diff --git a/Dockerfile b/Dockerfile
index 19a42f83e..bfaa937b9 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,6 +1,9 @@
 # pull official base image
 FROM python:3.12-slim-bookworm
 
+# Overridden in docker-compose.yml to fix tox in Docker
+ARG KEEP_DEPENDENCIES=False
+
 # set work directory
 WORKDIR /usr/src/app
 
@@ -34,11 +37,13 @@ RUN apt-get update \
         libpq-dev \
         zlib1g-dev \
     && python3 -m pip install --no-cache-dir -r ${REQ_FILE} \
-    && apt-get purge --assume-yes --auto-remove \
+    && if [ "${KEEP_DEPENDENCIES}" = "True" ]; then \
+        apt-get purge --assume-yes --auto-remove \
         gcc \
         libc6-dev \
         libpq-dev \
-        zlib1g-dev \
+        zlib1g-dev; \
+        fi \
     && rm -rf /var/lib/apt/lists/*
 
 # install node dependencies
diff --git a/docker-compose.yml b/docker-compose.yml
index 8f875e2b5..0730523cb 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -5,6 +5,7 @@ services:
             dockerfile: Dockerfile
             args:
                 - REQ_FILE=requirements/tests.txt
+                - KEEP_DEPENDENCIES=True
         entrypoint: ./docker-entrypoint.dev.sh
         command: python manage.py runserver 0.0.0.0:8000
         volumes: