Use uwsgi for docker container

Dockerfile

@@ -1,13 +1,25 @@
-FROM python:3.7.3-alpine3.9
+FROM python:3.7-slim
+
+RUN apt-get update && \
+    apt-get install -y gcc && \
+    pip3 install uwsgi && \
+    apt-get remove --purge -y gcc && \
+    apt-get autoremove -y
+
+EXPOSE 8000/tcp
+ENV HUMULUS_SETTINGS=/app/instance/settings.py
+ENV UWSGI_PROCESSES=4
+ENV UID=9000
+ENV GID=9000
 
 ADD . /app/
-
 WORKDIR /app
+RUN pip3 install --no-cache-dir .
 
-RUN pip install .
-RUN pip install waitress
-
-RUN mkdir -p /app/instance
-ENV HUMULUS_SETTINGS=/app/instance/settings.py
-
-CMD ["waitress-serve", "--call", "humulus:create_app"]
+CMD uwsgi --master \
+          --uid $UID \
+          --gid $GID \
+          --plugins python3 \
+          --http-socket :8000 \
+          -p ${UWSGI_PROCESSES} \
+          --module 'humulus:create_app()'