argjson env_vars "$env_vars_json" \
+                '.config[.config| length] |= . + { "name": "Xcode 26.0", "xcode_version": "26.0", "xcode_app": "Xcode_26.0.app", "setup_command": $setup_command, "build_arguments_override": $build_arguments_override, "test_arguments_override": $test_arguments_override, "os": "sequoia", "arch": "ARM64", "pool": $runner_pool, "env": $env_vars }')
             fi
 
             if [[ "$xcode_latest_beta_enabled" == "true" ]]; then
@@ -318,13 +341,17 @@ jobs:
                 --arg build_arguments_override "$xcode_latest_beta_build_arguments_override"  \
                 --arg test_arguments_override "$xcode_latest_beta_test_arguments_override"  \
                 --arg runner_pool "$runner_pool"  \
-                '.config[.config| length] |= . + { "name": "Xcode latest beta", "xcode_version": "latest beta", "xcode_app": "Xcode-latest.app", "setup_command": $setup_command, "build_arguments_override": $build_arguments_override, "test_arguments_override": $test_arguments_override, "os": "sequoia", "arch": "ARM64", "pool": $runner_pool }')
+                --argjson env_vars "$env_vars_json" \
+                '.config[.config| length] |= . + { "name": "Xcode latest beta", "xcode_version": "latest beta", "xcode_app": "Xcode-latest.app", "setup_command": $setup_command, "build_arguments_override": $build_arguments_override, "test_arguments_override": $test_arguments_override, "os": "sequoia", "arch": "ARM64", "pool": $runner_pool, "env": $env_vars }')
             fi
 
             echo "$matrix" | jq -c
           )"
           EOM
         env:
+          MATRIX_ENV_VARS: ${{ inputs.env_vars }}
+          MATRIX_ENV_VAR_PAIR_SEPARATOR: ${{ inputs.env_var_pair_separator }}
+          MATRIX_ENV_VAR_LIST_SEPARATOR: ${{ inputs.env_var_list_separator }}
           MATRIX_RUNNER_POOL: ${{ inputs.runner_pool }}
           MATRIX_MACOS_15_4_ENABLED: ${{ inputs.xcode_15_4_enabled }}
           MATRIX_MACOS_15_4_BUILD_ARGUMENTS_OVERRIDE: ${{ inputs.xcode_15_4_build_arguments_override }}
diff --git a/.github/workflows/static_sdk.yml b/.github/workflows/static_sdk.yml
index c58f353545..d172936b5b 100644
--- a/.github/workflows/static_sdk.yml
+++ b/.github/workflows/static_sdk.yml
@@ -2,38 +2,75 @@ name: Static SDK
 
 on:
   workflow_call:
+    inputs:
+      env_vars:
+        type: string
+        description: "Environment variables for jobs (e.g., 'DEBUG=1,LOG_LEVEL=info')."
+        default: ""
+      env_var_pair_separator:
+        type: string
+        description: "Separator between key and value for environment variables."
+        default: "="
+      env_var_list_separator:
+        type: string
+        description: "Separator between environment variable pairs."
+        default: ","
 
 jobs:
+  construct-matrix:
+    name: Construct Static SDK matrix
+    runs-on: ubuntu-latest
+    outputs:
+      static-sdk-matrix: '${{ steps.generate-matrix.outputs.static-sdk-matrix }}'
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+        with:
+          persist-credentials: false
+      - id: generate-matrix
+        run: |
+          # Parse environment variables using the parse_env_vars script
+          env_vars_json=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/parse_env_vars.sh | ENV_VARS="$MATRIX_ENV_VARS" ENV_VAR_PAIR_SEPARATOR="$MATRIX_ENV_VAR_PAIR_SEPARATOR" ENV_VAR_LIST_SEPARATOR="$MATRIX_ENV_VAR_LIST_SEPARATOR" bash)
+
+          # Generate matrix with parsed environment variables
+          cat >> "$GITHUB_OUTPUT" << EOM
+          static-sdk-matrix=$(echo '{
+            "config":[
+              {
+                "name":"latest-release Jammy",
+                "swift_version":"latest-release",
+                "platform":"Linux",
+                "runner":"ubuntu-latest",
+                "image":"ubuntu:jammy",
+                "setup_command":"apt update -q && apt install -y -q curl jq tar && curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/install_swift_prerequisites.sh | bash && curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/install_static_sdk.sh | INSTALL_SWIFT_STATIC_SDK_VERSION=latest INSTALL_SWIFT_STATIC_SDK_ARCH=x86_64 bash && hash -r",
+                "command":"swift build",
+                "command_arguments":"--swift-sdk x86_64-swift-linux-musl",
+                "env":'"$env_vars_json"'
+              },
+              {
+                "name":"main Jammy",
+                "swift_version":"main",
+                "platform":"Linux",
+                "runner":"ubuntu-latest",
+                "image":"ubuntu:jammy",
+                "setup_command":"apt update -q && apt install -y -q curl jq tar && curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/install_swift_prerequisites.sh | bash && curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/install_static_sdk.sh | INSTALL_SWIFT_STATIC_SDK_BRANCH=main INSTALL_SWIFT_STATIC_SDK_ARCH=x86_64 bash && hash -r",
+                "command":"swift build",
+                "command_arguments":"--swift-sdk x86_64-swift-linux-musl",
+                "env":'"$env_vars_json"'
+              }
+            ]
+          }' | jq -c)
+          EOM
+        env:
+          MATRIX_ENV_VARS: ${{ inputs.env_vars }}
+          MATRIX_ENV_VAR_PAIR_SEPARATOR: ${{ inputs.env_var_pair_separator }}
+          MATRIX_ENV_VAR_LIST_SEPARATOR: ${{ inputs.env_var_list_separator }}
+
   static-sdk:
     name: Static SDK
+    needs: construct-matrix
     # Workaround https://github.com/nektos/act/issues/1875
     uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@matrix_custom_env_vars
     with:
       name: "Static SDK"
-      matrix_string: >-
-        {
-          "config":[
-            {
-              "name":"latest-release Jammy",
-              "swift_version":"latest-release",
-              "platform":"Linux",
-              "runner":"ubuntu-latest",
-              "image":"ubuntu:jammy",
-              "setup_command":"apt update -q && apt install -y -q curl jq tar && curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/install_swift_prerequisites.sh | bash && curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/install_static_sdk.sh | INSTALL_SWIFT_STATIC_SDK_VERSION=latest INSTALL_SWIFT_STATIC_SDK_ARCH=x86_64 bash && hash -r",
-              "command":"swift build",
-              "command_arguments":"--swift-sdk x86_64-swift-linux-musl",
-              "env":{}
-            },
-            {
-              "name":"main Jammy",
-              "swift_version":"main",
-              "platform":"Linux",
-              "runner":"ubuntu-latest",
-              "image":"ubuntu:jammy",
-              "setup_command":"apt update -q && apt install -y -q curl jq tar && curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/install_swift_prerequisites.sh | bash && curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/install_static_sdk.sh | INSTALL_SWIFT_STATIC_SDK_BRANCH=main INSTALL_SWIFT_STATIC_SDK_ARCH=x86_64 bash && hash -r",
-              "command":"swift build",
-              "command_arguments":"--swift-sdk x86_64-swift-linux-musl",
-              "env":{}
-            }
-          ]
-        }
+      matrix_string: '${{ needs.construct-matrix.outputs.static-sdk-matrix }}'
diff --git a/.github/workflows/unit_tests.yml b/.github/workflows/unit_tests.yml
index f397e0187f..70854c8984 100644
--- a/.github/workflows/unit_tests.yml
+++ b/.github/workflows/unit_tests.yml
@@ -170,13 +170,18 @@ jobs:
         with:
           persist-credentials: false
       - id: generate-matrix
-        run: echo "unit-test-matrix=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/matrix_custom_env_vars/scripts/generate_matrix.sh | bash)" >> "$GITHUB_OUTPUT"
+        run: |
+          # Parse Linux environment variables
+          linux_env_vars_json=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/parse_env_vars.sh | ENV_VARS="${{ inputs.linux_env_vars }}" ENV_VAR_PAIR_SEPARATOR="${{ inputs.linux_env_var_pair_separator }}" ENV_VAR_LIST_SEPARATOR="${{ inputs.linux_env_var_list_separator }}" bash)
+
+          # Parse Windows environment variables
+          windows_env_vars_json=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/parse_env_vars.sh | ENV_VARS="${{ inputs.windows_env_vars }}" ENV_VAR_PAIR_SEPARATOR="${{ inputs.windows_env_var_pair_separator }}" ENV_VAR_LIST_SEPARATOR="${{ inputs.windows_env_var_list_separator }}" bash)
+
+          # Generate matrix
+          echo "unit-test-matrix=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/matrix_custom_env_vars/scripts/generate_matrix.sh | MATRIX_LINUX_ENV_VARS_JSON="${linux_env_vars_json}" MATRIX_WINDOWS_ENV_VARS_JSON="${windows_env_vars_json}" bash)" >> "$GITHUB_OUTPUT"
         env:
           MATRIX_LINUX_SETUP_COMMAND: "swift --version"
           MATRIX_LINUX_COMMAND: "swift test"
-          MATRIX_LINUX_ENV_VARS: ${{ inputs.linux_env_vars }}
-          MATRIX_LINUX_ENV_VAR_PAIR_SEPARATOR: ${{ inputs.linux_env_var_pair_separator }}
-          MATRIX_LINUX_ENV_VAR_LIST_SEPARATOR: ${{ inputs.linux_env_var_list_separator }}
           MATRIX_LINUX_5_9_ENABLED: ${{ inputs.linux_5_9_enabled }}
           MATRIX_LINUX_5_9_COMMAND_ARGUMENTS: ${{ inputs.linux_5_9_arguments_override }}
           MATRIX_LINUX_5_10_ENABLED: ${{ inputs.linux_5_10_enabled }}
@@ -192,9 +197,6 @@ jobs:
           MATRIX_LINUX_NIGHTLY_MAIN_ENABLED: ${{ inputs.linux_nightly_main_enabled }}
           MATRIX_LINUX_NIGHTLY_MAIN_COMMAND_ARGUMENTS: ${{ inputs.linux_nightly_main_arguments_override }}
           MATRIX_WINDOWS_COMMAND: "swift test"
-          MATRIX_WINDOWS_ENV_VARS: ${{ inputs.windows_env_vars }}
-          MATRIX_WINDOWS_ENV_VAR_PAIR_SEPARATOR: ${{ inputs.windows_env_var_pair_separator }}
-          MATRIX_WINDOWS_ENV_VAR_LIST_SEPARATOR: ${{ inputs.windows_env_var_list_separator }}
           MATRIX_WINDOWS_6_0_ENABLED: ${{ inputs.windows_6_0_enabled }}
           MATRIX_WINDOWS_6_0_COMMAND_ARGUMENTS: ${{ inputs.windows_6_0_arguments_override }}
           MATRIX_WINDOWS_6_1_ENABLED: ${{ inputs.windows_6_1_enabled }}
diff --git a/scripts/generate_matrix.sh b/scripts/generate_matrix.sh
index 0472f26e0d..bef41e3b7e 100755
--- a/scripts/generate_matrix.sh
+++ b/scripts/generate_matrix.sh
@@ -16,9 +16,6 @@
 # Parameters
 linux_command="$MATRIX_LINUX_COMMAND"  # required if any Linux pipeline is enabled
 linux_setup_command="$MATRIX_LINUX_SETUP_COMMAND"
-linux_env_vars="$MATRIX_LINUX_ENV_VARS"
-linux_env_var_pair_separator="${MATRIX_LINUX_ENV_VAR_PAIR_SEPARATOR:="="}"
-linux_env_var_list_separator="${MATRIX_LINUX_ENV_VAR_LIST_SEPARATOR:=","}"
 linux_5_9_enabled="${MATRIX_LINUX_5_9_ENABLED:=false}"
 linux_5_9_command_arguments="$MATRIX_LINUX_5_9_COMMAND_ARGUMENTS"
 linux_5_10_enabled="${MATRIX_LINUX_5_10_ENABLED:=true}"
@@ -36,9 +33,6 @@ linux_nightly_main_command_arguments="$MATRIX_LINUX_NIGHTLY_MAIN_COMMAND_ARGUMEN
 
 windows_command="$MATRIX_WINDOWS_COMMAND"  # required if any Windows pipeline is enabled
 windows_setup_command="$MATRIX_WINDOWS_SETUP_COMMAND"
-windows_env_vars="$MATRIX_WINDOWS_ENV_VARS"
-windows_env_var_pair_separator="${MATRIX_WINDOWS_ENV_VAR_PAIR_SEPARATOR:="="}"
-windows_env_var_list_separator="${MATRIX_WINDOWS_ENV_VAR_LIST_SEPARATOR:=","}"
 windows_6_0_enabled="${MATRIX_WINDOWS_6_0_ENABLED:=false}"
 windows_6_1_enabled="${MATRIX_WINDOWS_6_1_ENABLED:=false}"
 windows_6_2_enabled="${MATRIX_WINDOWS_6_2_ENABLED:=false}"
@@ -50,10 +44,6 @@ windows_nightly_next_command_arguments="${MATRIX_WINDOWS_NIGHTLY_NEXT_COMMAND_AR
 windows_nightly_main_enabled="${MATRIX_WINDOWS_NIGHTLY_MAIN_ENABLED:=false}"
 windows_nightly_main_command_arguments="$MATRIX_WINDOWS_NIGHTLY_MAIN_COMMAND_ARGUMENTS"
 
-# Specifying custom environment variables example:
-#   MATRIX_WINDOWS_ENV_VARS="BUILD:Release;ARCH:x64" MATRIX_WINDOWS_ENV_VAR_PAIR_SEPARATOR=":" MATRIX_WINDOWS_ENV_VAR_LIST_SEPARATOR=";" ./generate_matrix.sh
-
-
 # Defaults
 linux_runner="ubuntu-latest"
 linux_5_9_container_image="swift:5.9-jammy"
@@ -75,39 +65,9 @@ windows_nightly_next_container_image="swiftlang/swift:nightly-6.2-windowsserverc
 windows_nightly_main_runner="windows-2022"
 windows_nightly_main_container_image="swiftlang/swift:nightly-main-windowsservercore-ltsc2022"
 
-# Function to parse environment variables and convert to JSON object
-parse_env_vars() {
-  local env_vars="$1"
-  local pair_separator="$2"
-  local list_separator="$3"
-
-  if [[ -z "$env_vars" ]]; then
-    echo "{}"
-    return
-  fi
-
-  local json_obj="{}"
-
-  # Split the env_vars string by list_separator
-  IFS="$list_separator" read -ra env_pairs <<< "$env_vars"
-
-  for pair in "${env_pairs[@]}"; do
-    # Split each pair by pair_separator
-    IFS="$pair_separator" read -ra kv <<< "$pair"
-    if [[ ${#kv[@]} -eq 2 ]]; then
-      local key="${kv[0]}"
-      local value="${kv[1]}"
-      # Add to JSON object using jq
-      json_obj=$(echo "$json_obj" | jq -c --arg key "$key" --arg value "$value" '. + {($key): $value}')
-    fi
-  done
-
-  echo "$json_obj"
-}
-
-# Parse environment variables for Linux and Windows
-linux_env_vars_json=$(parse_env_vars "$linux_env_vars" "$linux_env_var_pair_separator" "$linux_env_var_list_separator")
-windows_env_vars_json=$(parse_env_vars "$windows_env_vars" "$windows_env_var_pair_separator" "$windows_env_var_list_separator")
+# Get pre-parsed environment variables JSON
+linux_env_vars_json="${MATRIX_LINUX_ENV_VARS_JSON:-{}}"
+windows_env_vars_json="${MATRIX_WINDOWS_ENV_VARS_JSON:-{}}"
 
 # Create matrix from inputs
 matrix='{"config": []}'
diff --git a/scripts/parse_env_vars.sh b/scripts/parse_env_vars.sh
new file mode 100644
index 0000000000..24da0ea047
--- /dev/null
+++ b/scripts/parse_env_vars.sh
@@ -0,0 +1,50 @@
+#!/bin/bash
+##===----------------------------------------------------------------------===##
+##
+## This source file is part of the SwiftNIO open source project
+##
+## Copyright (c) 2024 Apple Inc. and the SwiftNIO project authors
+## Licensed under Apache License v2.0
+##
+## See LICENSE.txt for license information
+## See CONTRIBUTORS.txt for the list of SwiftNIO project authors
+##
+## SPDX-License-Identifier: Apache-2.0
+##
+##===----------------------------------------------------------------------===##
+env_vars="$ENV_VARS"
+env_var_pair_separator="${ENV_VAR_PAIR_SEPARATOR:="="}"
+env_var_list_separator="${ENV_VAR_LIST_SEPARATOR:=","}"
+
+# Function to parse environment variables and convert to JSON object
+parse_env_vars() {
+  local env_vars="$1"
+  local pair_separator="$2"
+  local list_separator="$3"
+
+  if [[ -z "$env_vars" ]]; then
+    echo "{}"
+    return
+  fi
+
+  local json_obj="{}"
+
+  # Split the env_vars string by list_separator
+  IFS="$list_separator" read -ra env_pairs <<< "$env_vars"
+
+  for pair in "${env_pairs[@]}"; do
+    # Split each pair by pair_separator
+    IFS="$pair_separator" read -ra kv <<< "$pair"
+    if [[ ${#kv[@]} -eq 2 ]]; then
+      local key="${kv[0]}"
+      local value="${kv[1]}"
+      # Add to JSON object using jq
+      json_obj=$(echo "$json_obj" | jq -c --arg key "$key" --arg value "$value" '. + {($key): $value}')
+    fi
+  done
+
+  echo "$json_obj"
+}
+
+# Execute the function with the environment variables
+parse_env_vars "$env_vars" "$env_var_pair_separator" "$env_var_list_separator"

From 40fedda2317671bbaa2e9677a69045fef6f7a532 Mon Sep 17 00:00:00 2001
From: Rick Newton-Rogers <rnro@apple.com>
Date: Fri, 19 Sep 2025 16:16:06 +0100
Subject: [PATCH 12/27] test env vars

---
 .github/workflows/pull_request.yml | 1 +
 1 file changed, 1 insertion(+)

diff --git a/.github/workflows/pull_request.yml b/.github/workflows/pull_request.yml
index 490ffe2e21..698fdf3611 100644
--- a/.github/workflows/pull_request.yml
+++ b/.github/workflows/pull_request.yml
@@ -16,6 +16,7 @@ jobs:
     # Workaround https://github.com/nektos/act/issues/1875
     uses: apple/swift-nio/.github/workflows/unit_tests.yml@matrix_custom_env_vars
     with:
+      linux_env_vars: "TEST_VAR_DEBUG=1,TEST_VAR_LOG_LEVEL=info"  # TODO: remove, testing
       linux_5_10_arguments_override: "-Xswiftc -warnings-as-errors --explicit-target-dependency-import-check error"
       linux_6_0_arguments_override: "-Xswiftc -warnings-as-errors --explicit-target-dependency-import-check error"
       linux_6_1_arguments_override: "-Xswiftc -warnings-as-errors --explicit-target-dependency-import-check error"

From a1ddcef889d50d88d3b1bdee51fac81fedf5f494 Mon Sep 17 00:00:00 2001
From: Rick Newton-Rogers <rnro@apple.com>
Date: Fri, 19 Sep 2025 16:19:30 +0100
Subject: [PATCH 13/27] more test shim

---
 .github/workflows/macos_tests.yml | 2 +-
 .github/workflows/static_sdk.yml  | 2 +-
 .github/workflows/unit_tests.yml  | 4 ++--
 3 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/.github/workflows/macos_tests.yml b/.github/workflows/macos_tests.yml
index f26b2ac0b0..748bae9673 100644
--- a/.github/workflows/macos_tests.yml
+++ b/.github/workflows/macos_tests.yml
@@ -220,7 +220,7 @@ jobs:
       - id: generate-matrix
         run: |
           # Parse environment variables using the parse_env_vars script
-          env_vars_json=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/parse_env_vars.sh | ENV_VARS="$MATRIX_ENV_VARS" ENV_VAR_PAIR_SEPARATOR="$MATRIX_ENV_VAR_PAIR_SEPARATOR" ENV_VAR_LIST_SEPARATOR="$MATRIX_ENV_VAR_LIST_SEPARATOR" bash)
+          env_vars_json=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/matrix_custom_env_vars/scripts/parse_env_vars.sh | ENV_VARS="$MATRIX_ENV_VARS" ENV_VAR_PAIR_SEPARATOR="$MATRIX_ENV_VAR_PAIR_SEPARATOR" ENV_VAR_LIST_SEPARATOR="$MATRIX_ENV_VAR_LIST_SEPARATOR" bash)
 
           cat >> "$GITHUB_OUTPUT" << EOM
           darwin-matrix=$(
diff --git a/.github/workflows/static_sdk.yml b/.github/workflows/static_sdk.yml
index d172936b5b..9efac2c4a6 100644
--- a/.github/workflows/static_sdk.yml
+++ b/.github/workflows/static_sdk.yml
@@ -30,7 +30,7 @@ jobs:
       - id: generate-matrix
         run: |
           # Parse environment variables using the parse_env_vars script
-          env_vars_json=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/parse_env_vars.sh | ENV_VARS="$MATRIX_ENV_VARS" ENV_VAR_PAIR_SEPARATOR="$MATRIX_ENV_VAR_PAIR_SEPARATOR" ENV_VAR_LIST_SEPARATOR="$MATRIX_ENV_VAR_LIST_SEPARATOR" bash)
+          env_vars_json=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/matrix_custom_env_vars/scripts/parse_env_vars.sh | ENV_VARS="$MATRIX_ENV_VARS" ENV_VAR_PAIR_SEPARATOR="$MATRIX_ENV_VAR_PAIR_SEPARATOR" ENV_VAR_LIST_SEPARATOR="$MATRIX_ENV_VAR_LIST_SEPARATOR" bash)
 
           # Generate matrix with parsed environment variables
           cat >> "$GITHUB_OUTPUT" << EOM
diff --git a/.github/workflows/unit_tests.yml b/.github/workflows/unit_tests.yml
index 70854c8984..329d288d5d 100644
--- a/.github/workflows/unit_tests.yml
+++ b/.github/workflows/unit_tests.yml
@@ -172,10 +172,10 @@ jobs:
       - id: generate-matrix
         run: |
           # Parse Linux environment variables
-          linux_env_vars_json=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/parse_env_vars.sh | ENV_VARS="${{ inputs.linux_env_vars }}" ENV_VAR_PAIR_SEPARATOR="${{ inputs.linux_env_var_pair_separator }}" ENV_VAR_LIST_SEPARATOR="${{ inputs.linux_env_var_list_separator }}" bash)
+          linux_env_vars_json=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/matrix_custom_env_vars/scripts/parse_env_vars.sh | ENV_VARS="${{ inputs.linux_env_vars }}" ENV_VAR_PAIR_SEPARATOR="${{ inputs.linux_env_var_pair_separator }}" ENV_VAR_LIST_SEPARATOR="${{ inputs.linux_env_var_list_separator }}" bash)
 
           # Parse Windows environment variables
-          windows_env_vars_json=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/parse_env_vars.sh | ENV_VARS="${{ inputs.windows_env_vars }}" ENV_VAR_PAIR_SEPARATOR="${{ inputs.windows_env_var_pair_separator }}" ENV_VAR_LIST_SEPARATOR="${{ inputs.windows_env_var_list_separator }}" bash)
+          windows_env_vars_json=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/matrix_custom_env_vars/scripts/parse_env_vars.sh | ENV_VARS="${{ inputs.windows_env_vars }}" ENV_VAR_PAIR_SEPARATOR="${{ inputs.windows_env_var_pair_separator }}" ENV_VAR_LIST_SEPARATOR="${{ inputs.windows_env_var_list_separator }}" bash)
 
           # Generate matrix
           echo "unit-test-matrix=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/matrix_custom_env_vars/scripts/generate_matrix.sh | MATRIX_LINUX_ENV_VARS_JSON="${linux_env_vars_json}" MATRIX_WINDOWS_ENV_VARS_JSON="${windows_env_vars_json}" bash)" >> "$GITHUB_OUTPUT"

From a1edbf9338b4ba1c78e65f37e0ddd6c9f39c5aae Mon Sep 17 00:00:00 2001
From: Rick Newton-Rogers <rnro@apple.com>
Date: Fri, 19 Sep 2025 16:23:15 +0100
Subject: [PATCH 14/27] test

---
 .github/workflows/unit_tests.yml | 1 +
 1 file changed, 1 insertion(+)

diff --git a/.github/workflows/unit_tests.yml b/.github/workflows/unit_tests.yml
index 329d288d5d..7439fa60ce 100644
--- a/.github/workflows/unit_tests.yml
+++ b/.github/workflows/unit_tests.yml
@@ -172,6 +172,7 @@ jobs:
       - id: generate-matrix
         run: |
           # Parse Linux environment variables
+          echo ENV_VARS="${{ inputs.linux_env_vars }}" ENV_VAR_PAIR_SEPARATOR="${{ inputs.linux_env_var_pair_separator }}" ENV_VAR_LIST_SEPARATOR="${{ inputs.linux_env_var_list_separator }}"
           linux_env_vars_json=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/matrix_custom_env_vars/scripts/parse_env_vars.sh | ENV_VARS="${{ inputs.linux_env_vars }}" ENV_VAR_PAIR_SEPARATOR="${{ inputs.linux_env_var_pair_separator }}" ENV_VAR_LIST_SEPARATOR="${{ inputs.linux_env_var_list_separator }}" bash)
 
           # Parse Windows environment variables

From 08700381510a94669821adfe47d761f6f05dc36b Mon Sep 17 00:00:00 2001
From: Rick Newton-Rogers <rnro@apple.com>
Date: Fri, 19 Sep 2025 16:29:38 +0100
Subject: [PATCH 15/27] more tests

---
 .github/workflows/unit_tests.yml | 1 -
 scripts/generate_matrix.sh       | 1 +
 scripts/parse_env_vars.sh        | 0
 3 files changed, 1 insertion(+), 1 deletion(-)
 mode change 100644 => 100755 scripts/parse_env_vars.sh

diff --git a/.github/workflows/unit_tests.yml b/.github/workflows/unit_tests.yml
index 7439fa60ce..329d288d5d 100644
--- a/.github/workflows/unit_tests.yml
+++ b/.github/workflows/unit_tests.yml
@@ -172,7 +172,6 @@ jobs:
       - id: generate-matrix
         run: |
           # Parse Linux environment variables
-          echo ENV_VARS="${{ inputs.linux_env_vars }}" ENV_VAR_PAIR_SEPARATOR="${{ inputs.linux_env_var_pair_separator }}" ENV_VAR_LIST_SEPARATOR="${{ inputs.linux_env_var_list_separator }}"
           linux_env_vars_json=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/matrix_custom_env_vars/scripts/parse_env_vars.sh | ENV_VARS="${{ inputs.linux_env_vars }}" ENV_VAR_PAIR_SEPARATOR="${{ inputs.linux_env_var_pair_separator }}" ENV_VAR_LIST_SEPARATOR="${{ inputs.linux_env_var_list_separator }}" bash)
 
           # Parse Windows environment variables
diff --git a/scripts/generate_matrix.sh b/scripts/generate_matrix.sh
index bef41e3b7e..3c17cf0ed0 100755
--- a/scripts/generate_matrix.sh
+++ b/scripts/generate_matrix.sh
@@ -12,6 +12,7 @@
 ## SPDX-License-Identifier: Apache-2.0
 ##
 ##===----------------------------------------------------------------------===##
+set -x
 
 # Parameters
 linux_command="$MATRIX_LINUX_COMMAND"  # required if any Linux pipeline is enabled
diff --git a/scripts/parse_env_vars.sh b/scripts/parse_env_vars.sh
old mode 100644
new mode 100755

From acb9bf23b5d78d0c5ffa54b63d6e3acf32edfbcf Mon Sep 17 00:00:00 2001
From: Rick Newton-Rogers <rnro@apple.com>
Date: Fri, 19 Sep 2025 16:36:22 +0100
Subject: [PATCH 16/27] testing

---
 scripts/generate_matrix.sh | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/scripts/generate_matrix.sh b/scripts/generate_matrix.sh
index 3c17cf0ed0..23fffd0f38 100755
--- a/scripts/generate_matrix.sh
+++ b/scripts/generate_matrix.sh
@@ -67,8 +67,8 @@ windows_nightly_main_runner="windows-2022"
 windows_nightly_main_container_image="swiftlang/swift:nightly-main-windowsservercore-ltsc2022"
 
 # Get pre-parsed environment variables JSON
-linux_env_vars_json="${MATRIX_LINUX_ENV_VARS_JSON:-{}}"
-windows_env_vars_json="${MATRIX_WINDOWS_ENV_VARS_JSON:-{}}"
+linux_env_vars_json="${MATRIX_LINUX_ENV_VARS_JSON:-"{}"}"
+windows_env_vars_json="${MATRIX_WINDOWS_ENV_VARS_JSON:-"{}"}"
 
 # Create matrix from inputs
 matrix='{"config": []}'

From ef725b3e1f090cc2a96459658e3480ec2f1bc2d7 Mon Sep 17 00:00:00 2001
From: Rick Newton-Rogers <rnro@apple.com>
Date: Fri, 19 Sep 2025 16:39:45 +0100
Subject: [PATCH 17/27] more testing env vars

---
 .github/workflows/pull_request.yml | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/.github/workflows/pull_request.yml b/.github/workflows/pull_request.yml
index 698fdf3611..961e084f97 100644
--- a/.github/workflows/pull_request.yml
+++ b/.github/workflows/pull_request.yml
@@ -86,6 +86,7 @@ jobs:
     with:
       runner_pool: general
       build_scheme: swift-nio-Package
+      env_vars: "TEST_VAR_DEBUG=1,TEST_VAR_LOG_LEVEL=info"  # TODO: remove, testing
       xcode_16_2_build_arguments_override: "-Xswiftc -Xfrontend -Xswiftc -require-explicit-sendable"
       xcode_16_3_build_arguments_override: "-Xswiftc -Xfrontend -Xswiftc -require-explicit-sendable"
 
@@ -93,6 +94,8 @@ jobs:
     name: Static Linux Swift SDK
     # Workaround https://github.com/nektos/act/issues/1875
     uses: apple/swift-nio/.github/workflows/static_sdk.yml@matrix_custom_env_vars
+    with:
+      env_vars: "TEST_VAR_DEBUG=1,TEST_VAR_LOG_LEVEL=info"  # TODO: remove, testing
 
   wasm-sdk:
     name: WebAssembly Swift SDK

From a326bad4e72d43d08a27e52883a9673c764bf5f7 Mon Sep 17 00:00:00 2001
From: Rick Newton-Rogers <rnro@apple.com>
Date: Fri, 19 Sep 2025 16:48:09 +0100
Subject: [PATCH 18/27] export on macos

---
 .github/workflows/macos_tests.yml | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/.github/workflows/macos_tests.yml b/.github/workflows/macos_tests.yml
index 748bae9673..500d1c276e 100644
--- a/.github/workflows/macos_tests.yml
+++ b/.github/workflows/macos_tests.yml
@@ -404,6 +404,12 @@ jobs:
         with:
           persist-credentials: false
           submodules: true
+      - name: Export environment variables
+        if: ${{ matrix.config.env != '' && matrix.config.env != '{}'}}
+        run: |
+          echo "Exporting environment variables from matrix configuration..."
+          echo '${{ toJSON(matrix.config.env) }}' | jq -r 'to_entries[] | "\(.key)=\(.value)"' >> $GITHUB_ENV
+          echo '${{ toJSON(matrix.config.env) }}' | jq -r 'to_entries[] | "\(.key)=\(.value)"'
       - name: Setup command
         if: ${{ matrix.config.setup_command != '' }}
         run: bash -c "${{ matrix.config.setup_command }}"

From 7a9a174359a008b713b0d9a8f62417659bc72e4a Mon Sep 17 00:00:00 2001
From: Rick Newton-Rogers <rnro@apple.com>
Date: Fri, 19 Sep 2025 17:01:51 +0100
Subject: [PATCH 19/27] tweaks

---
 .github/workflows/macos_tests.yml | 2 +-
 scripts/parse_env_vars.sh         | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/.github/workflows/macos_tests.yml b/.github/workflows/macos_tests.yml
index 500d1c276e..2957e605c2 100644
--- a/.github/workflows/macos_tests.yml
+++ b/.github/workflows/macos_tests.yml
@@ -409,7 +409,7 @@ jobs:
         run: |
           echo "Exporting environment variables from matrix configuration..."
           echo '${{ toJSON(matrix.config.env) }}' | jq -r 'to_entries[] | "\(.key)=\(.value)"' >> $GITHUB_ENV
-          echo '${{ toJSON(matrix.config.env) }}' | jq -r 'to_entries[] | "\(.key)=\(.value)"'
+          echo '${{ toJSON(matrix.config.env) }}' | jq -r 'to_entries[] | "exporting \(.key)=\(.value)"'
       - name: Setup command
         if: ${{ matrix.config.setup_command != '' }}
         run: bash -c "${{ matrix.config.setup_command }}"
diff --git a/scripts/parse_env_vars.sh b/scripts/parse_env_vars.sh
index 24da0ea047..7c01da29c3 100755
--- a/scripts/parse_env_vars.sh
+++ b/scripts/parse_env_vars.sh
@@ -12,7 +12,7 @@
 ## SPDX-License-Identifier: Apache-2.0
 ##
 ##===----------------------------------------------------------------------===##
-env_vars="$ENV_VARS"
+env_vars="${$ENV_VARS:=""}"
 env_var_pair_separator="${ENV_VAR_PAIR_SEPARATOR:="="}"
 env_var_list_separator="${ENV_VAR_LIST_SEPARATOR:=","}"
 

From bfe8591e19f4476db69ce4f266f3d4551788a6c7 Mon Sep 17 00:00:00 2001
From: Rick Newton-Rogers <rnro@apple.com>
Date: Fri, 19 Sep 2025 17:40:12 +0100
Subject: [PATCH 20/27] fix

---
 scripts/parse_env_vars.sh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/scripts/parse_env_vars.sh b/scripts/parse_env_vars.sh
index 7c01da29c3..bc6529db6a 100755
--- a/scripts/parse_env_vars.sh
+++ b/scripts/parse_env_vars.sh
@@ -12,7 +12,7 @@
 ## SPDX-License-Identifier: Apache-2.0
 ##
 ##===----------------------------------------------------------------------===##
-env_vars="${$ENV_VARS:=""}"
+env_vars="${ENV_VARS:=""}"
 env_var_pair_separator="${ENV_VAR_PAIR_SEPARATOR:="="}"
 env_var_list_separator="${ENV_VAR_LIST_SEPARATOR:=","}"
 

From eb1d46ccc01e93b23807a33daae5c689d48193ae Mon Sep 17 00:00:00 2001
From: Rick Newton-Rogers <rnro@apple.com>
Date: Fri, 19 Sep 2025 17:47:28 +0100
Subject: [PATCH 21/27] unpick testing shims and variables

---
 .github/workflows/benchmarks.yml             |  2 +-
 .github/workflows/cxx_interop.yml            |  2 +-
 .github/workflows/macos_tests.yml            |  2 +-
 .github/workflows/main.yml                   | 16 ++++++++--------
 .github/workflows/pull_request.yml           | 16 ++++++++--------
 .github/workflows/release_builds.yml         |  2 +-
 .github/workflows/static_sdk.yml             |  4 ++--
 .github/workflows/swift_load_test_matrix.yml |  2 +-
 .github/workflows/unit_tests.yml             |  8 ++++----
 9 files changed, 27 insertions(+), 27 deletions(-)

diff --git a/.github/workflows/benchmarks.yml b/.github/workflows/benchmarks.yml
index 22a5844387..4de9bc0581 100644
--- a/.github/workflows/benchmarks.yml
+++ b/.github/workflows/benchmarks.yml
@@ -112,7 +112,7 @@ jobs:
     name: Benchmarks
     needs: construct-matrix
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@matrix_custom_env_vars
+    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@main
     with:
       name: "Benchmarks"
       matrix_string: '${{ needs.construct-matrix.outputs.benchmarks-matrix }}'
diff --git a/.github/workflows/cxx_interop.yml b/.github/workflows/cxx_interop.yml
index d0ba3f3182..e90e228260 100644
--- a/.github/workflows/cxx_interop.yml
+++ b/.github/workflows/cxx_interop.yml
@@ -120,7 +120,7 @@ jobs:
     name: Cxx interop
     needs: construct-matrix
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@matrix_custom_env_vars
+    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@main
     with:
       name: "Cxx interop"
       matrix_string: '${{ needs.construct-matrix.outputs.cxx-interop-matrix }}'
diff --git a/.github/workflows/macos_tests.yml b/.github/workflows/macos_tests.yml
index 2957e605c2..6eac211245 100644
--- a/.github/workflows/macos_tests.yml
+++ b/.github/workflows/macos_tests.yml
@@ -220,7 +220,7 @@ jobs:
       - id: generate-matrix
         run: |
           # Parse environment variables using the parse_env_vars script
-          env_vars_json=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/matrix_custom_env_vars/scripts/parse_env_vars.sh | ENV_VARS="$MATRIX_ENV_VARS" ENV_VAR_PAIR_SEPARATOR="$MATRIX_ENV_VAR_PAIR_SEPARATOR" ENV_VAR_LIST_SEPARATOR="$MATRIX_ENV_VAR_LIST_SEPARATOR" bash)
+          env_vars_json=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/parse_env_vars.sh | ENV_VARS="$MATRIX_ENV_VARS" ENV_VAR_PAIR_SEPARATOR="$MATRIX_ENV_VAR_PAIR_SEPARATOR" ENV_VAR_LIST_SEPARATOR="$MATRIX_ENV_VAR_LIST_SEPARATOR" bash)
 
           cat >> "$GITHUB_OUTPUT" << EOM
           darwin-matrix=$(
diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 5c9ad3702c..5178bcce81 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -10,7 +10,7 @@ jobs:
   unit-tests:
     name: Unit tests
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/unit_tests.yml@matrix_custom_env_vars
+    uses: apple/swift-nio/.github/workflows/unit_tests.yml@main
     with:
       linux_5_10_arguments_override: "-Xswiftc -warnings-as-errors --explicit-target-dependency-import-check error"
       linux_6_0_arguments_override: "-Xswiftc -warnings-as-errors --explicit-target-dependency-import-check error"
@@ -22,12 +22,12 @@ jobs:
   cxx-interop:
     name: Cxx interop
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/cxx_interop.yml@matrix_custom_env_vars
+    uses: apple/swift-nio/.github/workflows/cxx_interop.yml@main
 
   benchmarks:
     name: Benchmarks
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/benchmarks.yml@matrix_custom_env_vars
+    uses: apple/swift-nio/.github/workflows/benchmarks.yml@main
     with:
       benchmark_package_path: "Benchmarks"
 
@@ -51,7 +51,7 @@ jobs:
     name: Integration tests
     needs: construct-integration-test-matrix
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@matrix_custom_env_vars
+    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@main
     with:
       name: "Integration tests"
       matrix_string: '${{ needs.construct-integration-test-matrix.outputs.integration-test-matrix }}'
@@ -59,17 +59,17 @@ jobs:
   static-sdk:
     name: Static Linux Swift SDK
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/static_sdk.yml@matrix_custom_env_vars
+    uses: apple/swift-nio/.github/workflows/static_sdk.yml@main
 
   wasm-sdk:
     name: WebAssembly Swift SDK
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/wasm_sdk.yml@matrix_custom_env_vars
+    uses: apple/swift-nio/.github/workflows/wasm_sdk.yml@main
 
   macos-tests:
     name: macOS tests
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/macos_tests.yml@matrix_custom_env_vars
+    uses: apple/swift-nio/.github/workflows/macos_tests.yml@main
     with:
       runner_pool: nightly
       build_scheme: swift-nio-Package
@@ -83,4 +83,4 @@ jobs:
 
   release-builds:
     name: Release builds
-    uses: apple/swift-nio/.github/workflows/release_builds.yml@matrix_custom_env_vars
+    uses: apple/swift-nio/.github/workflows/release_builds.yml@main
diff --git a/.github/workflows/pull_request.yml b/.github/workflows/pull_request.yml
index 961e084f97..05f5cef07a 100644
--- a/.github/workflows/pull_request.yml
+++ b/.github/workflows/pull_request.yml
@@ -14,7 +14,7 @@ jobs:
   unit-tests:
     name: Unit tests
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/unit_tests.yml@matrix_custom_env_vars
+    uses: apple/swift-nio/.github/workflows/unit_tests.yml@main
     with:
       linux_env_vars: "TEST_VAR_DEBUG=1,TEST_VAR_LOG_LEVEL=info"  # TODO: remove, testing
       linux_5_10_arguments_override: "-Xswiftc -warnings-as-errors --explicit-target-dependency-import-check error"
@@ -27,14 +27,14 @@ jobs:
   benchmarks:
     name: Benchmarks
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/benchmarks.yml@matrix_custom_env_vars
+    uses: apple/swift-nio/.github/workflows/benchmarks.yml@main
     with:
       benchmark_package_path: "Benchmarks"
 
   cxx-interop:
     name: Cxx interop
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/cxx_interop.yml@matrix_custom_env_vars
+    uses: apple/swift-nio/.github/workflows/cxx_interop.yml@main
 
   construct-integration-test-matrix:
     name: Construct integration test matrix
@@ -56,7 +56,7 @@ jobs:
     name: Integration tests
     needs: construct-integration-test-matrix
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@matrix_custom_env_vars
+    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@main
     with:
       name: "Integration tests"
       matrix_string: '${{ needs.construct-integration-test-matrix.outputs.integration-test-matrix }}'
@@ -82,7 +82,7 @@ jobs:
   macos-tests:
     name: macOS tests
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/macos_tests.yml@matrix_custom_env_vars
+    uses: apple/swift-nio/.github/workflows/macos_tests.yml@main
     with:
       runner_pool: general
       build_scheme: swift-nio-Package
@@ -93,15 +93,15 @@ jobs:
   static-sdk:
     name: Static Linux Swift SDK
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/static_sdk.yml@matrix_custom_env_vars
+    uses: apple/swift-nio/.github/workflows/static_sdk.yml@main
     with:
       env_vars: "TEST_VAR_DEBUG=1,TEST_VAR_LOG_LEVEL=info"  # TODO: remove, testing
 
   wasm-sdk:
     name: WebAssembly Swift SDK
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/wasm_sdk.yml@matrix_custom_env_vars
+    uses: apple/swift-nio/.github/workflows/wasm_sdk.yml@main
 
   release-builds:
     name: Release builds
-    uses: apple/swift-nio/.github/workflows/release_builds.yml@matrix_custom_env_vars
+    uses: apple/swift-nio/.github/workflows/release_builds.yml@main
diff --git a/.github/workflows/release_builds.yml b/.github/workflows/release_builds.yml
index 3fbfbe6f98..fd5880c835 100644
--- a/.github/workflows/release_builds.yml
+++ b/.github/workflows/release_builds.yml
@@ -168,7 +168,7 @@ jobs:
     name: Release builds
     needs: construct-matrix
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@matrix_custom_env_vars
+    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@main
     with:
       name: "Release builds"
       matrix_string: '${{ needs.construct-matrix.outputs.release-build-matrix }}'
diff --git a/.github/workflows/static_sdk.yml b/.github/workflows/static_sdk.yml
index 9efac2c4a6..48dab11cdb 100644
--- a/.github/workflows/static_sdk.yml
+++ b/.github/workflows/static_sdk.yml
@@ -30,7 +30,7 @@ jobs:
       - id: generate-matrix
         run: |
           # Parse environment variables using the parse_env_vars script
-          env_vars_json=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/matrix_custom_env_vars/scripts/parse_env_vars.sh | ENV_VARS="$MATRIX_ENV_VARS" ENV_VAR_PAIR_SEPARATOR="$MATRIX_ENV_VAR_PAIR_SEPARATOR" ENV_VAR_LIST_SEPARATOR="$MATRIX_ENV_VAR_LIST_SEPARATOR" bash)
+          env_vars_json=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/parse_env_vars.sh | ENV_VARS="$MATRIX_ENV_VARS" ENV_VAR_PAIR_SEPARATOR="$MATRIX_ENV_VAR_PAIR_SEPARATOR" ENV_VAR_LIST_SEPARATOR="$MATRIX_ENV_VAR_LIST_SEPARATOR" bash)
 
           # Generate matrix with parsed environment variables
           cat >> "$GITHUB_OUTPUT" << EOM
@@ -70,7 +70,7 @@ jobs:
     name: Static SDK
     needs: construct-matrix
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@matrix_custom_env_vars
+    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@main
     with:
       name: "Static SDK"
       matrix_string: '${{ needs.construct-matrix.outputs.static-sdk-matrix }}'
diff --git a/.github/workflows/swift_load_test_matrix.yml b/.github/workflows/swift_load_test_matrix.yml
index 12b2df5c12..9b7b53b7f2 100644
--- a/.github/workflows/swift_load_test_matrix.yml
+++ b/.github/workflows/swift_load_test_matrix.yml
@@ -35,7 +35,7 @@ jobs:
     name: Execute matrix
     needs: load-matrix
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@matrix_custom_env_vars
+    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@main
     with:
       name: ${{ inputs.name }}
       matrix_string: '${{ needs.load-matrix.outputs.swift-matrix }}'
diff --git a/.github/workflows/unit_tests.yml b/.github/workflows/unit_tests.yml
index 329d288d5d..6356fc1145 100644
--- a/.github/workflows/unit_tests.yml
+++ b/.github/workflows/unit_tests.yml
@@ -172,13 +172,13 @@ jobs:
       - id: generate-matrix
         run: |
           # Parse Linux environment variables
-          linux_env_vars_json=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/matrix_custom_env_vars/scripts/parse_env_vars.sh | ENV_VARS="${{ inputs.linux_env_vars }}" ENV_VAR_PAIR_SEPARATOR="${{ inputs.linux_env_var_pair_separator }}" ENV_VAR_LIST_SEPARATOR="${{ inputs.linux_env_var_list_separator }}" bash)
+          linux_env_vars_json=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/parse_env_vars.sh | ENV_VARS="${{ inputs.linux_env_vars }}" ENV_VAR_PAIR_SEPARATOR="${{ inputs.linux_env_var_pair_separator }}" ENV_VAR_LIST_SEPARATOR="${{ inputs.linux_env_var_list_separator }}" bash)
 
           # Parse Windows environment variables
-          windows_env_vars_json=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/matrix_custom_env_vars/scripts/parse_env_vars.sh | ENV_VARS="${{ inputs.windows_env_vars }}" ENV_VAR_PAIR_SEPARATOR="${{ inputs.windows_env_var_pair_separator }}" ENV_VAR_LIST_SEPARATOR="${{ inputs.windows_env_var_list_separator }}" bash)
+          windows_env_vars_json=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/parse_env_vars.sh | ENV_VARS="${{ inputs.windows_env_vars }}" ENV_VAR_PAIR_SEPARATOR="${{ inputs.windows_env_var_pair_separator }}" ENV_VAR_LIST_SEPARATOR="${{ inputs.windows_env_var_list_separator }}" bash)
 
           # Generate matrix
-          echo "unit-test-matrix=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/matrix_custom_env_vars/scripts/generate_matrix.sh | MATRIX_LINUX_ENV_VARS_JSON="${linux_env_vars_json}" MATRIX_WINDOWS_ENV_VARS_JSON="${windows_env_vars_json}" bash)" >> "$GITHUB_OUTPUT"
+          echo "unit-test-matrix=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/generate_matrix.sh | MATRIX_LINUX_ENV_VARS_JSON="${linux_env_vars_json}" MATRIX_WINDOWS_ENV_VARS_JSON="${windows_env_vars_json}" bash)" >> "$GITHUB_OUTPUT"
         env:
           MATRIX_LINUX_SETUP_COMMAND: "swift --version"
           MATRIX_LINUX_COMMAND: "swift test"
@@ -212,7 +212,7 @@ jobs:
     name: Unit tests
     needs: construct-matrix
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@matrix_custom_env_vars
+    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@main
     with:
       name: "Unit tests"
       matrix_string: '${{ needs.construct-matrix.outputs.unit-test-matrix }}'

From caabec76d9044ecd2e6292210d77984d6ca3e8e1 Mon Sep 17 00:00:00 2001
From: Rick Newton-Rogers <rnro@apple.com>
Date: Fri, 19 Sep 2025 17:56:26 +0100
Subject: [PATCH 22/27] update license

---
 scripts/parse_env_vars.sh | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/scripts/parse_env_vars.sh b/scripts/parse_env_vars.sh
index bc6529db6a..1e48fa28e7 100755
--- a/scripts/parse_env_vars.sh
+++ b/scripts/parse_env_vars.sh
@@ -3,7 +3,7 @@
 ##
 ## This source file is part of the SwiftNIO open source project
 ##
-## Copyright (c) 2024 Apple Inc. and the SwiftNIO project authors
+## Copyright (c) 2025 Apple Inc. and the SwiftNIO project authors
 ## Licensed under Apache License v2.0
 ##
 ## See LICENSE.txt for license information
@@ -12,6 +12,7 @@
 ## SPDX-License-Identifier: Apache-2.0
 ##
 ##===----------------------------------------------------------------------===##
+
 env_vars="${ENV_VARS:=""}"
 env_var_pair_separator="${ENV_VAR_PAIR_SEPARATOR:="="}"
 env_var_list_separator="${ENV_VAR_LIST_SEPARATOR:=","}"

From 7902b6ea6f91a4267f36735b9217d89e7e71e1f2 Mon Sep 17 00:00:00 2001
From: Rick Newton-Rogers <rnro@apple.com>
Date: Mon, 22 Sep 2025 09:44:11 +0100
Subject: [PATCH 23/27] remove testing params

---
 .github/workflows/pull_request.yml | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/.github/workflows/pull_request.yml b/.github/workflows/pull_request.yml
index 05f5cef07a..f171e1de5b 100644
--- a/.github/workflows/pull_request.yml
+++ b/.github/workflows/pull_request.yml
@@ -16,7 +16,6 @@ jobs:
     # Workaround https://github.com/nektos/act/issues/1875
     uses: apple/swift-nio/.github/workflows/unit_tests.yml@main
     with:
-      linux_env_vars: "TEST_VAR_DEBUG=1,TEST_VAR_LOG_LEVEL=info"  # TODO: remove, testing
       linux_5_10_arguments_override: "-Xswiftc -warnings-as-errors --explicit-target-dependency-import-check error"
       linux_6_0_arguments_override: "-Xswiftc -warnings-as-errors --explicit-target-dependency-import-check error"
       linux_6_1_arguments_override: "-Xswiftc -warnings-as-errors --explicit-target-dependency-import-check error"
@@ -86,7 +85,6 @@ jobs:
     with:
       runner_pool: general
       build_scheme: swift-nio-Package
-      env_vars: "TEST_VAR_DEBUG=1,TEST_VAR_LOG_LEVEL=info"  # TODO: remove, testing
       xcode_16_2_build_arguments_override: "-Xswiftc -Xfrontend -Xswiftc -require-explicit-sendable"
       xcode_16_3_build_arguments_override: "-Xswiftc -Xfrontend -Xswiftc -require-explicit-sendable"
 
@@ -94,8 +92,6 @@ jobs:
     name: Static Linux Swift SDK
     # Workaround https://github.com/nektos/act/issues/1875
     uses: apple/swift-nio/.github/workflows/static_sdk.yml@main
-    with:
-      env_vars: "TEST_VAR_DEBUG=1,TEST_VAR_LOG_LEVEL=info"  # TODO: remove, testing
 
   wasm-sdk:
     name: WebAssembly Swift SDK

From 605059361babd5bc732625c3d6fc46a4048ca70b Mon Sep 17 00:00:00 2001
From: Rick Newton-Rogers <rnro@apple.com>
Date: Mon, 22 Sep 2025 11:35:48 +0100
Subject: [PATCH 24/27] matrix env vars as JSON

---
 .github/workflows/benchmarks.yml     | 26 +++++++-------
 .github/workflows/cxx_interop.yml    | 47 +++++++++++--------------
 .github/workflows/macos_tests.yml    | 25 ++++++--------
 .github/workflows/release_builds.yml | 47 +++++++++++--------------
 .github/workflows/static_sdk.yml     | 25 ++++++--------
 .github/workflows/unit_tests.yml     | 41 ++++++++++------------
 scripts/parse_env_vars.sh            | 51 ----------------------------
 7 files changed, 89 insertions(+), 173 deletions(-)
 delete mode 100755 scripts/parse_env_vars.sh

diff --git a/.github/workflows/benchmarks.yml b/.github/workflows/benchmarks.yml
index 4de9bc0581..31605140f0 100644
--- a/.github/workflows/benchmarks.yml
+++ b/.github/workflows/benchmarks.yml
@@ -70,16 +70,8 @@ on:
 
       linux_env_vars:
         type: string
-        description: "Environment variables for Linux jobs (e.g., 'DEBUG=1,LOG_LEVEL=info')."
-        default: ""
-      linux_env_var_pair_separator:
-        type: string
-        description: "Separator between key and value for Linux environment variables."
-        default: "="
-      linux_env_var_list_separator:
-        type: string
-        description: "Separator between environment variable pairs for Linux."
-        default: ","
+        description: "Environment variables for Linux jobs as JSON (e.g., '{\"DEBUG\":\"1\",\"LOG_LEVEL\":\"info\"}')."
+        default: "{}"
 
 jobs:
   construct-matrix:
@@ -93,13 +85,19 @@ jobs:
         with:
           persist-credentials: false
       - id: generate-matrix
-        run: echo "benchmarks-matrix=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/generate_matrix.sh | bash)" >> "$GITHUB_OUTPUT"
+        run: |
+          # Validate JSON environment variables
+          linux_env_vars_json='${{ inputs.linux_env_vars }}'
+
+          if ! echo "$linux_env_vars_json" | jq empty 2>/dev/null; then
+            echo "Error: linux_env_vars is not valid JSON"
+            exit 1
+          fi
+
+          echo "benchmarks-matrix=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/generate_matrix.sh | MATRIX_LINUX_ENV_VARS_JSON="${linux_env_vars_json}" bash)" >> "$GITHUB_OUTPUT"
         env:
           MATRIX_LINUX_COMMAND: "curl -s https://raw.githubusercontent.com/apple/swift-nio/main/scripts/check_benchmark_thresholds.sh | BENCHMARK_PACKAGE_PATH=${{ inputs.benchmark_package_path }} bash"
           MATRIX_LINUX_SETUP_COMMAND: "swift --version && apt-get update -y -q && apt-get install -y -q curl libjemalloc-dev && git config --global --add safe.directory /$(basename ${{ github.workspace }})"
-          MATRIX_LINUX_ENV_VARS: ${{ inputs.linux_env_vars }}
-          MATRIX_LINUX_ENV_VAR_PAIR_SEPARATOR: ${{ inputs.linux_env_var_pair_separator }}
-          MATRIX_LINUX_ENV_VAR_LIST_SEPARATOR: ${{ inputs.linux_env_var_list_separator }}
           MATRIX_LINUX_5_9_ENABLED: ${{ inputs.linux_5_9_enabled }}
           MATRIX_LINUX_5_10_ENABLED: ${{ inputs.linux_5_10_enabled }}
           MATRIX_LINUX_6_0_ENABLED: ${{ inputs.linux_6_0_enabled }}
diff --git a/.github/workflows/cxx_interop.yml b/.github/workflows/cxx_interop.yml
index e90e228260..5076619e23 100644
--- a/.github/workflows/cxx_interop.yml
+++ b/.github/workflows/cxx_interop.yml
@@ -63,28 +63,12 @@ on:
 
       linux_env_vars:
         type: string
-        description: "Environment variables for Linux jobs (e.g., 'DEBUG=1,LOG_LEVEL=info')."
-        default: ""
-      linux_env_var_pair_separator:
-        type: string
-        description: "Separator between key and value for Linux environment variables."
-        default: "="
-      linux_env_var_list_separator:
-        type: string
-        description: "Separator between environment variable pairs for Linux."
-        default: ","
+        description: "Environment variables for Linux jobs as JSON (e.g., '{\"DEBUG\":\"1\",\"LOG_LEVEL\":\"info\"}')."
+        default: "{}"
       windows_env_vars:
         type: string
-        description: "Environment variables for Windows jobs (e.g., 'DEBUG=1,LOG_LEVEL=info')."
-        default: ""
-      windows_env_var_pair_separator:
-        type: string
-        description: "Separator between key and value for Windows environment variables."
-        default: "="
-      windows_env_var_list_separator:
-        type: string
-        description: "Separator between environment variable pairs for Windows."
-        default: ","
+        description: "Environment variables for Windows jobs as JSON (e.g., '{\"DEBUG\":\"1\",\"LOG_LEVEL\":\"info\"}')."
+        default: "{}"
 
 jobs:
   construct-matrix:
@@ -98,13 +82,25 @@ jobs:
         with:
           persist-credentials: false
       - id: generate-matrix
-        run: echo "cxx-interop-matrix=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/generate_matrix.sh | bash)" >> "$GITHUB_OUTPUT"
+        run: |
+          # Validate JSON environment variables
+          linux_env_vars_json='${{ inputs.linux_env_vars }}'
+          windows_env_vars_json='${{ inputs.windows_env_vars }}'
+
+          if ! echo "$linux_env_vars_json" | jq empty 2>/dev/null; then
+            echo "Error: linux_env_vars is not valid JSON"
+            exit 1
+          fi
+
+          if ! echo "$windows_env_vars_json" | jq empty 2>/dev/null; then
+            echo "Error: windows_env_vars is not valid JSON"
+            exit 1
+          fi
+
+          echo "cxx-interop-matrix=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/generate_matrix.sh | MATRIX_LINUX_ENV_VARS_JSON="${linux_env_vars_json}" MATRIX_WINDOWS_ENV_VARS_JSON="${windows_env_vars_json}" bash)" >> "$GITHUB_OUTPUT"
         env:
           MATRIX_LINUX_COMMAND: "curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/check-cxx-interop-compatibility.sh | bash"
           MATRIX_LINUX_SETUP_COMMAND: "swift --version && apt-get update -y -q && apt-get install -y -q curl jq"
-          MATRIX_LINUX_ENV_VARS: ${{ inputs.linux_env_vars }}
-          MATRIX_LINUX_ENV_VAR_PAIR_SEPARATOR: ${{ inputs.linux_env_var_pair_separator }}
-          MATRIX_LINUX_ENV_VAR_LIST_SEPARATOR: ${{ inputs.linux_env_var_list_separator }}
           MATRIX_LINUX_5_9_ENABLED: ${{ inputs.linux_5_9_enabled }}
           MATRIX_LINUX_5_10_ENABLED: ${{ inputs.linux_5_10_enabled }}
           MATRIX_LINUX_6_0_ENABLED: ${{ inputs.linux_6_0_enabled }}
@@ -112,9 +108,6 @@ jobs:
           MATRIX_LINUX_6_2_ENABLED: ${{ inputs.linux_6_2_enabled }}
           MATRIX_LINUX_NIGHTLY_NEXT_ENABLED: ${{ inputs.linux_nightly_6_1_enabled && inputs.linux_nightly_next_enabled }}
           MATRIX_LINUX_NIGHTLY_MAIN_ENABLED: ${{ inputs.linux_nightly_main_enabled }}
-          MATRIX_WINDOWS_ENV_VARS: ${{ inputs.windows_env_vars }}
-          MATRIX_WINDOWS_ENV_VAR_PAIR_SEPARATOR: ${{ inputs.windows_env_var_pair_separator }}
-          MATRIX_WINDOWS_ENV_VAR_LIST_SEPARATOR: ${{ inputs.windows_env_var_list_separator }}
 
   cxx-interop:
     name: Cxx interop
diff --git a/.github/workflows/macos_tests.yml b/.github/workflows/macos_tests.yml
index 6eac211245..73f8b6c769 100644
--- a/.github/workflows/macos_tests.yml
+++ b/.github/workflows/macos_tests.yml
@@ -195,16 +195,8 @@ on:
 
       env_vars:
         type: string
-        description: "Environment variables for jobs (e.g., 'DEBUG=1,LOG_LEVEL=info')."
-        default: ""
-      env_var_pair_separator:
-        type: string
-        description: "Separator between key and value for environment variables."
-        default: "="
-      env_var_list_separator:
-        type: string
-        description: "Separator between environment variable pairs."
-        default: ","
+        description: "Environment variables for jobs as JSON (e.g., '{\"DEBUG\":\"1\",\"LOG_LEVEL\":\"info\"}')."
+        default: "{}"
 
 jobs:
   construct-matrix:
@@ -219,8 +211,14 @@ jobs:
           persist-credentials: false
       - id: generate-matrix
         run: |
-          # Parse environment variables using the parse_env_vars script
-          env_vars_json=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/parse_env_vars.sh | ENV_VARS="$MATRIX_ENV_VARS" ENV_VAR_PAIR_SEPARATOR="$MATRIX_ENV_VAR_PAIR_SEPARATOR" ENV_VAR_LIST_SEPARATOR="$MATRIX_ENV_VAR_LIST_SEPARATOR" bash)
+          # Validate and use JSON environment variables directly
+          env_vars_json='${{ inputs.env_vars }}'
+
+          # Validate JSON format
+          if ! echo "$env_vars_json" | jq empty 2>/dev/null; then
+            echo "Error: env_vars is not valid JSON"
+            exit 1
+          fi
 
           cat >> "$GITHUB_OUTPUT" << EOM
           darwin-matrix=$(
@@ -349,9 +347,6 @@ jobs:
           )"
           EOM
         env:
-          MATRIX_ENV_VARS: ${{ inputs.env_vars }}
-          MATRIX_ENV_VAR_PAIR_SEPARATOR: ${{ inputs.env_var_pair_separator }}
-          MATRIX_ENV_VAR_LIST_SEPARATOR: ${{ inputs.env_var_list_separator }}
           MATRIX_RUNNER_POOL: ${{ inputs.runner_pool }}
           MATRIX_MACOS_15_4_ENABLED: ${{ inputs.xcode_15_4_enabled }}
           MATRIX_MACOS_15_4_BUILD_ARGUMENTS_OVERRIDE: ${{ inputs.xcode_15_4_build_arguments_override }}
diff --git a/.github/workflows/release_builds.yml b/.github/workflows/release_builds.yml
index fd5880c835..6c605b5679 100644
--- a/.github/workflows/release_builds.yml
+++ b/.github/workflows/release_builds.yml
@@ -95,28 +95,12 @@ on:
 
       linux_env_vars:
         type: string
-        description: "Environment variables for Linux jobs (e.g., 'DEBUG=1,LOG_LEVEL=info')."
-        default: ""
-      linux_env_var_pair_separator:
-        type: string
-        description: "Separator between key and value for Linux environment variables."
-        default: "="
-      linux_env_var_list_separator:
-        type: string
-        description: "Separator between environment variable pairs for Linux."
-        default: ","
+        description: "Environment variables for Linux jobs as JSON (e.g., '{\"DEBUG\":\"1\",\"LOG_LEVEL\":\"info\"}')."
+        default: "{}"
       windows_env_vars:
         type: string
-        description: "Environment variables for Windows jobs (e.g., 'DEBUG=1,LOG_LEVEL=info')."
-        default: ""
-      windows_env_var_pair_separator:
-        type: string
-        description: "Separator between key and value for Windows environment variables."
-        default: "="
-      windows_env_var_list_separator:
-        type: string
-        description: "Separator between environment variable pairs for Windows."
-        default: ","
+        description: "Environment variables for Windows jobs as JSON (e.g., '{\"DEBUG\":\"1\",\"LOG_LEVEL\":\"info\"}')."
+        default: "{}"
 
 jobs:
   construct-matrix:
@@ -130,13 +114,25 @@ jobs:
         with:
           persist-credentials: false
       - id: generate-matrix
-        run: echo "release-build-matrix=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/generate_matrix.sh | bash)" >> "$GITHUB_OUTPUT"
+        run: |
+          # Validate JSON environment variables
+          linux_env_vars_json='${{ inputs.linux_env_vars }}'
+          windows_env_vars_json='${{ inputs.windows_env_vars }}'
+
+          if ! echo "$linux_env_vars_json" | jq empty 2>/dev/null; then
+            echo "Error: linux_env_vars is not valid JSON"
+            exit 1
+          fi
+
+          if ! echo "$windows_env_vars_json" | jq empty 2>/dev/null; then
+            echo "Error: windows_env_vars is not valid JSON"
+            exit 1
+          fi
+
+          echo "release-build-matrix=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/generate_matrix.sh | MATRIX_LINUX_ENV_VARS_JSON="${linux_env_vars_json}" MATRIX_WINDOWS_ENV_VARS_JSON="${windows_env_vars_json}" bash)" >> "$GITHUB_OUTPUT"
         env:
           MATRIX_LINUX_SETUP_COMMAND: "swift --version"
           MATRIX_LINUX_COMMAND: "swift build -c release"
-          MATRIX_LINUX_ENV_VARS: ${{ inputs.linux_env_vars }}
-          MATRIX_LINUX_ENV_VAR_PAIR_SEPARATOR: ${{ inputs.linux_env_var_pair_separator }}
-          MATRIX_LINUX_ENV_VAR_LIST_SEPARATOR: ${{ inputs.linux_env_var_list_separator }}
           MATRIX_LINUX_5_10_ENABLED: ${{ inputs.linux_5_10_enabled }}
           MATRIX_LINUX_5_10_COMMAND_ARGUMENTS: ${{ inputs.linux_5_10_arguments_override }}
           MATRIX_LINUX_6_0_ENABLED: ${{ inputs.linux_6_0_enabled }}
@@ -160,9 +156,6 @@ jobs:
           MATRIX_WINDOWS_NIGHTLY_NEXT_COMMAND_ARGUMENTS: ${{ inputs.windows_nightly_next_arguments_override }}
           MATRIX_WINDOWS_NIGHTLY_MAIN_ENABLED: ${{ inputs.windows_nightly_main_enabled }}
           MATRIX_WINDOWS_NIGHTLY_MAIN_COMMAND_ARGUMENTS: ${{ inputs.windows_nightly_main_arguments_override }}
-          MATRIX_WINDOWS_ENV_VARS: ${{ inputs.windows_env_vars }}
-          MATRIX_WINDOWS_ENV_VAR_PAIR_SEPARATOR: ${{ inputs.windows_env_var_pair_separator }}
-          MATRIX_WINDOWS_ENV_VAR_LIST_SEPARATOR: ${{ inputs.windows_env_var_list_separator }}
 
   release-builds:
     name: Release builds
diff --git a/.github/workflows/static_sdk.yml b/.github/workflows/static_sdk.yml
index 48dab11cdb..bbd32caec4 100644
--- a/.github/workflows/static_sdk.yml
+++ b/.github/workflows/static_sdk.yml
@@ -5,16 +5,8 @@ on:
     inputs:
       env_vars:
         type: string
-        description: "Environment variables for jobs (e.g., 'DEBUG=1,LOG_LEVEL=info')."
-        default: ""
-      env_var_pair_separator:
-        type: string
-        description: "Separator between key and value for environment variables."
-        default: "="
-      env_var_list_separator:
-        type: string
-        description: "Separator between environment variable pairs."
-        default: ","
+        description: "Environment variables for jobs as JSON (e.g., '{\"DEBUG\":\"1\",\"LOG_LEVEL\":\"info\"}')."
+        default: "{}"
 
 jobs:
   construct-matrix:
@@ -29,8 +21,14 @@ jobs:
           persist-credentials: false
       - id: generate-matrix
         run: |
-          # Parse environment variables using the parse_env_vars script
-          env_vars_json=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/parse_env_vars.sh | ENV_VARS="$MATRIX_ENV_VARS" ENV_VAR_PAIR_SEPARATOR="$MATRIX_ENV_VAR_PAIR_SEPARATOR" ENV_VAR_LIST_SEPARATOR="$MATRIX_ENV_VAR_LIST_SEPARATOR" bash)
+          # Validate and use JSON environment variables directly
+          env_vars_json='${{ inputs.env_vars }}'
+
+          # Validate JSON format
+          if ! echo "$env_vars_json" | jq empty 2>/dev/null; then
+            echo "Error: env_vars is not valid JSON"
+            exit 1
+          fi
 
           # Generate matrix with parsed environment variables
           cat >> "$GITHUB_OUTPUT" << EOM
@@ -62,9 +60,6 @@ jobs:
           }' | jq -c)
           EOM
         env:
-          MATRIX_ENV_VARS: ${{ inputs.env_vars }}
-          MATRIX_ENV_VAR_PAIR_SEPARATOR: ${{ inputs.env_var_pair_separator }}
-          MATRIX_ENV_VAR_LIST_SEPARATOR: ${{ inputs.env_var_list_separator }}
 
   static-sdk:
     name: Static SDK
diff --git a/.github/workflows/unit_tests.yml b/.github/workflows/unit_tests.yml
index 6356fc1145..e9874b6e49 100644
--- a/.github/workflows/unit_tests.yml
+++ b/.github/workflows/unit_tests.yml
@@ -135,28 +135,12 @@ on:
 
       linux_env_vars:
         type: string
-        description: "Environment variables for Linux jobs (e.g., 'DEBUG=1,LOG_LEVEL=info')."
-        default: ""
-      linux_env_var_pair_separator:
-        type: string
-        description: "Separator between key and value for Linux environment variables."
-        default: "="
-      linux_env_var_list_separator:
-        type: string
-        description: "Separator between environment variable pairs for Linux."
-        default: ","
+        description: "Environment variables for Linux jobs as JSON (e.g., '{\"DEBUG\":\"1\",\"LOG_LEVEL\":\"info\"}')."
+        default: "{}"
       windows_env_vars:
         type: string
-        description: "Environment variables for Windows jobs (e.g., 'DEBUG=1,LOG_LEVEL=info')."
-        default: ""
-      windows_env_var_pair_separator:
-        type: string
-        description: "Separator between key and value for Windows environment variables."
-        default: "="
-      windows_env_var_list_separator:
-        type: string
-        description: "Separator between environment variable pairs for Windows."
-        default: ","
+        description: "Environment variables for Windows jobs as JSON (e.g., '{\"DEBUG\":\"1\",\"LOG_LEVEL\":\"info\"}')."
+        default: "{}"
 
 jobs:
   construct-matrix:
@@ -171,11 +155,20 @@ jobs:
           persist-credentials: false
       - id: generate-matrix
         run: |
-          # Parse Linux environment variables
-          linux_env_vars_json=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/parse_env_vars.sh | ENV_VARS="${{ inputs.linux_env_vars }}" ENV_VAR_PAIR_SEPARATOR="${{ inputs.linux_env_var_pair_separator }}" ENV_VAR_LIST_SEPARATOR="${{ inputs.linux_env_var_list_separator }}" bash)
+          # Validate and use JSON environment variables directly
+          linux_env_vars_json='${{ inputs.linux_env_vars }}'
+          windows_env_vars_json='${{ inputs.windows_env_vars }}'
+
+          # Validate JSON format
+          if ! echo "$linux_env_vars_json" | jq empty 2>/dev/null; then
+            echo "Error: linux_env_vars is not valid JSON"
+            exit 1
+          fi
 
-          # Parse Windows environment variables
-          windows_env_vars_json=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/parse_env_vars.sh | ENV_VARS="${{ inputs.windows_env_vars }}" ENV_VAR_PAIR_SEPARATOR="${{ inputs.windows_env_var_pair_separator }}" ENV_VAR_LIST_SEPARATOR="${{ inputs.windows_env_var_list_separator }}" bash)
+          if ! echo "$windows_env_vars_json" | jq empty 2>/dev/null; then
+            echo "Error: windows_env_vars is not valid JSON"
+            exit 1
+          fi
 
           # Generate matrix
           echo "unit-test-matrix=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/generate_matrix.sh | MATRIX_LINUX_ENV_VARS_JSON="${linux_env_vars_json}" MATRIX_WINDOWS_ENV_VARS_JSON="${windows_env_vars_json}" bash)" >> "$GITHUB_OUTPUT"
diff --git a/scripts/parse_env_vars.sh b/scripts/parse_env_vars.sh
deleted file mode 100755
index 1e48fa28e7..0000000000
--- a/scripts/parse_env_vars.sh
+++ /dev/null
@@ -1,51 +0,0 @@
-#!/bin/bash
-##===----------------------------------------------------------------------===##
-##
-## This source file is part of the SwiftNIO open source project
-##
-## Copyright (c) 2025 Apple Inc. and the SwiftNIO project authors
-## Licensed under Apache License v2.0
-##
-## See LICENSE.txt for license information
-## See CONTRIBUTORS.txt for the list of SwiftNIO project authors
-##
-## SPDX-License-Identifier: Apache-2.0
-##
-##===----------------------------------------------------------------------===##
-
-env_vars="${ENV_VARS:=""}"
-env_var_pair_separator="${ENV_VAR_PAIR_SEPARATOR:="="}"
-env_var_list_separator="${ENV_VAR_LIST_SEPARATOR:=","}"
-
-# Function to parse environment variables and convert to JSON object
-parse_env_vars() {
-  local env_vars="$1"
-  local pair_separator="$2"
-  local list_separator="$3"
-
-  if [[ -z "$env_vars" ]]; then
-    echo "{}"
-    return
-  fi
-
-  local json_obj="{}"
-
-  # Split the env_vars string by list_separator
-  IFS="$list_separator" read -ra env_pairs <<< "$env_vars"
-
-  for pair in "${env_pairs[@]}"; do
-    # Split each pair by pair_separator
-    IFS="$pair_separator" read -ra kv <<< "$pair"
-    if [[ ${#kv[@]} -eq 2 ]]; then
-      local key="${kv[0]}"
-      local value="${kv[1]}"
-      # Add to JSON object using jq
-      json_obj=$(echo "$json_obj" | jq -c --arg key "$key" --arg value "$value" '. + {($key): $value}')
-    fi
-  done
-
-  echo "$json_obj"
-}
-
-# Execute the function with the environment variables
-parse_env_vars "$env_vars" "$env_var_pair_separator" "$env_var_list_separator"

From 2c3c5ff893147ba6b2f755321556a33c1a207dc1 Mon Sep 17 00:00:00 2001
From: Rick Newton-Rogers <rnro@apple.com>
Date: Mon, 22 Sep 2025 14:46:39 +0100
Subject: [PATCH 25/27] testing

---
 .github/workflows/benchmarks.yml             |  6 +++---
 .github/workflows/cmake_tests.yml            |  4 ++--
 .github/workflows/cxx_interop.yml            |  6 +++---
 .github/workflows/main.yml                   | 18 +++++++++---------
 .github/workflows/pull_request.yml           | 19 ++++++++++---------
 .github/workflows/release_builds.yml         |  4 ++--
 .github/workflows/static_sdk.yml             |  6 +++---
 .github/workflows/swift_load_test_matrix.yml |  2 +-
 .github/workflows/swift_matrix.yml           |  2 +-
 .github/workflows/unit_tests.yml             |  4 ++--
 10 files changed, 36 insertions(+), 35 deletions(-)

diff --git a/.github/workflows/benchmarks.yml b/.github/workflows/benchmarks.yml
index 31605140f0..e88b4e7cf8 100644
--- a/.github/workflows/benchmarks.yml
+++ b/.github/workflows/benchmarks.yml
@@ -94,9 +94,9 @@ jobs:
             exit 1
           fi
 
-          echo "benchmarks-matrix=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/generate_matrix.sh | MATRIX_LINUX_ENV_VARS_JSON="${linux_env_vars_json}" bash)" >> "$GITHUB_OUTPUT"
+          echo "benchmarks-matrix=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/matrix_custom_env_vars/scripts/generate_matrix.sh | MATRIX_LINUX_ENV_VARS_JSON="${linux_env_vars_json}" bash)" >> "$GITHUB_OUTPUT"
         env:
-          MATRIX_LINUX_COMMAND: "curl -s https://raw.githubusercontent.com/apple/swift-nio/main/scripts/check_benchmark_thresholds.sh | BENCHMARK_PACKAGE_PATH=${{ inputs.benchmark_package_path }} bash"
+          MATRIX_LINUX_COMMAND: "curl -s https://raw.githubusercontent.com/apple/swift-nio/matrix_custom_env_vars/scripts/check_benchmark_thresholds.sh | BENCHMARK_PACKAGE_PATH=${{ inputs.benchmark_package_path }} bash"
           MATRIX_LINUX_SETUP_COMMAND: "swift --version && apt-get update -y -q && apt-get install -y -q curl libjemalloc-dev && git config --global --add safe.directory /$(basename ${{ github.workspace }})"
           MATRIX_LINUX_5_9_ENABLED: ${{ inputs.linux_5_9_enabled }}
           MATRIX_LINUX_5_10_ENABLED: ${{ inputs.linux_5_10_enabled }}
@@ -110,7 +110,7 @@ jobs:
     name: Benchmarks
     needs: construct-matrix
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@main
+    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@matrix_custom_env_vars
     with:
       name: "Benchmarks"
       matrix_string: '${{ needs.construct-matrix.outputs.benchmarks-matrix }}'
diff --git a/.github/workflows/cmake_tests.yml b/.github/workflows/cmake_tests.yml
index ec6100cf64..5cd99069f9 100644
--- a/.github/workflows/cmake_tests.yml
+++ b/.github/workflows/cmake_tests.yml
@@ -40,11 +40,11 @@ jobs:
           which curl jq || apt -q update
           which curl || apt -yq install curl
           which jq || apt -yq install jq
-          curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/update-cmake-lists.sh | CONFIG_JSON='${{ inputs.update_cmake_lists_config }}' FAIL_ON_CHANGES=true bash
+          curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/matrix_custom_env_vars/scripts/update-cmake-lists.sh | CONFIG_JSON='${{ inputs.update_cmake_lists_config }}' FAIL_ON_CHANGES=true bash
       - name: CMake build
         run: |
           which curl cmake ninja || apt -q update
           which curl || apt -yq install curl
           which cmake || apt -yq install cmake
           which ninja || apt -yq install ninja-build
-          curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/cmake-build.sh | TARGET_DIRECTORY="${{ inputs.cmake_build_target_directory }}" CMAKE_VERSION="${{ inputs.cmake_version }}" bash
+          curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/matrix_custom_env_vars/scripts/cmake-build.sh | TARGET_DIRECTORY="${{ inputs.cmake_build_target_directory }}" CMAKE_VERSION="${{ inputs.cmake_version }}" bash
diff --git a/.github/workflows/cxx_interop.yml b/.github/workflows/cxx_interop.yml
index 5076619e23..58cb302426 100644
--- a/.github/workflows/cxx_interop.yml
+++ b/.github/workflows/cxx_interop.yml
@@ -97,9 +97,9 @@ jobs:
             exit 1
           fi
 
-          echo "cxx-interop-matrix=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/generate_matrix.sh | MATRIX_LINUX_ENV_VARS_JSON="${linux_env_vars_json}" MATRIX_WINDOWS_ENV_VARS_JSON="${windows_env_vars_json}" bash)" >> "$GITHUB_OUTPUT"
+          echo "cxx-interop-matrix=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/matrix_custom_env_vars/scripts/generate_matrix.sh | MATRIX_LINUX_ENV_VARS_JSON="${linux_env_vars_json}" MATRIX_WINDOWS_ENV_VARS_JSON="${windows_env_vars_json}" bash)" >> "$GITHUB_OUTPUT"
         env:
-          MATRIX_LINUX_COMMAND: "curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/check-cxx-interop-compatibility.sh | bash"
+          MATRIX_LINUX_COMMAND: "curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/matrix_custom_env_vars/scripts/check-cxx-interop-compatibility.sh | bash"
           MATRIX_LINUX_SETUP_COMMAND: "swift --version && apt-get update -y -q && apt-get install -y -q curl jq"
           MATRIX_LINUX_5_9_ENABLED: ${{ inputs.linux_5_9_enabled }}
           MATRIX_LINUX_5_10_ENABLED: ${{ inputs.linux_5_10_enabled }}
@@ -113,7 +113,7 @@ jobs:
     name: Cxx interop
     needs: construct-matrix
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@main
+    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@matrix_custom_env_vars
     with:
       name: "Cxx interop"
       matrix_string: '${{ needs.construct-matrix.outputs.cxx-interop-matrix }}'
diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 5178bcce81..17a9f44b2e 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -10,7 +10,7 @@ jobs:
   unit-tests:
     name: Unit tests
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/unit_tests.yml@main
+    uses: apple/swift-nio/.github/workflows/unit_tests.yml@matrix_custom_env_vars
     with:
       linux_5_10_arguments_override: "-Xswiftc -warnings-as-errors --explicit-target-dependency-import-check error"
       linux_6_0_arguments_override: "-Xswiftc -warnings-as-errors --explicit-target-dependency-import-check error"
@@ -22,12 +22,12 @@ jobs:
   cxx-interop:
     name: Cxx interop
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/cxx_interop.yml@main
+    uses: apple/swift-nio/.github/workflows/cxx_interop.yml@matrix_custom_env_vars
 
   benchmarks:
     name: Benchmarks
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/benchmarks.yml@main
+    uses: apple/swift-nio/.github/workflows/benchmarks.yml@matrix_custom_env_vars
     with:
       benchmark_package_path: "Benchmarks"
 
@@ -42,7 +42,7 @@ jobs:
         with:
           persist-credentials: false
       - id: generate-matrix
-        run: echo "integration-test-matrix=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/generate_matrix.sh | bash)" >> "$GITHUB_OUTPUT"
+        run: echo "integration-test-matrix=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/matrix_custom_env_vars/scripts/generate_matrix.sh | bash)" >> "$GITHUB_OUTPUT"
         env:
           MATRIX_LINUX_SETUP_COMMAND: "apt-get update -y -q && apt-get install -y -q lsof dnsutils netcat-openbsd net-tools curl jq"
           MATRIX_LINUX_COMMAND: "./scripts/integration_tests.sh"
@@ -51,7 +51,7 @@ jobs:
     name: Integration tests
     needs: construct-integration-test-matrix
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@main
+    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@matrix_custom_env_vars
     with:
       name: "Integration tests"
       matrix_string: '${{ needs.construct-integration-test-matrix.outputs.integration-test-matrix }}'
@@ -59,17 +59,17 @@ jobs:
   static-sdk:
     name: Static Linux Swift SDK
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/static_sdk.yml@main
+    uses: apple/swift-nio/.github/workflows/static_sdk.yml@matrix_custom_env_vars
 
   wasm-sdk:
     name: WebAssembly Swift SDK
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/wasm_sdk.yml@main
+    uses: apple/swift-nio/.github/workflows/wasm_sdk.yml@matrix_custom_env_vars
 
   macos-tests:
     name: macOS tests
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/macos_tests.yml@main
+    uses: apple/swift-nio/.github/workflows/macos_tests.yml@matrix_custom_env_vars
     with:
       runner_pool: nightly
       build_scheme: swift-nio-Package
@@ -83,4 +83,4 @@ jobs:
 
   release-builds:
     name: Release builds
-    uses: apple/swift-nio/.github/workflows/release_builds.yml@main
+    uses: apple/swift-nio/.github/workflows/release_builds.yml@matrix_custom_env_vars
diff --git a/.github/workflows/pull_request.yml b/.github/workflows/pull_request.yml
index f171e1de5b..634bdd0389 100644
--- a/.github/workflows/pull_request.yml
+++ b/.github/workflows/pull_request.yml
@@ -14,8 +14,9 @@ jobs:
   unit-tests:
     name: Unit tests
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/unit_tests.yml@main
+    uses: apple/swift-nio/.github/workflows/unit_tests.yml@matrix_custom_env_vars
     with:
+      linux_env_vars: '{"TEST_DEBUG":"1","TEST_LOG_LEVEL":"info"}'
       linux_5_10_arguments_override: "-Xswiftc -warnings-as-errors --explicit-target-dependency-import-check error"
       linux_6_0_arguments_override: "-Xswiftc -warnings-as-errors --explicit-target-dependency-import-check error"
       linux_6_1_arguments_override: "-Xswiftc -warnings-as-errors --explicit-target-dependency-import-check error"
@@ -26,14 +27,14 @@ jobs:
   benchmarks:
     name: Benchmarks
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/benchmarks.yml@main
+    uses: apple/swift-nio/.github/workflows/benchmarks.yml@matrix_custom_env_vars
     with:
       benchmark_package_path: "Benchmarks"
 
   cxx-interop:
     name: Cxx interop
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/cxx_interop.yml@main
+    uses: apple/swift-nio/.github/workflows/cxx_interop.yml@matrix_custom_env_vars
 
   construct-integration-test-matrix:
     name: Construct integration test matrix
@@ -46,7 +47,7 @@ jobs:
         with:
           persist-credentials: false
       - id: generate-matrix
-        run: echo "integration-test-matrix=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/generate_matrix.sh | bash)" >> "$GITHUB_OUTPUT"
+        run: echo "integration-test-matrix=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/matrix_custom_env_vars/scripts/generate_matrix.sh | bash)" >> "$GITHUB_OUTPUT"
         env:
           MATRIX_LINUX_SETUP_COMMAND: "apt-get update -y -q && apt-get install -y -q lsof dnsutils netcat-openbsd net-tools curl jq"
           MATRIX_LINUX_COMMAND: "./scripts/integration_tests.sh"
@@ -55,7 +56,7 @@ jobs:
     name: Integration tests
     needs: construct-integration-test-matrix
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@main
+    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@matrix_custom_env_vars
     with:
       name: "Integration tests"
       matrix_string: '${{ needs.construct-integration-test-matrix.outputs.integration-test-matrix }}'
@@ -81,7 +82,7 @@ jobs:
   macos-tests:
     name: macOS tests
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/macos_tests.yml@main
+    uses: apple/swift-nio/.github/workflows/macos_tests.yml@matrix_custom_env_vars
     with:
       runner_pool: general
       build_scheme: swift-nio-Package
@@ -91,13 +92,13 @@ jobs:
   static-sdk:
     name: Static Linux Swift SDK
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/static_sdk.yml@main
+    uses: apple/swift-nio/.github/workflows/static_sdk.yml@matrix_custom_env_vars
 
   wasm-sdk:
     name: WebAssembly Swift SDK
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/wasm_sdk.yml@main
+    uses: apple/swift-nio/.github/workflows/wasm_sdk.yml@matrix_custom_env_vars
 
   release-builds:
     name: Release builds
-    uses: apple/swift-nio/.github/workflows/release_builds.yml@main
+    uses: apple/swift-nio/.github/workflows/release_builds.yml@matrix_custom_env_vars
diff --git a/.github/workflows/release_builds.yml b/.github/workflows/release_builds.yml
index 6c605b5679..8a6be1f82d 100644
--- a/.github/workflows/release_builds.yml
+++ b/.github/workflows/release_builds.yml
@@ -129,7 +129,7 @@ jobs:
             exit 1
           fi
 
-          echo "release-build-matrix=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/generate_matrix.sh | MATRIX_LINUX_ENV_VARS_JSON="${linux_env_vars_json}" MATRIX_WINDOWS_ENV_VARS_JSON="${windows_env_vars_json}" bash)" >> "$GITHUB_OUTPUT"
+          echo "release-build-matrix=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/matrix_custom_env_vars/scripts/generate_matrix.sh | MATRIX_LINUX_ENV_VARS_JSON="${linux_env_vars_json}" MATRIX_WINDOWS_ENV_VARS_JSON="${windows_env_vars_json}" bash)" >> "$GITHUB_OUTPUT"
         env:
           MATRIX_LINUX_SETUP_COMMAND: "swift --version"
           MATRIX_LINUX_COMMAND: "swift build -c release"
@@ -161,7 +161,7 @@ jobs:
     name: Release builds
     needs: construct-matrix
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@main
+    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@matrix_custom_env_vars
     with:
       name: "Release builds"
       matrix_string: '${{ needs.construct-matrix.outputs.release-build-matrix }}'
diff --git a/.github/workflows/static_sdk.yml b/.github/workflows/static_sdk.yml
index bbd32caec4..8d4c0006f5 100644
--- a/.github/workflows/static_sdk.yml
+++ b/.github/workflows/static_sdk.yml
@@ -40,7 +40,7 @@ jobs:
                 "platform":"Linux",
                 "runner":"ubuntu-latest",
                 "image":"ubuntu:jammy",
-                "setup_command":"apt update -q && apt install -y -q curl jq tar && curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/install_swift_prerequisites.sh | bash && curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/install_static_sdk.sh | INSTALL_SWIFT_STATIC_SDK_VERSION=latest INSTALL_SWIFT_STATIC_SDK_ARCH=x86_64 bash && hash -r",
+                "setup_command":"apt update -q && apt install -y -q curl jq tar && curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/matrix_custom_env_vars/scripts/install_swift_prerequisites.sh | bash && curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/install_static_sdk.sh | INSTALL_SWIFT_STATIC_SDK_VERSION=latest INSTALL_SWIFT_STATIC_SDK_ARCH=x86_64 bash && hash -r",
                 "command":"swift build",
                 "command_arguments":"--swift-sdk x86_64-swift-linux-musl",
                 "env":'"$env_vars_json"'
@@ -51,7 +51,7 @@ jobs:
                 "platform":"Linux",
                 "runner":"ubuntu-latest",
                 "image":"ubuntu:jammy",
-                "setup_command":"apt update -q && apt install -y -q curl jq tar && curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/install_swift_prerequisites.sh | bash && curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/install_static_sdk.sh | INSTALL_SWIFT_STATIC_SDK_BRANCH=main INSTALL_SWIFT_STATIC_SDK_ARCH=x86_64 bash && hash -r",
+                "setup_command":"apt update -q && apt install -y -q curl jq tar && curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/matrix_custom_env_vars/scripts/install_swift_prerequisites.sh | bash && curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/install_static_sdk.sh | INSTALL_SWIFT_STATIC_SDK_BRANCH=main INSTALL_SWIFT_STATIC_SDK_ARCH=x86_64 bash && hash -r",
                 "command":"swift build",
                 "command_arguments":"--swift-sdk x86_64-swift-linux-musl",
                 "env":'"$env_vars_json"'
@@ -65,7 +65,7 @@ jobs:
     name: Static SDK
     needs: construct-matrix
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@main
+    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@matrix_custom_env_vars
     with:
       name: "Static SDK"
       matrix_string: '${{ needs.construct-matrix.outputs.static-sdk-matrix }}'
diff --git a/.github/workflows/swift_load_test_matrix.yml b/.github/workflows/swift_load_test_matrix.yml
index 9b7b53b7f2..12b2df5c12 100644
--- a/.github/workflows/swift_load_test_matrix.yml
+++ b/.github/workflows/swift_load_test_matrix.yml
@@ -35,7 +35,7 @@ jobs:
     name: Execute matrix
     needs: load-matrix
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@main
+    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@matrix_custom_env_vars
     with:
       name: ${{ inputs.name }}
       matrix_string: '${{ needs.load-matrix.outputs.swift-matrix }}'
diff --git a/.github/workflows/swift_matrix.yml b/.github/workflows/swift_matrix.yml
index 90cade7613..7dbf561c51 100644
--- a/.github/workflows/swift_matrix.yml
+++ b/.github/workflows/swift_matrix.yml
@@ -165,7 +165,7 @@ jobs:
           COMMAND_OVERRIDE_NIGHTLY_MAIN: ${{ inputs.matrix_linux_nightly_main_command_override }}
         run: |
           apt-get -qq update && apt-get -qq -y install curl
-          curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/check-matrix-job.sh | bash
+          curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/matrix_custom_env_vars/scripts/check-matrix-job.sh | bash
 
   windows:
     name: Windows (${{ matrix.swift.swift_version }})
diff --git a/.github/workflows/unit_tests.yml b/.github/workflows/unit_tests.yml
index e9874b6e49..09fd52b766 100644
--- a/.github/workflows/unit_tests.yml
+++ b/.github/workflows/unit_tests.yml
@@ -171,7 +171,7 @@ jobs:
           fi
 
           # Generate matrix
-          echo "unit-test-matrix=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/generate_matrix.sh | MATRIX_LINUX_ENV_VARS_JSON="${linux_env_vars_json}" MATRIX_WINDOWS_ENV_VARS_JSON="${windows_env_vars_json}" bash)" >> "$GITHUB_OUTPUT"
+          echo "unit-test-matrix=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/matrix_custom_env_vars/scripts/generate_matrix.sh | MATRIX_LINUX_ENV_VARS_JSON="${linux_env_vars_json}" MATRIX_WINDOWS_ENV_VARS_JSON="${windows_env_vars_json}" bash)" >> "$GITHUB_OUTPUT"
         env:
           MATRIX_LINUX_SETUP_COMMAND: "swift --version"
           MATRIX_LINUX_COMMAND: "swift test"
@@ -205,7 +205,7 @@ jobs:
     name: Unit tests
     needs: construct-matrix
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@main
+    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@matrix_custom_env_vars
     with:
       name: "Unit tests"
       matrix_string: '${{ needs.construct-matrix.outputs.unit-test-matrix }}'

From 2aec72d29639570b6eb5e1a32b1a8a5917674fa9 Mon Sep 17 00:00:00 2001
From: Rick Newton-Rogers <rnro@apple.com>
Date: Mon, 22 Sep 2025 14:55:21 +0100
Subject: [PATCH 26/27] static sdk env

---
 .github/workflows/static_sdk.yml | 1 -
 1 file changed, 1 deletion(-)

diff --git a/.github/workflows/static_sdk.yml b/.github/workflows/static_sdk.yml
index 8d4c0006f5..96e57e3e34 100644
--- a/.github/workflows/static_sdk.yml
+++ b/.github/workflows/static_sdk.yml
@@ -59,7 +59,6 @@ jobs:
             ]
           }' | jq -c)
           EOM
-        env:
 
   static-sdk:
     name: Static SDK

From 98ed95681208524751772e6a2b335340a94429ec Mon Sep 17 00:00:00 2001
From: Rick Newton-Rogers <rnro@apple.com>
Date: Mon, 22 Sep 2025 15:04:01 +0100
Subject: [PATCH 27/27] Revert "testing"

This reverts commit 2c3c5ff893147ba6b2f755321556a33c1a207dc1.
---
 .github/workflows/benchmarks.yml             |  6 +++---
 .github/workflows/cmake_tests.yml            |  4 ++--
 .github/workflows/cxx_interop.yml            |  6 +++---
 .github/workflows/main.yml                   | 18 +++++++++---------
 .github/workflows/pull_request.yml           | 19 +++++++++----------
 .github/workflows/release_builds.yml         |  4 ++--
 .github/workflows/static_sdk.yml             |  6 +++---
 .github/workflows/swift_load_test_matrix.yml |  2 +-
 .github/workflows/swift_matrix.yml           |  2 +-
 .github/workflows/unit_tests.yml             |  4 ++--
 10 files changed, 35 insertions(+), 36 deletions(-)

diff --git a/.github/workflows/benchmarks.yml b/.github/workflows/benchmarks.yml
index e88b4e7cf8..31605140f0 100644
--- a/.github/workflows/benchmarks.yml
+++ b/.github/workflows/benchmarks.yml
@@ -94,9 +94,9 @@ jobs:
             exit 1
           fi
 
-          echo "benchmarks-matrix=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/matrix_custom_env_vars/scripts/generate_matrix.sh | MATRIX_LINUX_ENV_VARS_JSON="${linux_env_vars_json}" bash)" >> "$GITHUB_OUTPUT"
+          echo "benchmarks-matrix=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/generate_matrix.sh | MATRIX_LINUX_ENV_VARS_JSON="${linux_env_vars_json}" bash)" >> "$GITHUB_OUTPUT"
         env:
-          MATRIX_LINUX_COMMAND: "curl -s https://raw.githubusercontent.com/apple/swift-nio/matrix_custom_env_vars/scripts/check_benchmark_thresholds.sh | BENCHMARK_PACKAGE_PATH=${{ inputs.benchmark_package_path }} bash"
+          MATRIX_LINUX_COMMAND: "curl -s https://raw.githubusercontent.com/apple/swift-nio/main/scripts/check_benchmark_thresholds.sh | BENCHMARK_PACKAGE_PATH=${{ inputs.benchmark_package_path }} bash"
           MATRIX_LINUX_SETUP_COMMAND: "swift --version && apt-get update -y -q && apt-get install -y -q curl libjemalloc-dev && git config --global --add safe.directory /$(basename ${{ github.workspace }})"
           MATRIX_LINUX_5_9_ENABLED: ${{ inputs.linux_5_9_enabled }}
           MATRIX_LINUX_5_10_ENABLED: ${{ inputs.linux_5_10_enabled }}
@@ -110,7 +110,7 @@ jobs:
     name: Benchmarks
     needs: construct-matrix
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@matrix_custom_env_vars
+    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@main
     with:
       name: "Benchmarks"
       matrix_string: '${{ needs.construct-matrix.outputs.benchmarks-matrix }}'
diff --git a/.github/workflows/cmake_tests.yml b/.github/workflows/cmake_tests.yml
index 5cd99069f9..ec6100cf64 100644
--- a/.github/workflows/cmake_tests.yml
+++ b/.github/workflows/cmake_tests.yml
@@ -40,11 +40,11 @@ jobs:
           which curl jq || apt -q update
           which curl || apt -yq install curl
           which jq || apt -yq install jq
-          curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/matrix_custom_env_vars/scripts/update-cmake-lists.sh | CONFIG_JSON='${{ inputs.update_cmake_lists_config }}' FAIL_ON_CHANGES=true bash
+          curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/update-cmake-lists.sh | CONFIG_JSON='${{ inputs.update_cmake_lists_config }}' FAIL_ON_CHANGES=true bash
       - name: CMake build
         run: |
           which curl cmake ninja || apt -q update
           which curl || apt -yq install curl
           which cmake || apt -yq install cmake
           which ninja || apt -yq install ninja-build
-          curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/matrix_custom_env_vars/scripts/cmake-build.sh | TARGET_DIRECTORY="${{ inputs.cmake_build_target_directory }}" CMAKE_VERSION="${{ inputs.cmake_version }}" bash
+          curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/cmake-build.sh | TARGET_DIRECTORY="${{ inputs.cmake_build_target_directory }}" CMAKE_VERSION="${{ inputs.cmake_version }}" bash
diff --git a/.github/workflows/cxx_interop.yml b/.github/workflows/cxx_interop.yml
index 58cb302426..5076619e23 100644
--- a/.github/workflows/cxx_interop.yml
+++ b/.github/workflows/cxx_interop.yml
@@ -97,9 +97,9 @@ jobs:
             exit 1
           fi
 
-          echo "cxx-interop-matrix=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/matrix_custom_env_vars/scripts/generate_matrix.sh | MATRIX_LINUX_ENV_VARS_JSON="${linux_env_vars_json}" MATRIX_WINDOWS_ENV_VARS_JSON="${windows_env_vars_json}" bash)" >> "$GITHUB_OUTPUT"
+          echo "cxx-interop-matrix=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/generate_matrix.sh | MATRIX_LINUX_ENV_VARS_JSON="${linux_env_vars_json}" MATRIX_WINDOWS_ENV_VARS_JSON="${windows_env_vars_json}" bash)" >> "$GITHUB_OUTPUT"
         env:
-          MATRIX_LINUX_COMMAND: "curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/matrix_custom_env_vars/scripts/check-cxx-interop-compatibility.sh | bash"
+          MATRIX_LINUX_COMMAND: "curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/check-cxx-interop-compatibility.sh | bash"
           MATRIX_LINUX_SETUP_COMMAND: "swift --version && apt-get update -y -q && apt-get install -y -q curl jq"
           MATRIX_LINUX_5_9_ENABLED: ${{ inputs.linux_5_9_enabled }}
           MATRIX_LINUX_5_10_ENABLED: ${{ inputs.linux_5_10_enabled }}
@@ -113,7 +113,7 @@ jobs:
     name: Cxx interop
     needs: construct-matrix
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@matrix_custom_env_vars
+    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@main
     with:
       name: "Cxx interop"
       matrix_string: '${{ needs.construct-matrix.outputs.cxx-interop-matrix }}'
diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 17a9f44b2e..5178bcce81 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -10,7 +10,7 @@ jobs:
   unit-tests:
     name: Unit tests
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/unit_tests.yml@matrix_custom_env_vars
+    uses: apple/swift-nio/.github/workflows/unit_tests.yml@main
     with:
       linux_5_10_arguments_override: "-Xswiftc -warnings-as-errors --explicit-target-dependency-import-check error"
       linux_6_0_arguments_override: "-Xswiftc -warnings-as-errors --explicit-target-dependency-import-check error"
@@ -22,12 +22,12 @@ jobs:
   cxx-interop:
     name: Cxx interop
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/cxx_interop.yml@matrix_custom_env_vars
+    uses: apple/swift-nio/.github/workflows/cxx_interop.yml@main
 
   benchmarks:
     name: Benchmarks
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/benchmarks.yml@matrix_custom_env_vars
+    uses: apple/swift-nio/.github/workflows/benchmarks.yml@main
     with:
       benchmark_package_path: "Benchmarks"
 
@@ -42,7 +42,7 @@ jobs:
         with:
           persist-credentials: false
       - id: generate-matrix
-        run: echo "integration-test-matrix=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/matrix_custom_env_vars/scripts/generate_matrix.sh | bash)" >> "$GITHUB_OUTPUT"
+        run: echo "integration-test-matrix=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/generate_matrix.sh | bash)" >> "$GITHUB_OUTPUT"
         env:
           MATRIX_LINUX_SETUP_COMMAND: "apt-get update -y -q && apt-get install -y -q lsof dnsutils netcat-openbsd net-tools curl jq"
           MATRIX_LINUX_COMMAND: "./scripts/integration_tests.sh"
@@ -51,7 +51,7 @@ jobs:
     name: Integration tests
     needs: construct-integration-test-matrix
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@matrix_custom_env_vars
+    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@main
     with:
       name: "Integration tests"
       matrix_string: '${{ needs.construct-integration-test-matrix.outputs.integration-test-matrix }}'
@@ -59,17 +59,17 @@ jobs:
   static-sdk:
     name: Static Linux Swift SDK
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/static_sdk.yml@matrix_custom_env_vars
+    uses: apple/swift-nio/.github/workflows/static_sdk.yml@main
 
   wasm-sdk:
     name: WebAssembly Swift SDK
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/wasm_sdk.yml@matrix_custom_env_vars
+    uses: apple/swift-nio/.github/workflows/wasm_sdk.yml@main
 
   macos-tests:
     name: macOS tests
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/macos_tests.yml@matrix_custom_env_vars
+    uses: apple/swift-nio/.github/workflows/macos_tests.yml@main
     with:
       runner_pool: nightly
       build_scheme: swift-nio-Package
@@ -83,4 +83,4 @@ jobs:
 
   release-builds:
     name: Release builds
-    uses: apple/swift-nio/.github/workflows/release_builds.yml@matrix_custom_env_vars
+    uses: apple/swift-nio/.github/workflows/release_builds.yml@main
diff --git a/.github/workflows/pull_request.yml b/.github/workflows/pull_request.yml
index 634bdd0389..f171e1de5b 100644
--- a/.github/workflows/pull_request.yml
+++ b/.github/workflows/pull_request.yml
@@ -14,9 +14,8 @@ jobs:
   unit-tests:
     name: Unit tests
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/unit_tests.yml@matrix_custom_env_vars
+    uses: apple/swift-nio/.github/workflows/unit_tests.yml@main
     with:
-      linux_env_vars: '{"TEST_DEBUG":"1","TEST_LOG_LEVEL":"info"}'
       linux_5_10_arguments_override: "-Xswiftc -warnings-as-errors --explicit-target-dependency-import-check error"
       linux_6_0_arguments_override: "-Xswiftc -warnings-as-errors --explicit-target-dependency-import-check error"
       linux_6_1_arguments_override: "-Xswiftc -warnings-as-errors --explicit-target-dependency-import-check error"
@@ -27,14 +26,14 @@ jobs:
   benchmarks:
     name: Benchmarks
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/benchmarks.yml@matrix_custom_env_vars
+    uses: apple/swift-nio/.github/workflows/benchmarks.yml@main
     with:
       benchmark_package_path: "Benchmarks"
 
   cxx-interop:
     name: Cxx interop
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/cxx_interop.yml@matrix_custom_env_vars
+    uses: apple/swift-nio/.github/workflows/cxx_interop.yml@main
 
   construct-integration-test-matrix:
     name: Construct integration test matrix
@@ -47,7 +46,7 @@ jobs:
         with:
           persist-credentials: false
       - id: generate-matrix
-        run: echo "integration-test-matrix=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/matrix_custom_env_vars/scripts/generate_matrix.sh | bash)" >> "$GITHUB_OUTPUT"
+        run: echo "integration-test-matrix=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/generate_matrix.sh | bash)" >> "$GITHUB_OUTPUT"
         env:
           MATRIX_LINUX_SETUP_COMMAND: "apt-get update -y -q && apt-get install -y -q lsof dnsutils netcat-openbsd net-tools curl jq"
           MATRIX_LINUX_COMMAND: "./scripts/integration_tests.sh"
@@ -56,7 +55,7 @@ jobs:
     name: Integration tests
     needs: construct-integration-test-matrix
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@matrix_custom_env_vars
+    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@main
     with:
       name: "Integration tests"
       matrix_string: '${{ needs.construct-integration-test-matrix.outputs.integration-test-matrix }}'
@@ -82,7 +81,7 @@ jobs:
   macos-tests:
     name: macOS tests
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/macos_tests.yml@matrix_custom_env_vars
+    uses: apple/swift-nio/.github/workflows/macos_tests.yml@main
     with:
       runner_pool: general
       build_scheme: swift-nio-Package
@@ -92,13 +91,13 @@ jobs:
   static-sdk:
     name: Static Linux Swift SDK
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/static_sdk.yml@matrix_custom_env_vars
+    uses: apple/swift-nio/.github/workflows/static_sdk.yml@main
 
   wasm-sdk:
     name: WebAssembly Swift SDK
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/wasm_sdk.yml@matrix_custom_env_vars
+    uses: apple/swift-nio/.github/workflows/wasm_sdk.yml@main
 
   release-builds:
     name: Release builds
-    uses: apple/swift-nio/.github/workflows/release_builds.yml@matrix_custom_env_vars
+    uses: apple/swift-nio/.github/workflows/release_builds.yml@main
diff --git a/.github/workflows/release_builds.yml b/.github/workflows/release_builds.yml
index 8a6be1f82d..6c605b5679 100644
--- a/.github/workflows/release_builds.yml
+++ b/.github/workflows/release_builds.yml
@@ -129,7 +129,7 @@ jobs:
             exit 1
           fi
 
-          echo "release-build-matrix=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/matrix_custom_env_vars/scripts/generate_matrix.sh | MATRIX_LINUX_ENV_VARS_JSON="${linux_env_vars_json}" MATRIX_WINDOWS_ENV_VARS_JSON="${windows_env_vars_json}" bash)" >> "$GITHUB_OUTPUT"
+          echo "release-build-matrix=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/generate_matrix.sh | MATRIX_LINUX_ENV_VARS_JSON="${linux_env_vars_json}" MATRIX_WINDOWS_ENV_VARS_JSON="${windows_env_vars_json}" bash)" >> "$GITHUB_OUTPUT"
         env:
           MATRIX_LINUX_SETUP_COMMAND: "swift --version"
           MATRIX_LINUX_COMMAND: "swift build -c release"
@@ -161,7 +161,7 @@ jobs:
     name: Release builds
     needs: construct-matrix
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@matrix_custom_env_vars
+    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@main
     with:
       name: "Release builds"
       matrix_string: '${{ needs.construct-matrix.outputs.release-build-matrix }}'
diff --git a/.github/workflows/static_sdk.yml b/.github/workflows/static_sdk.yml
index 96e57e3e34..cae0205f22 100644
--- a/.github/workflows/static_sdk.yml
+++ b/.github/workflows/static_sdk.yml
@@ -40,7 +40,7 @@ jobs:
                 "platform":"Linux",
                 "runner":"ubuntu-latest",
                 "image":"ubuntu:jammy",
-                "setup_command":"apt update -q && apt install -y -q curl jq tar && curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/matrix_custom_env_vars/scripts/install_swift_prerequisites.sh | bash && curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/install_static_sdk.sh | INSTALL_SWIFT_STATIC_SDK_VERSION=latest INSTALL_SWIFT_STATIC_SDK_ARCH=x86_64 bash && hash -r",
+                "setup_command":"apt update -q && apt install -y -q curl jq tar && curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/install_swift_prerequisites.sh | bash && curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/install_static_sdk.sh | INSTALL_SWIFT_STATIC_SDK_VERSION=latest INSTALL_SWIFT_STATIC_SDK_ARCH=x86_64 bash && hash -r",
                 "command":"swift build",
                 "command_arguments":"--swift-sdk x86_64-swift-linux-musl",
                 "env":'"$env_vars_json"'
@@ -51,7 +51,7 @@ jobs:
                 "platform":"Linux",
                 "runner":"ubuntu-latest",
                 "image":"ubuntu:jammy",
-                "setup_command":"apt update -q && apt install -y -q curl jq tar && curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/matrix_custom_env_vars/scripts/install_swift_prerequisites.sh | bash && curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/install_static_sdk.sh | INSTALL_SWIFT_STATIC_SDK_BRANCH=main INSTALL_SWIFT_STATIC_SDK_ARCH=x86_64 bash && hash -r",
+                "setup_command":"apt update -q && apt install -y -q curl jq tar && curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/install_swift_prerequisites.sh | bash && curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/install_static_sdk.sh | INSTALL_SWIFT_STATIC_SDK_BRANCH=main INSTALL_SWIFT_STATIC_SDK_ARCH=x86_64 bash && hash -r",
                 "command":"swift build",
                 "command_arguments":"--swift-sdk x86_64-swift-linux-musl",
                 "env":'"$env_vars_json"'
@@ -64,7 +64,7 @@ jobs:
     name: Static SDK
     needs: construct-matrix
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@matrix_custom_env_vars
+    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@main
     with:
       name: "Static SDK"
       matrix_string: '${{ needs.construct-matrix.outputs.static-sdk-matrix }}'
diff --git a/.github/workflows/swift_load_test_matrix.yml b/.github/workflows/swift_load_test_matrix.yml
index 12b2df5c12..9b7b53b7f2 100644
--- a/.github/workflows/swift_load_test_matrix.yml
+++ b/.github/workflows/swift_load_test_matrix.yml
@@ -35,7 +35,7 @@ jobs:
     name: Execute matrix
     needs: load-matrix
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@matrix_custom_env_vars
+    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@main
     with:
       name: ${{ inputs.name }}
       matrix_string: '${{ needs.load-matrix.outputs.swift-matrix }}'
diff --git a/.github/workflows/swift_matrix.yml b/.github/workflows/swift_matrix.yml
index 7dbf561c51..90cade7613 100644
--- a/.github/workflows/swift_matrix.yml
+++ b/.github/workflows/swift_matrix.yml
@@ -165,7 +165,7 @@ jobs:
           COMMAND_OVERRIDE_NIGHTLY_MAIN: ${{ inputs.matrix_linux_nightly_main_command_override }}
         run: |
           apt-get -qq update && apt-get -qq -y install curl
-          curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/matrix_custom_env_vars/scripts/check-matrix-job.sh | bash
+          curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/check-matrix-job.sh | bash
 
   windows:
     name: Windows (${{ matrix.swift.swift_version }})
diff --git a/.github/workflows/unit_tests.yml b/.github/workflows/unit_tests.yml
index 09fd52b766..e9874b6e49 100644
--- a/.github/workflows/unit_tests.yml
+++ b/.github/workflows/unit_tests.yml
@@ -171,7 +171,7 @@ jobs:
           fi
 
           # Generate matrix
-          echo "unit-test-matrix=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/matrix_custom_env_vars/scripts/generate_matrix.sh | MATRIX_LINUX_ENV_VARS_JSON="${linux_env_vars_json}" MATRIX_WINDOWS_ENV_VARS_JSON="${windows_env_vars_json}" bash)" >> "$GITHUB_OUTPUT"
+          echo "unit-test-matrix=$(curl -s --retry 3 https://raw.githubusercontent.com/apple/swift-nio/main/scripts/generate_matrix.sh | MATRIX_LINUX_ENV_VARS_JSON="${linux_env_vars_json}" MATRIX_WINDOWS_ENV_VARS_JSON="${windows_env_vars_json}" bash)" >> "$GITHUB_OUTPUT"
         env:
           MATRIX_LINUX_SETUP_COMMAND: "swift --version"
           MATRIX_LINUX_COMMAND: "swift test"
@@ -205,7 +205,7 @@ jobs:
     name: Unit tests
     needs: construct-matrix
     # Workaround https://github.com/nektos/act/issues/1875
-    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@matrix_custom_env_vars
+    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@main
     with:
       name: "Unit tests"
       matrix_string: '${{ needs.construct-matrix.outputs.unit-test-matrix }}'