Configure cli flags via flake.nix

[garbas]

We already allow to configure (certain) nix.conf options via flake.nix (done in #4189). It would be very useful to extend this to also allow to configure cli flags via flake.nix.

[thufschmitt]

Shouldn't we rather make the relevant CLI flags nix.conf options ?

[zimbatm]

Are there specific examples?

[garbas]

An example would be part of the solution for #4609, where you could more in detail define your development environment variables with providing different defaults for --keep and --ignore-environment.

[stale]

I marked this as stale due to inactivity. → More info

[domenkozar]

I'd really like to setup a post build hook for flake commands.

[thufschmitt]

I'd really like to setup a post build hook for flake commands.

That’s slightly orthogonal: It’s already possible to set options in flake.nix (just not arbitrary cli flags, but post-build-hook is an option). The missing bit for your use-case is probably that these aren’t forwarded to the daemon atm. #5504 should fix that

[srid]

Shouldn't we rather make the relevant CLI flags nix.conf options ?

Are there specific examples?

Another example: In CI, I want to make --no-write-lock-file (in addition to --no-link) the default for all nix commands (nix build, nix flake check, nix develop), so as to handle the scenario where a developer forgot to commit the changes to the flake.lock file. See juspay/jenkins-nix-ci#15

If I can enable --no-write-lock-file in nix.conf of the build agent, all projects would automatically benefit from this check. And they do not have to individually check for lock file consistency (an error prone process because any of the Nix commands may overlook passing this option).