Use an alpine image rather than Debian buster: this is smaller

Dockerfile

@@ -1,26 +1,29 @@
-FROM python:3-buster
+FROM python:3-alpine
 
 ENV PYTHONUNBUFFERED 1
 
+# Install LaTeX requirements
+RUN apk add --no-cache gettext texlive nginx gcc libc-dev libffi-dev postgresql-dev
+
+RUN apk add --no-cache bash
+
 RUN mkdir /code
 WORKDIR /code
-
-# Install LaTeX requirements
-RUN apt update && \
-    apt install -y gettext texlive-latex-extra texlive-fonts-extra texlive-lang-french nginx && \
-    rm -rf /var/lib/apt/lists/*
+COPY requirements.txt /code/requirements.txt
+RUN pip install -r requirements.txt --no-cache-dir
 
 COPY . /code/
 
 # Configure nginx
-RUN ln -s nginx_tfjm.conf /etc/nginx/sites-available/tfjm.conf
-RUN rm /var/log/nginx/*.log
-RUN ln -s /dev/stdout /var/log/nginx/access.log
-RUN ln -s /dev/stderr /var/log/nginx/error.log
-RUN rm /etc/nginx/sites-enabled/default
-RUN ln -sf /code/nginx_tfjm.conf /etc/nginx/sites-enabled/tfjm.conf
+RUN mkdir /run/nginx
+RUN ln -sf /dev/stdout /var/log/nginx/access.log && ln -sf /dev/stderr /var/log/nginx/error.log
+RUN ln -sf /code/nginx_tfjm.conf /etc/nginx/conf.d/tfjm.conf
+RUN rm /etc/nginx/conf.d/default.conf
 
-RUN pip install -r requirements.txt
+# With a bashrc, the shell is better
+RUN ln -s /code/.bashrc /root/.bashrc
 
 ENTRYPOINT ["/code/entrypoint.sh"]
 EXPOSE 80
+
+CMD ["./manage.py", "shell_plus", "--ptpython"]