Add nix flake

Author: DashieTM

.gitignore

@@ -210,4 +210,7 @@ dist
 .idea
 *.fs.js
 0.bundle.js
-.yarn
+.yarn
+
+# Nix
+.envrc

flake.lock

@@ -0,0 +1,97 @@
+{
+  description = "A fresh retake of the React API in Fable, optimized for happiness.";
+
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
+    flake-parts = {
+      url = "github:hercules-ci/flake-parts";
+      inputs.nixpkgs-lib.follows = "nixpkgs";
+    };
+    allSystems.url = "github:nix-systems/default";
+  };
+
+  outputs =
+    inputs@{ self, flake-parts, ... }:
+    flake-parts.lib.mkFlake { inherit inputs; } {
+      systems = import inputs.allSystems;
+
+      perSystem =
+        {
+          self',
+          lib,
+          pkgs,
+          system,
+          ...
+        }:
+        let
+          permittedPackages = [
+            "dotnet-core-combined"
+            "dotnet-wrapped-combined"
+            "dotnet-combined"
+            "dotnet-sdk-6.0.428"
+            "dotnet-sdk-wrapped-6.0.428"
+            "dotnet-sdk-6.0.136"
+          ];
+          libPath =
+            with pkgs;
+            lib.makeLibraryPath [
+              glib
+              nss
+              nspr
+              atk
+              cups
+              libdrm
+              dbus
+              expat
+              xorg.libX11
+              xorg.libXcomposite
+              xorg.libXdamage
+              xorg.libXext
+              xorg.libXfixes
+              xorg.libXrandr
+              xorg.libxcb
+              xorg.libxshmfence
+              libxkbcommon
+              libxcomp
+              libgbm
+              gtk3
+              pango
+              cairo
+              alsa-lib
+            ];
+        in
+        {
+          _module.args.pkgs = import self.inputs.nixpkgs {
+            inherit system;
+            config = {
+              permittedInsecurePackages = permittedPackages;
+            };
+          };
+          devShells.default = pkgs.mkShell {
+            inputsFrom = builtins.attrValues self'.packages;
+            env = {
+              # Will work as soon as PuppeteerSharp is updated on Fable Mocha
+              # Both are defined at https://pptr.dev/api/puppeteer.chromesettings
+              PUPPETEER_CHROME_SKIP_DOWNLOAD = true;
+              PUPPETEER_SKIP_CHROME_DOWNLOAD = true;
+              PUPPETEER_SKIP_DOWNLOAD = true;
+              NODE_OPTIONS = "--openssl-legacy-provider";
+              PUPPETEER_EXECUTABLE_PATH = "${pkgs.chromium}/bin/chromium";
+              PUPPETEER_BROWSER = "chrome";
+            };
+            packages = with pkgs; [
+              (
+                with dotnetCorePackages;
+                combinePackages [
+                  dotnetCorePackages.sdk_6_0
+                  dotnetCorePackages.sdk_8_0
+                ]
+              )
+              fantomas
+              chromium
+            ];
+            LD_LIBRARY_PATH = libPath;
+          };
+        };
+    };
+}