fzakaria/nixpkgs-multiverse: Any version of any nixpkgs package, from one flake input

They also have a website with docs: https://nixmultiverse.com/docs/ [https://nixmultiverse.com/docs/] The website can also be used to search for specific package versions in nixpkgs, to get the nixpkgs revision: https://nixmultiverse.com/ [https://nixmultiverse.com/] The above feature is similar to: https://lazamar.co.uk/nix-versions/ [https://lazamar.co.uk/nix-versions/] or https://www.nixhub.io/ [https://www.nixhub.io/] , but using this project is a way easier alternative than searching for an pinning revisions.