Haskell Stack (using GHC 8.6.5) on jekyll/builder (on Alpine Linux)
See ednutting/jekyll-haskell-stack on Docker
See my other repositories for GHC-Up, GHC and Agda on Jekyll/builder.
You can FROM the associated docker image directly to use stack. It excludes the build sources.
Note: Give your Docker instance 4 CPUs and 8GB RAM minimum or the build may randomly fail.