diff --git a/CHANGELOG.md b/CHANGELOG.md
index c55110d..8bb413b 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -9,6 +9,7 @@
 ### Fixed
 
 * The `pre-push` Git hook should use `./run test:commit` instead of `just test-commit` since `just` is no longer used.
+* Recursively merge `build.defaults.yaml` into the given configuration.
 
 ## 2023-11-22
 
diff --git a/src/Action/CreateFinalConfigurationData.php b/src/Action/CreateFinalConfigurationData.php
index 5d274b7..dd306d6 100644
--- a/src/Action/CreateFinalConfigurationData.php
+++ b/src/Action/CreateFinalConfigurationData.php
@@ -10,7 +10,7 @@ use Symfony\Component\Yaml\Yaml;
 final class CreateFinalConfigurationData
 {
     public function handle(string $configFile, \Closure $next) {
-        $configurationData = array_merge(
+        $configurationData = array_replace_recursive(
             Yaml::parseFile(filename: __DIR__ . '/../../resources/build.defaults.yaml'),
             Yaml::parseFile(filename: $configFile),
         );