add nix flake

Author: BennoLossin

flake.lock

@@ -0,0 +1,36 @@
+{
+  inputs = {
+    fenix = {
+      url = "github:nix-community/fenix";
+      inputs.nixpkgs.follows = "nixpkgs";
+    };
+    flake-utils.url = "github:numtide/flake-utils";
+    nixpkgs.url = "nixpkgs/nixos-unstable";
+  };
+
+  outputs = {
+    self,
+    fenix,
+    flake-utils,
+    nixpkgs,
+  }:
+    flake-utils.lib.eachDefaultSystem (system: {
+      packages.default = let
+        toolchain = fenix.packages.${system}.minimal.toolchain;
+        pkgs = nixpkgs.legacyPackages.${system};
+      in
+        (pkgs.makeRustPlatform {
+          cargo = toolchain;
+          rustc = toolchain;
+        })
+        .buildRustPackage {
+          pname = "pinned-init";
+          version = "0.0.7";
+
+          src = ./.;
+
+          cargoLock.lockFile = ./Cargo.lock;
+        };
+    });
+}
+