howto prebuild on gitpod with haskell and stack

Question

I have checked out https://github.com/gitpod-io/template-haskell and merged samples for a book (haskell in depth) into my branch.

Prebuilding has no effect, every opening of a workspace begins the entire build process from the beginning. So gitpod is effectively unusable for this project, as Zou have to wait for the entire build to complete, before ou can start using the workspace.

I presume the reason might be, that stack build stores the build artefacts in ~/.stack and that location is not part of the workspace, so it's lost when the workspace is closed.

Is that right? And then, how to keep the build result alive?

Answer 1

I just started using Gitpod so I'm not sure if there's a better way to do this, but I was able to get pretty close to what I wanted out of a prebuild by specifying a base dockerfile by putting this in my gitpod.yml:

image:
    file: .gitpod.Dockerfile

and then creating a .gitpod.Dockerfile that starts with

FROM gitpod/workspace-full

and then install ghcup and use it to install my other dependencies:

RUN curl --proto 'https' -tlsv1.2 -sSf https://downloads.haskell.org/~ghcup/x86_64-linux-ghcup > ./ghcup
RUN chmod 755 ./ghcup
RUN sudo mv ./ghcup /usr/local/bin

RUN ghcup install ghc
RUN ghcup install cabal
RUN ghcup install hls
RUN ghcup install stack
RUN sudo ln -s /home/gitpod/.ghcup/bin/stack /usr/local/bin/stack
RUN stack install ghcid