Setup nix flake

Author: paholg

.envrc

@@ -0,0 +1 @@
+use flake

.gitignore

@@ -1,5 +1,2 @@
 target
-Cargo.lock
-
-*.bk
-*\~
+.direnv/

Cargo.lock

@@ -0,0 +1,42 @@
+{
+  inputs = {
+    nixpkgs.url = "nixpkgs/nixos-unstable";
+    flake-utils.url = "github:numtide/flake-utils";
+    rust-overlay.url = "github:oxalica/rust-overlay";
+  };
+
+  outputs =
+    {
+      nixpkgs,
+      flake-utils,
+      rust-overlay,
+      ...
+    }:
+    flake-utils.lib.eachDefaultSystem (
+      system:
+      let
+        overlays = [
+          (import rust-overlay)
+        ];
+        pkgs = import nixpkgs {
+          inherit system overlays;
+        };
+
+        rust = pkgs.rust-bin.stable.latest.default.override {
+          extensions = [
+            "rust-analyzer"
+            "rust-src"
+          ];
+        };
+      in
+      {
+        devShells.default = pkgs.mkShell {
+          packages = [
+            pkgs.just
+            rust
+          ];
+        };
+
+      }
+    );
+}