Fortunately, `builtins.fetchTarball` makes this easier. I do this in my `nixcfg` repo so that I can build my entire machine config (patches and enabling Iris in Mesa, and all) on a stupidly-cheap Packet.net VM:
https://github.com/colemickens/nixcfg/blob/master/default.ni....
If you follow the rabbit-hole: `default.nix` -> `lib.nix`, etc, you can see that I pin nixpkgs, have an update script that updates the nixpkgs revs I build against, it supports building against a custom, local `~/code/nixpkgs` if it exists, and I have my machine config abstracted out to where I can build a "GNOME instance of my machine" or by default, my machine with Sway and sway related packages installed. Much of this should be easier with flakes, as I understand it.
It's not the cleanest config, the README needs love, but maybe it can be inspiration in the meantime. :) My latest trick was figuring out how to get the new Mesa Intel Iris Gallium driver enabled without rebuilding the world, and I extracted it to what I call a "mixin" that anyone can copy and just use: https://github.com/colemickens/nixcfg/blob/master/modules/mi...
(And technically I still use mozilla/nixpkgs-mozilla to pull the latest Firefox Nightly which is impure and thus not always perfectly, perfectly reproducable. I do however pin the overlays themselves also - like my nixpkgs-wayland overlay that packages HEAD versions of Sway and other Wayland related tools!)
If you follow the rabbit-hole: `default.nix` -> `lib.nix`, etc, you can see that I pin nixpkgs, have an update script that updates the nixpkgs revs I build against, it supports building against a custom, local `~/code/nixpkgs` if it exists, and I have my machine config abstracted out to where I can build a "GNOME instance of my machine" or by default, my machine with Sway and sway related packages installed. Much of this should be easier with flakes, as I understand it.
It's not the cleanest config, the README needs love, but maybe it can be inspiration in the meantime. :) My latest trick was figuring out how to get the new Mesa Intel Iris Gallium driver enabled without rebuilding the world, and I extracted it to what I call a "mixin" that anyone can copy and just use: https://github.com/colemickens/nixcfg/blob/master/modules/mi...
(And technically I still use mozilla/nixpkgs-mozilla to pull the latest Firefox Nightly which is impure and thus not always perfectly, perfectly reproducable. I do however pin the overlays themselves also - like my nixpkgs-wayland overlay that packages HEAD versions of Sway and other Wayland related tools!)