diff --git a/flask-redis/Dockerfile b/flask-redis/Dockerfile
index 046e76c..6eab7cc 100644
--- a/flask-redis/Dockerfile
+++ b/flask-redis/Dockerfile
@@ -14,14 +14,11 @@ CMD ["app.py"]
 
 FROM builder as dev-envs
 
-RUN <<EOF
-apk update
-apk add git bash
-EOF
+RUN apt update && \
+apt add git bash
 
-RUN <<EOF
-addgroup -S docker
+
+RUN addgroup -S docker && \
 adduser -S --shell /bin/bash --ingroup docker vscode
-EOF
 # install Docker tools (cli, buildx, compose)
 COPY --from=gloursdocker/docker / /