diff --git a/bin/get-playwright-version.js b/bin/get-playwright-version.js
new file mode 100644
index 0000000..df2967f
--- /dev/null
+++ b/bin/get-playwright-version.js
@@ -0,0 +1,46 @@
+'use strict';
+
+/**
+ * Resolves the installed @playwright/test version for CI caching.
+ *
+ * Used by polylang/actions/e2e to build the Playwright browser cache key. Must be
+ * run from the consumer repository root (where npm ci has installed dependencies).
+ *
+ * Resolution order:
+ * 1. node_modules/@playwright/test/package.json (preferred — matches installed binaries)
+ * 2. package-lock.json (npm lockfile v2/v3 packages path, or legacy dependencies)
+ *
+ * @example
+ * PLAYWRIGHT_VERSION=$(node "${{ github.action_path }}/../bin/get-playwright-version.js")
+ *
+ * Output:
+ * - Prints the semver string to stdout on success.
+ * - Exits with code 1 and writes an error message to stderr when the version cannot be determined.
+ */
+
+const tryRequire = ( id ) => {
+	try {
+		return require( id );
+	} catch {
+		return null;
+	}
+};
+
+const fromPackage = tryRequire( '@playwright/test/package.json' );
+
+if ( fromPackage?.version ) {
+	process.stdout.write( fromPackage.version );
+	process.exit( 0 );
+}
+
+const lock = tryRequire( './package-lock.json' );
+const fromLock = lock?.packages?.['node_modules/@playwright/test']?.version
+	|| lock?.dependencies?.['@playwright/test']?.version
+	|| '';
+
+if ( ! fromLock ) {
+	process.stderr.write( 'Could not determine @playwright/test version.' );
+	process.exit( 1 );
+}
+
+process.stdout.write( fromLock );
diff --git a/bin/save-wp-env-docker-images.js b/bin/save-wp-env-docker-images.js
new file mode 100644
index 0000000..64e195f
--- /dev/null
+++ b/bin/save-wp-env-docker-images.js
@@ -0,0 +1,128 @@
+'use strict';
+
+/**
+ * Save wp-env Docker images to a tarball for GitHub Actions caching.
+ *
+ * Used by polylang/actions/e2e after `wp-env start`. Resolves the wp-env work
+ * directory via `wp-env status --json`, then saves images from its docker-compose.yml.
+ *
+ * @example
+ * node "${{ github.action_path }}/../bin/save-wp-env-docker-images.js"
+ * node "${{ github.action_path }}/../bin/save-wp-env-docker-images.js" --config=.wp-env.json
+ * node "${{ github.action_path }}/../bin/save-wp-env-docker-images.js" wp-env-image.tar
+ *
+ * Options:
+ * - --config=<path>  Custom wp-env config file (same as wp-env --config).
+ * - First non-flag argument: output tarball path (default: wp-env-image.tar).
+ *
+ * Output:
+ * - Writes the tarball to the output path.
+ * - Exits with code 1 when the install path or images cannot be resolved.
+ */
+
+const { execFileSync } = require( 'child_process' );
+const fs = require( 'fs' );
+const path = require( 'path' );
+
+const DEFAULT_OUTPUT = 'wp-env-image.tar';
+const COMPOSE_FILENAME = 'docker-compose.yml';
+
+/**
+ * @param {string} configPath
+ * @return {string}
+ */
+const getInstallPath = ( configPath ) => {
+	let output;
+
+	try {
+		output = execFileSync(
+			'npm',
+			[ 'run', 'wp-env', '--', 'status', '--json', ...( configPath ? [ `--config=${ configPath }` ] : [] ) ],
+			{ encoding: 'utf8' }
+		);
+	} catch {
+		process.stderr.write( 'Could not resolve wp-env install path.\n' );
+		process.exit( 1 );
+	}
+
+	let status;
+
+	try {
+		status = JSON.parse( output.trim() );
+	} catch {
+		process.stderr.write( 'Could not parse wp-env status output.\n' );
+		process.exit( 1 );
+	}
+
+	if ( ! status?.installPath ) {
+		process.stderr.write( 'wp-env status did not return an install path.\n' );
+		process.exit( 1 );
+	}
+
+	return status.installPath;
+};
+
+/**
+ * @param {string} composeFile
+ * @return {string[]}
+ */
+const getComposeImageIds = ( composeFile ) => {
+	try {
+		const output = execFileSync(
+			'docker',
+			[ 'compose', '-f', composeFile, 'images', '-q' ],
+			{ encoding: 'utf8' }
+		);
+
+		return output
+			.split( '\n' )
+			.map( ( line ) => line.trim() )
+			.filter( Boolean );
+	} catch {
+		return [];
+	}
+};
+
+/**
+ * @param {string[]} argv
+ * @return {{ configPath: string, outputTar: string }}
+ */
+const parseArgs = ( argv ) => {
+	let configPath = process.env.WP_ENV_CONFIG_PATH || '';
+	let outputTar = DEFAULT_OUTPUT;
+
+	for ( const arg of argv ) {
+		if ( arg.startsWith( '--config=' ) ) {
+			configPath = arg.slice( '--config='.length );
+			continue;
+		}
+
+		if ( ! arg.startsWith( '--' ) ) {
+			outputTar = arg;
+		}
+	}
+
+	return { configPath, outputTar };
+};
+
+const { configPath, outputTar } = parseArgs( process.argv.slice( 2 ) );
+const installPath = getInstallPath( configPath );
+const composeFile = path.join( installPath, COMPOSE_FILENAME );
+
+if ( ! fs.existsSync( composeFile ) ) {
+	process.stderr.write( `No docker-compose.yml found at ${ composeFile }.\n` );
+	process.exit( 1 );
+}
+
+const imageIds = [ ...new Set( getComposeImageIds( composeFile ) ) ];
+
+if ( imageIds.length === 0 ) {
+	process.stderr.write( 'No wp-env Docker images found to cache.\n' );
+	process.exit( 1 );
+}
+
+execFileSync(
+	'docker',
+	[ 'save', ...imageIds, '-o', outputTar ],
+	{ stdio: 'inherit' }
+ );
diff --git a/e2e/action.yml b/e2e/action.yml
index 5c1cbf5..e143a1d 100644
--- a/e2e/action.yml
+++ b/e2e/action.yml
@@ -8,6 +8,16 @@ inputs:
     required: false
     type: string
     default: 'no-external-cache-key'
+  wp-env-config-path:
+    description: Path to a custom wp-env config file passed to wp-env --config. Default is '' (wp-env default discovery).
+    required: false
+    type: string
+    default: ''
+  playwright-cmd:
+    description: CLI command to run playwright tests. Default is 'npm run test:e2e'.
+    required: false
+    type: string
+    default: 'npm run test:e2e'
 
 runs:
   using: 'composite'
@@ -18,6 +28,11 @@ runs:
       with:
         node-version: 22
 
+    - name: Get Node.js version
+      id: node-version
+      run: echo "NODE_VERSION=$(node -v)" >> "$GITHUB_OUTPUT"
+      shell: bash
+
     - name: Set up package-lock.json
       run: |
         npm install --package-lock-only --no-audit
@@ -28,7 +43,7 @@ runs:
       uses: actions/cache@v4
       with:
           path: '**/node_modules'
-          key: node_modules-${{ runner.os }}-${{ runner.arch }}-${{ steps.node-version.outputs.NODE_VERSION }}-${{ hashFiles('package-lock.json') }}
+          key: node_modules-${{ runner.os }}-${{ runner.arch }}-${{ steps.node-version.outputs.NODE_VERSION }}-${{ hashFiles('package.json', 'package-lock.json') }}
 
     - name: Install dependencies
       if: ${{ steps.cache-node_modules.outputs.cache-hit != 'true' }}
@@ -56,7 +71,8 @@ runs:
     - name: Get installed Playwright version
       id: playwright-version
       run: |
-        echo "PLAYWRIGHT_VERSION=$(node -e "console.log(require('./package-lock.json').packages['node_modules/@playwright/test'].version)")" >> $GITHUB_ENV
+        PLAYWRIGHT_VERSION=$(node "${{ github.action_path }}/../bin/get-playwright-version.js")
+        echo "PLAYWRIGHT_VERSION=$PLAYWRIGHT_VERSION" >> "$GITHUB_ENV"
       shell: bash
 
     - name: Cache Playwright binaries
@@ -66,6 +82,8 @@ runs:
         path: |
           ~/.cache/ms-playwright
         key: ${{ runner.os }}-playwright-${{ env.PLAYWRIGHT_VERSION }}
+        restore-keys: |
+          ${{ runner.os }}-playwright-
 
     - name: Install Playwright binaries
       # Only Chromium for the moment.
@@ -85,7 +103,7 @@ runs:
       uses: actions/cache@v4
       with:
         path: wp-env-image.tar
-        key: ${{ runner.os }}-wp-env-${{ env.WP_VERSION }}-${{ inputs.container-cache-key }}
+        key: ${{ runner.os }}-wp-env-${{ env.WP_VERSION }}-${{ hashFiles('.wp-env.json', '.wp-env.override.json', inputs.wp-env-config-path) }}-${{ inputs.container-cache-key }}
 
     - name: Load cached Docker image (if any)
       if: steps.docker-cache.outputs.cache-hit == 'true'
@@ -95,21 +113,25 @@ runs:
 
     - name: Install WordPress and start the server
       run: |
-        npm run wp-env start
+        if [ -n "${{ inputs.wp-env-config-path }}" ]; then
+          npm run wp-env start -- --config="${{ inputs.wp-env-config-path }}"
+        else
+          npm run wp-env start
+        fi
       shell: bash
-      env:
-        WP_ENV_PHP_VERSION: '8.0'
 
     - name: Save Docker image to cache
       if: steps.docker-cache.outputs.cache-hit != 'true'
       run: |
-        docker image ls
-        docker save $(docker images --format '{{.Repository}}:{{.Tag}}') -o wp-env-image.tar
+        if [ -n "${{ inputs.wp-env-config-path }}" ]; then
+          node "${{ github.action_path }}/../bin/save-wp-env-docker-images.js" --config="${{ inputs.wp-env-config-path }}"
+        else
+          node "${{ github.action_path }}/../bin/save-wp-env-docker-images.js"
+        fi
       shell: bash
 
-    - name: Run Playwright tests
-      run: |
-        npm run test:e2e
+    - name: Run Playwright tests with WordPress ${{ env.WP_VERSION }}
+      run: ${{ inputs.playwright-cmd }}
       shell: bash
 
     - name: Upload Playwright report