[dnr]

I'm also using NixOS and working on Go projects, and had to deal with out-of-date Go releases. Nixpkgs generally does get the latest Go versions pretty quickly, but only in the unstable channels, they're not backported to NixOS releases. You can just grab that one package out of nixpkgs-unstable or nixos-unstable, like:

    (import (fetchTarball "https://github.com/NixOS/nixpkgs/archive/nixpkgs-unstable.tar.gz") {}).go_1_21

where you had `pkgs.go` before (in your shell.nix or wherever).