cache pip downloads

src/forest/Dockerfile

@@ -1,12 +1,13 @@
+# syntax = docker/dockerfile:1.6
 FROM python:3-bookworm
 
 # install dependencies
 RUN apt-get update && apt-get install -y --no-install-recommends \
-netcat-openbsd \
-gcc \
-&& \
-apt-get clean && \
-rm -rf /var/lib/apt/lists/*
+    netcat-openbsd \
+    gcc \
+    && \
+    apt-get clean && \
+    rm -rf /var/lib/apt/lists/*
 
 # create the appropriate directories
 ENV APP_HOME=/app
@@ -16,7 +17,8 @@ WORKDIR $APP_HOME
 # copy project
 COPY . $APP_HOME
 
-RUN pip3 install -r requirements.txt
+RUN --mount=type=cache,target=/root/.cache \
+    pip3 install -r requirements.txt
 
 EXPOSE 8080