move flake to own repository

templates/rust_flake.nix

@@ -0,0 +1,36 @@
+# flake.nix
+{
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
+    rust-overlay.url = "github:oxalica/rust-overlay";
+  };
+
+  outputs = {self, nixpkgs, rust-overlay, ...}: let
+    system = "x86_64-linux";
+    pkgs = import nixpkgs {
+      inherit system;
+      overlays = [rust-overlay.overlays.default];
+    };
+    toolchain = pkgs.rust-bin.fromRustupToolchainFile ./toolchain.toml;
+  in {
+    devShells.${system}.default = pkgs.mkShell {
+
+      packages = with pkgs; [
+        cargo
+        clippy
+        rustc
+        rustfmt
+        toolchain
+        rust-analyzer-unwrapped
+        rust-analyzer
+      ];
+      env = {
+        RUST_BACKTRACE = "full";
+      };
+        RUST_SRC_PATH = "${toolchain}/lib/rustlib/src/rust/library";
+
+      # ...
+
+    };
+  };
+}