chore: remove nixpkgs-unstable

configs/alacritty.nix

@@ -36,7 +36,7 @@ in {
   environment.variables.TERMINAL = "alacritty";
 
   environment.systemPackages = [
-    pkgs.unstable.alacritty
+    pkgs.alacritty
   ];
 
   home-manager.users.me.xdg.configFile = {

configs/git.nix

@@ -6,7 +6,7 @@
     pkgs.gitAndTools.hub
     pkgs.gitAndTools.gh
     pkgs.gitAndTools.git-extras
-    pkgs.unstable.gitAndTools.git-trim
+    pkgs.gitAndTools.git-trim
     pkgs.gitstats
     pkgs.patch
     pkgs.patchutils

configs/nixpkgs-unstable.nix

@@ -1,5 +0,0 @@
-{ config, ... }: {
-  nixpkgs.config.packageOverrides = pkgs: {
-    unstable = import <nixpkgs-unstable> { config = config.nixpkgs.config; };
-  };
-}

configs/packages/writing.nix

@@ -1,5 +1,9 @@
 { pkgs, lib, config, ... }:
 let
+  inherit (import <niveum/lib>) nixpkgs-unstable;
+
+  unstable = import nixpkgs-unstable {};
+
   zoteroStyle = { name, sha256 }: {
     name = "${name}.csl";
     path = pkgs.fetchurl {