diff --git a/pkgs/by-name/st/strichliste/package.nix b/pkgs/by-name/st/strichliste/package.nix
index f81fceed7452..ca9221531e91 100644
--- a/pkgs/by-name/st/strichliste/package.nix
+++ b/pkgs/by-name/st/strichliste/package.nix
@@ -21,7 +21,7 @@ php.buildComposerProject2 (finalAttrs: {
   vendorHash = "sha256-PLq+XiZIJyyzVq+87timGO/jbPB4ZYQqSZilZMIE4Cw=";
   composerNoDev = true;
   composerNoPlugins = false;
-  composerStrictValidation = false;
+  composerStrictValidation = true;
 
   postPatch = ''
     substituteInPlace config/services.yaml \