diff --git a/flake.lock b/flake.lock
index f371881..aa3d695 100644
--- a/flake.lock
+++ b/flake.lock
@@ -6,11 +6,11 @@
         "rust-analyzer-src": "rust-analyzer-src"
       },
       "locked": {
-        "lastModified": 1770708269,
-        "narHash": "sha256-OnZW86app7hHJJoB5lC9GNXY5QBBIESJB+sIdwEyld0=",
+        "lastModified": 1770794449,
+        "narHash": "sha256-1nFkhcZx9+Sdw5OXwJqp5TxvGncqRqLeK781v0XV3WI=",
         "owner": "nix-community",
         "repo": "fenix",
-        "rev": "6b5325a017a9a9fe7e6252ccac3680cc7181cd63",
+        "rev": "b19d93fdf9761e6101f8cb5765d638bacebd9a1b",
         "type": "github"
       },
       "original": {
@@ -126,22 +126,39 @@
         "type": "github"
       }
     },
+    "nixpkgs_4": {
+      "locked": {
+        "lastModified": 1744536153,
+        "narHash": "sha256-awS2zRgF4uTwrOKwwiJcByDzDOdo3Q1rPZbiHQg/N38=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "18dd725c29603f582cf1900e0d25f9f1063dbf11",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixpkgs-unstable",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
     "root": {
       "inputs": {
         "fenix": "fenix",
         "flake-utils": "flake-utils",
         "naersk": "naersk",
-        "nixpkgs": "nixpkgs_3"
+        "nixpkgs": "nixpkgs_3",
+        "rust-overlay": "rust-overlay"
       }
     },
     "rust-analyzer-src": {
       "flake": false,
       "locked": {
-        "lastModified": 1770668050,
-        "narHash": "sha256-Q05yaIZtQrBKHpyWaPmyJmDRj0lojnVf8nUFE0vydcY=",
+        "lastModified": 1770702974,
+        "narHash": "sha256-CbvWu72rpGHK5QynoXwuOnVzxX7njF2LYgk8wRSiAQ0=",
         "owner": "rust-lang",
         "repo": "rust-analyzer",
-        "rev": "9efc1f709f3c8134c3acac5d3592a8e4c184a0c6",
+        "rev": "07a594815f7c1d6e7e39f21ddeeedb75b21795f4",
         "type": "github"
       },
       "original": {
@@ -168,6 +185,24 @@
         "type": "github"
       }
     },
+    "rust-overlay": {
+      "inputs": {
+        "nixpkgs": "nixpkgs_4"
+      },
+      "locked": {
+        "lastModified": 1770779462,
+        "narHash": "sha256-ykcXTKtV+dOaKlOidAj6dpewBHjni9/oy/6VKcqfzfY=",
+        "owner": "oxalica",
+        "repo": "rust-overlay",
+        "rev": "8a53b3ade61914cdb10387db991b90a3a6f3c441",
+        "type": "github"
+      },
+      "original": {
+        "owner": "oxalica",
+        "repo": "rust-overlay",
+        "type": "github"
+      }
+    },
     "systems": {
       "locked": {
         "lastModified": 1681028828,
diff --git a/flake.nix b/flake.nix
index 8c8c328..396ab59 100644
--- a/flake.nix
+++ b/flake.nix
@@ -6,6 +6,7 @@
     naersk.url = "github:nix-community/naersk";
     flake-utils.url = "github:numtide/flake-utils";
     fenix.url = "github:nix-community/fenix";
+    rust-overlay.url = "github:oxalica/rust-overlay";
   };
 
   outputs =
@@ -14,26 +15,34 @@
     flake-utils.lib.eachDefaultSystem (
       system:
       let
+        overlays = [ (import rust-overlay) ];
         pkgs = import nixpkgs {
-          inherit system;
-          overlays = [ fenix.overlays.default ];
+          inherit system overlays;
+          # overlays = [ rust-overlay.overlays.default ];
           # overlays = [cargo2nix.overlays.default];
         };
         naersk' = pkgs.callPackage naersk { };
 
+        # toolchain = (with pkgs.fenix.default; [cargo clippy rust-std rust-src rustc rustfmt rust-analyzer-nightly]);
+            
+
         nativeBuildInputs = with pkgs; [
           # Rust tools
-          alejandra
-          (pkgs.fenix.default.withComponents [
-            "cargo"
-            "clippy"
-            "rust-std"
-            "rustc"
-            "rustfmt"
-          ])
+          # toolchain
+          # (pkgs.fenix.default.withComponents [
+          #   "cargo"
+          #   "clippy"
+          #   "rust-std"
+          #   # "rust-src"
+          #   "rustc"
+          #   "rustfmt"
+          # ])
+          (rust-bin.selectLatestNightlyWith (toolchain: toolchain.default.override {
+            extensions = [ "rust-src" "rust-analyzer" "clippy" ];
+          }))
           cargo-nextest
           cargo-criterion
-          rust-analyzer-nightly
+          # rust-analyzer-nightly
           vulkan-loader
           wayland
           wayland-protocols
@@ -113,6 +122,7 @@
               inherit nativeBuildInputs buildInputs LD_LIBRARY_PATH;
               # LIBCLANG_PATH = "${pkgs.clang}";
               DATABASE_URL = "sqlite://./test.db";
+              # RUST_SRC_PATH = "${toolchain.rust-src}/lib/rustlib/src/rust/library";
             };
         defaultPackage = naersk'.buildPackage {
           inherit nativeBuildInputs buildInputs LD_LIBRARY_PATH;