add flake config (using rustup lol)

.editorconfig

@@ -2,8 +2,11 @@ root = true
 
 [*]
 indent_style = space
-indent_size = 4
+indent_size = 2
 end_of_line = lf
 charset = utf-8
 trim_trailing_whitespace = false
 insert_final_newline = true
+
+[*.rs]
+indent_size = 4

flake.lock

@@ -0,0 +1,23 @@
+{
+  "nodes": {
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 0,
+        "narHash": "sha256-df3dJApLPhd11AlueuoN0Q4fHo/hagP75LlM5K1sz9g=",
+        "path": "/nix/store/ly4s3hw35dd1c2vsd694y2715pc1d2c1-source",
+        "type": "path"
+      },
+      "original": {
+        "id": "nixpkgs",
+        "type": "indirect"
+      }
+    },
+    "root": {
+      "inputs": {
+        "nixpkgs": "nixpkgs"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}

flake.nix

@@ -0,0 +1,14 @@
+{
+  description = "relay";
+
+  outputs = { self, nixpkgs }: let
+    pkgs = import nixpkgs { system = "x86_64-linux"; };
+  in {
+    devShells."x86_64-linux".default = pkgs.mkShell {
+      buildInputs = [
+        pkgs.rustup
+        pkgs.stdenv
+      ];
+    };
+  };
+}