I am currently on a quest to configure github actions in nix and wanted to use github-actions-dhall for that. I was at that point where it just doesnt want to find the package.dhall from the nix store when using it as a flake input so now I am trying to create and use a derivation of it. There are additional paths that need to be overwritten. Obviosly there is no internet access in the build phase on nix so with what and how can I overwrite lines like this one https://prelude.dhall-lang.org/v17.1.0/List/concatMap.dhall?
Propably with a link to the nix-store.
Maybe someone can point me in the right direction. 
Yes! There is Nixpkgs support for Dhall. See:
Hi!
I’m new to Dhall and trying to use it for some text processing.
I’m on NixOS and can not figure a couple of things out.
- The Nixpkgs documentation refers to
$ dhall freeze --inplace <dhall file>, but seems like it’s outdated. - The
dhallpackage onnixpkgsby default packaged with HTTP disabled, so$ dhall freezein a terminal or remote imports do not work and it’s impossible to add integrity check hashes. Is it expected? From the doc seems like it should be disabled only when building withnix.
I’ve resolved the issue. The issue didn’t even exist, I just had a slow-internet and misunderstood the strace output, omg 
. Just needed to wait for a while and got a hash.