.envrc: don't enable flakes extra-experimental-feature

[flokli]

There's nothing in this repository using flakes, and setting this causes my system to just block entirely:

❯ cd dev/wire/wire-server
direnv: error /home/flokli/dev/wire/wire-server/.envrc is blocked. Run `direnv allow` to approve its content
❯ direnv allow
direnv: loading ~/dev/wire/wire-server/.envrc
🔧 Building environment
warning: unknown experimental feature 'flakes'
warning: unknown experimental feature 'flakes'
⏱ 4sdirenv: ([/nix/store/0lf6mkfaqx4zmsni9yys650qx573zfcw-direnv-2.33.0/bin/direnv export zsh]) is taking a while to execute. Use CTRL-C to give up.
⏱ 8s^C
^C^X^C^C^C

Checklist

• Add a new entry in an appropriate subdirectory of changelog.d
• Read and follow the PR guidelines

[smatting]

Yes, we are using flakes here github:wireapp/ghc-flakr. But since we don't use ghc-flakr and we haven't decided if we want to use it, let's maybe remove it?

[MangoIV]

This was requested by @elland to make using hs-run easier (it uses flakes).

[MangoIV]

I guess if you get stuck, it would be better to remove it from the envrc altogether and load it only on demand?

[flokli]

There's a single occurence in the hack/bin/bombon.hs shell script, which uses nix run:

1:#!/usr/bin/env -S nix -Lv run github:wireapp/ghc-flakr/ecb1f45f1549e06c92d71164e305ce501eb0e36e

@elland could you (and everyone invoking hack/bin/bombon.hs enable this on your system-wide config?

[MangoIV]

I think it's easier to not have it automatically load in wire-server and instead just use it explicitly in a devShell or in the shebang and then pass the argument along, if you don't have the feature enabled?

[flokli]

Good point, lemme just update this PR to change the shebang.

[MangoIV]

@flokli do you have some special setup that flakes feature makes you get stuck? I don't think it should have any effect as long as it's not used...

[flokli]

I assume Nix behaves a bit stupidly if it encounters an experimental feature it doesn't know about, or nom does, but yes, I do have some patches, and my Nix doesn't know about the flakes experimental feature.

However, I also think we should only be adding stuff we actually need. I moved the invocation to the shebang in hack/bin/bombon.hs (which I can't test by myself).

I'd argue this script could also be rewritten in bash, saving us a bunch of startup to evaluate nixpkgs, compile the binary and haskell interpreter. The only thing it does is invoking nix build -f nix wireServer.allLocalPackagesBom (which could also be rewritten to nix-build nix -A wireServer.allLocalPackagesBom), and trhen invoke the gh binary - but I lack context on this script and it's a bit too far out of scope for this PR, which does the minimal thing - unblocking my shell while hopefully not breaking someone others' workflow ;-)

[MangoIV]

yeah, the script is a proof of concept.

[flokli]

closing in favor of #3778.