add nix flake

Author: kaesaecracker

README.md

@@ -19,6 +19,11 @@ The optimization relies on a simple 2-fold logic:
 pip install optimal-congress
 ```
 
+With nix, you can run this application directly (contact [kaesaecracker](https://github.com/kaesaecracker) if this does not work):
+```bash
+nix run github:top-on/optimal-congress
+```
+
 ## Available commands
 
 `optimal-congress` provides the following commands:

flake.lock

@@ -0,0 +1,52 @@
+{
+  description = "Flake for optimal-congress";
+
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/nixos-24.11";
+    poetry2nix = {
+      url = "github:nix-community/poetry2nix";
+      inputs.nixpkgs.follows = "nixpkgs";
+    };
+  };
+
+  outputs =
+    {
+      self,
+      nixpkgs,
+      poetry2nix,
+    }:
+    let
+      lib = nixpkgs.lib;
+      forAllSystems = lib.genAttrs [
+        "x86_64-linux"
+        "aarch64-linux"
+        "aarch64-darwin"
+        "x86_64-darwin"
+      ];
+      poetryConfig = {
+        projectDir = ./.;
+        # when compiling locally, this flake does not work because transitive rust dependencies are not version pinned
+        preferWheels = true;
+      };
+    in
+    {
+      apps = forAllSystems (
+        system:
+        let
+          pkgs = nixpkgs.legacyPackages."${system}";
+          inherit (poetry2nix.lib.mkPoetry2Nix { inherit pkgs; }) mkPoetryApplication;
+          myPythonApp = mkPoetryApplication poetryConfig;
+        in
+        rec {
+          optimal-congress = {
+            type = "app";
+            program = "${myPythonApp}/bin/optimal-congress";
+          };
+
+          default = optimal-congress;
+        }
+      );
+
+      formatter = forAllSystems (system: nixpkgs.legacyPackages."${system}".nixfmt-rfc-style);
+    };
+}