nixpkgs/neovim: use neovim nightly

.config/nixpkgs/neovim/flake.lock

@@ -1,5 +1,43 @@
 {
   "nodes": {
+    "flake-utils": {
+      "locked": {
+        "lastModified": 1644229661,
+        "narHash": "sha256-1YdnJAsNy69bpcjuoKdOYQX0YxZBiCYZo4Twxerqv7k=",
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "rev": "3cecb5b042f7f209c56ffd8371b2711a290ec797",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "type": "github"
+      }
+    },
+    "neovim-flake": {
+      "inputs": {
+        "flake-utils": "flake-utils",
+        "nixpkgs": [
+          "nixpkgs"
+        ]
+      },
+      "locked": {
+        "dir": "contrib",
+        "lastModified": 1647818703,
+        "narHash": "sha256-OY2R0lA0pp+GRTR7A9Y28LerMGSFJWvku/wgxpRXDl8=",
+        "owner": "neovim",
+        "repo": "neovim",
+        "rev": "e9b53f3fb56e91a0d4f15bb36d8068bcc6ea88cf",
+        "type": "github"
+      },
+      "original": {
+        "dir": "contrib",
+        "owner": "neovim",
+        "repo": "neovim",
+        "type": "github"
+      }
+    },
     "nixpkgs": {
       "locked": {
         "lastModified": 1647350163,
@@ -16,6 +54,7 @@
     },
     "root": {
       "inputs": {
+        "neovim-flake": "neovim-flake",
         "nixpkgs": "nixpkgs"
       }
     }

.config/nixpkgs/neovim/flake.nix

@@ -1,10 +1,22 @@
 {
   description = "Neovim configuration";
 
-  outputs = { self, nixpkgs }: {
+  inputs = {
+    neovim-flake.url = "github:neovim/neovim?dir=contrib";
+    neovim-flake.inputs.nixpkgs.follows = "nixpkgs";
+  };
+
+  outputs = { self, nixpkgs, neovim-flake }: {
+
+    overlay = final: prev: {
+      neovim-unwrapped = neovim-flake.packages.${prev.system}.neovim;
+    };
 
     packages.x86_64-linux.default =
-      with nixpkgs.legacyPackages.x86_64-linux;
+      with import nixpkgs {
+        system = "x86_64-linux";
+        overlays = [ self.overlay ];
+      };
       let
         extraPath = [
           fzf