Some suggested changes.

Dockerfile

@@ -1,4 +1,4 @@
-FROM python:alpine
+FROM python:3-alpine
 
 WORKDIR /usr/src/app
 
@@ -6,9 +6,11 @@ RUN apk add gcc musl-dev libffi-dev openssl-dev libxml2-dev libxslt-dev file llv
 
 COPY requirements.txt ./
 
-RUN pip install wheel cryptography gunicorn pymysql
+RUN pip install --no-cache-dir wheel cryptography gunicorn pymysql
 RUN pip install --no-cache-dir -r requirements.txt
 
+RUN apk del gcc musl-dev libffi-dev openssl-dev libxml2-dev libxslt-dev file llvm-dev make g++
+
 COPY . .
 
 RUN flask db init \

docker-compose.yml

@@ -1,13 +1,13 @@
-version: '3.4'
+version: '3.8'
 services:
   mariadb:
-    image: mariadb:latest
+    image: mariadb:10.5
     environment:
       MYSQL_ROOT_PASSWORD: changeme
       MYSQL_DATABASE: yotter
       MYSQL_USER: yotter
       MYSQL_PASSWORD: changeme
-    restart: on-failure
+    restart: unless-stopped
     volumes:
      - /var/lib/mysql
     healthcheck: