Don't use nixpkgs-master anymore

programs/neovim/default.nix

@@ -1,17 +1,14 @@
 with import <nixpkgs> {};
 
-let
+{
-  nixpkgs-master = import <nixpkgs-master> {};
-in
-  {
   home-manager.users.charlotte = { pkgs, ... }: {
     nixpkgs.overlays = [
       (self: super: {
-          neovim = nixpkgs-master.neovim.override {
+        neovim = super.neovim.override {
           configure = (import ./base.nix { pkgs = self; }) ;
         };
       })
     ];
     home.packages = [ pkgs.neovim ];
   };
-  }
+}

programs/sway/waybar.nix

@@ -1,12 +1,9 @@
 { pkgs, ... }:
 
-let
-  nixpkgs-master = import <nixpkgs-master> {};
-in
 {
   home-manager.users.charlotte = { pkgs, ... }: {
       nixpkgs.overlays = [
-        (self: super: { waybar = nixpkgs-master.waybar.override { pulseSupport = true; mpdSupport = false; }; })
+        (self: super: { waybar = super.waybar.override { pulseSupport = true; mpdSupport = false; }; })
       ];
     xdg.configFile = {
       "waybar/config".text = ''

shells/accentor-api.nix

@@ -1,6 +1,5 @@
 let
   pkgs = import <nixpkgs> {};
-  nixpkgs-master = import <nixpkgs-master> {};
   baseVimConfig = import ../programs/neovim/base.nix { inherit pkgs; };
 in
   pkgs.mkShell {
@@ -10,7 +9,7 @@ in
       ruby_2_7
       taglib
       zlib
-      (nixpkgs-master.neovim.override {
+      (neovim.override {
         configure = {
           customRC = baseVimConfig.customRC + ''
             " Required for operations modifying multiple buffers like rename

shells/dodona.nix

@@ -1,6 +1,5 @@
 let
   pkgs = import <nixpkgs> {};
-  nixpkgs-master = import <nixpkgs-master> {};
   baseVimConfig = import ../programs/neovim/base.nix { inherit pkgs; };
   nodePackages = import ../packages/node/default.nix { inherit pkgs; };
 in
@@ -20,7 +19,7 @@ in
         child=$!
         wait $child
       '')
-      (nixpkgs-master.neovim.override {
+      (neovim.override {
         configure = {
           customRC = baseVimConfig.customRC + ''
             " Required for operations modifying multiple buffers like rename

shells/ledger.nix

@@ -1,10 +1,9 @@
 let
   pkgs = import <nixpkgs> {};
-  nixpkgs-master = import <nixpkgs-master> {};
   baseVimConfig = import ../programs/neovim/base.nix { inherit pkgs; };
 in
   pkgs.mkShell {
-    buildInputs = with nixpkgs-master; [
+    buildInputs = with pkgs; [
       (neovim.override {
         configure = {
           customRC = baseVimConfig.customRC;