Add flake.nix

flake.nix

@@ -0,0 +1,33 @@
+{
+  description = "OffBroadwayRedisStream Development Environment";
+
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/nixos-24.05";
+    utils.url = "github:numtide/flake-utils";
+  };
+
+  outputs =
+    {
+      self,
+      nixpkgs,
+      utils,
+    }:
+    utils.lib.eachDefaultSystem (
+      system:
+      let
+        pkgs = import nixpkgs { inherit system; };
+      in
+      {
+        devShells.default = pkgs.mkShell {
+          buildInputs = with pkgs; [
+            # this is needed for postgres to pick UTF-8
+            glibcLocales
+            redis
+            nixfmt-rfc-style
+          ];
+        };
+
+        formatter = pkgs.nixfmt-rfc-style;
+      }
+    );
+}