Running Spress in Docker

My last PHP update broke Spress, the static site generator I use for this blog. I decided to move my blog generation to a more stable and portable environment - a Docker container. I’ve documented what I did and what I learned with this blog post. This is my first attempt to do something with Docker, please excuse any bad practices. You can find the finished Dockerfile at https://github.com/gbirke/spress-docker.