Running a dockerised development environment and wanting to make use of Jekyll, I was inspired by BretFisher/jekyll-serve to make something that fit in and could be re used for multiple sites.
Download the image
docker pull ghcr.io/willpower232/jekyll-toolkit
Create your new Jekyll site
docker run -it --rm -v $(pwd):/site jekyll-toolkit jekyll new .
Then reference it with docker-compose.yml (example in this repository).
docker build -t jekyll-toolkit .