Except in Nixpkgs, where it's tedious to go from the package's expression (easy enough to find from NixOS Search) to where it's called in `all-packages.nix` or

Except in Nixpkgs, where it's tedious to go from the package's expression (easy enough to find from NixOS Search) to where it's called in `all-packages.nix` or to the various helpers exposed in `lib`. But there are multiple efforts to make jumping to declarations easier in the new CLI and even to rearchitect Nixpkgs.