diff --git a/.castor/context.php b/.castor/context.php
index 22ae5dc7..eb4ab730 100644
--- a/.castor/context.php
+++ b/.castor/context.php
@@ -64,10 +64,8 @@ function create_test_context(): Context
     $c = create_default_context();
 
     return $c
-        ->withData([
-            'docker_compose_run_environment' => [
-                'APP_ENV' => 'test',
-            ],
+        ->withEnvironment([
+            'APP_ENV' => 'test',
         ])
     ;
 }
@@ -78,10 +76,8 @@ function create_ci_context(): Context
     $c = create_test_context();
 
     return $c
-        ->withData([
-            // override the default context here
-        ])
         ->withData(
+            // override the default context here
             [
                 'docker_compose_files' => [
                     'docker-compose.yml',
diff --git a/.castor/docker.php b/.castor/docker.php
index 7a5f9753..b1d940c0 100644
--- a/.castor/docker.php
+++ b/.castor/docker.php
@@ -158,7 +158,7 @@ function stop(
  * @param array<string> $params
  */
 #[AsTask(description: 'Opens a shell (bash) or proxy any command to the builder container', aliases: ['builder'])]
-function builder(#[AsRawTokens] array $params = []): void
+function builder(#[AsRawTokens] array $params = []): int
 {
     if (0 === \count($params)) {
         $params = ['bash'];
@@ -168,7 +168,8 @@ function builder(#[AsRawTokens] array $params = []): void
         ->toInteractive()
         ->withEnvironment($_ENV + $_SERVER)
     ;
-    docker_compose_run(implode(' ', $params), c: $c);
+
+    return (int) docker_compose_run(implode(' ', $params), c: $c)->getExitCode();
 }
 
 /**
@@ -388,6 +389,12 @@ function docker_compose(array $subCommand, ?Context $c = null, array $profiles =
         'REGISTRY' => $c['registry'] ?? '',
     ]);
 
+    if ($c['APP_ENV'] ?? false) {
+        $c = $c->withEnvironment([
+            'APP_ENV' => $c['APP_ENV'] ?? '',
+        ]);
+    }
+
     $command = [
         'docker',
         'compose',
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 206eba97..fce49daa 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -83,9 +83,17 @@ jobs:
                   {
                       docker_compose_run('echo "Hello World"');
                   }
+
+                  #[AsTask()]
+                  function app_env()
+                  {
+                      docker_compose_run('php public/index.php');
+                  }
                   EOPHP
 
                   castor test | grep "Hello World"
+                  CASTOR_CONTEXT=default castor app-env | grep 'Environment: not set'"
+                  CASTOR_CONTEXT=test castor app-env | grep 'Environment: test'"
 
             - name: "Test communication with DB"
               run: |
diff --git a/application/public/index.php b/application/public/index.php
index 3e184019..a881ce1c 100644
--- a/application/public/index.php
+++ b/application/public/index.php
@@ -1,3 +1,5 @@
 <?php
 
 echo 'Hello world from PHP ', \PHP_MAJOR_VERSION, '.', \PHP_MINOR_VERSION, '.', \PHP_RELEASE_VERSION, " inside Docker! \n";
+
+echo 'Environment: ', $_SERVER['APP_ENV'] ?? 'not set', "\n";
diff --git a/infrastructure/docker/docker-compose.yml b/infrastructure/docker/docker-compose.yml
index 88787178..e891adaa 100644
--- a/infrastructure/docker/docker-compose.yml
+++ b/infrastructure/docker/docker-compose.yml
@@ -5,6 +5,8 @@ x-templates:
             context: services/php
             target: worker
         user: "${USER_ID}:${USER_ID}"
+        environment:
+            - APP_ENV
         depends_on:
             postgres:
                 condition: service_healthy
@@ -41,6 +43,8 @@ services:
             cache_from:
               - "type=registry,ref=${REGISTRY:-}/frontend:cache"
         user: "${USER_ID}:${USER_ID}"
+        environment:
+            - APP_ENV
         volumes:
             - "../..:/var/www:cached"
             - "../../.home:/home/app:cached"
@@ -71,6 +75,7 @@ services:
         init: true
         user: "${USER_ID}:${USER_ID}"
         environment:
+            - APP_ENV
             # The following list contains the common environment variables exposed by CI platforms
             - GITHUB_ACTIONS
             - CI # Travis CI, CircleCI, Cirrus CI, Gitlab CI, Appveyor, CodeShip, dsari