diff --git a/docker/php/Dockerfile b/docker/php/Dockerfile
index a391943..1aba582 100644
--- a/docker/php/Dockerfile
+++ b/docker/php/Dockerfile
@@ -92,6 +92,7 @@ FROM base AS prod
 ARG APP_ENV=prod
 ENV APP_ENV=${APP_ENV}
 ENV APP_DEBUG=0 \
+    APP_SECRET=build-secret \
     DATABASE_DRIVER=sqlite \
     DATABASE_SQLITE_PATH=/var/www/html/var/data/database.sqlite \
     RUN_MIGRATIONS_ON_START=1