diff --git a/Dockerfile.test b/Dockerfile.test
index debbfa8b..802eb3a4 100644
--- a/Dockerfile.test
+++ b/Dockerfile.test
@@ -21,4 +21,8 @@ RUN pip install --no-cache-dir \
 # Copy source
 COPY . .
 
+# pg_ctl refuses to run as root — create an unprivileged user
+RUN useradd -m testuser && chown -R testuser /app
+USER testuser
+
 CMD ["pytest"]