Find it at: https://git.clan.lol/clan/select
Do you find accessing values from lists cumbersome? Is builtins.elemAt bringing you down? What about filtering nested dictionaries for specific keys?
For this reason, we hacked together an unmatched selection experience. It is written in pure Nix, without dependencies, to make your life 100% more “selectful.”
To use nix-select with the clan CLI, just run clan select.
Prominent features include:
- Globs:
* {a,b}(set-based selection).0(index-based access)
Example using the Clan CLI:
clan select 'nixosConfigurations.*.config.clan.core.vars.generators.*.files.*.{path,secret}'
This will print all variables defined in your Clan.
Here’s the equivalent non-selectful expression:
builtins.mapAttrs (
_: v0:
builtins.mapAttrs (
_: v1:
(builtins.mapAttrs (
_: v3:
builtins.intersectAttrs {
path = { };
secret = { };
} v3
) v1.files)
) v0.config.clan.core.vars.generators
) nixosConfigurations
clan select also uses a transparent caching technique, so running the same command again will be significantly faster.
There are many more operators and constructs supported in nix-select, all of which are documented in the README.
Usage Without Clan
You can also import our 100% pure Nix library and use it directly in your project today!
To use it inside any nix repl:
nix-repl> select = (builtins.getFlake "github:clan-lol/select").lib.select
With this, the select function can be used by simply passing it a query string and an attribute set or list:
nix-repl> select "*.config.networking.hostName" nixosConfigurations
The query language is intentionally designed to be compatible with the Nix grammar, so it might be possible to extend the Nix expression language to improve ease of use.
This project was developed during Thaigersprint 2025.
