Add Nix and Flakes support

Split off from the refactor branch.

Signed-off-by: Dom Rodriguez <[email protected]>

bestool.nix

@@ -0,0 +1,25 @@
+{ lib
+, pkgs ? import <nixpkgs>
+, rustPlatform
+,
+}:
+rustPlatform.buildRustPackage {
+  name = "bestool";
+
+  src = lib.cleanSource ./.;
+
+  cargoLock = {
+    lockFile = ./Cargo.lock;
+    # Allow dependencies to be fetched from git and avoid having to set the outputHashes manually
+    allowBuiltinFetchGit = true;
+  };
+
+  nativeBuildInputs = with pkgs; [ pkg-config ];
+  buildInputs = with pkgs; [ systemd.dev ];
+
+  meta = with lib; {
+    description = "";
+    homepage = "https://github.com/Ralim/bestool";
+    license = licenses.mit;
+  };
+}

default.nix

@@ -0,0 +1,10 @@
+(import
+  (
+    let lock = builtins.fromJSON (builtins.readFile ./flake.lock); in
+    fetchTarball {
+      url = "https://github.com/edolstra/flake-compat/archive/${lock.nodes.flake-compat.locked.rev}.tar.gz";
+      sha256 = lock.nodes.flake-compat.locked.narHash;
+    }
+  )
+  { src = ./.; }
+).defaultNix

flake.nix

@@ -0,0 +1,41 @@
+{
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/nixpkgs-unstable";
+    flake-utils.url = "github:numtide/flake-utils";
+    flake-compat = {
+      url = "github:edolstra/flake-compat";
+      flake = false;
+    };
+  };
+  outputs =
+    { self
+    , nixpkgs
+    , flake-utils
+    , ...
+    }:
+    flake-utils.lib.eachDefaultSystem
+      (system:
+      let
+        pkgs = nixpkgs.outputs.legacyPackages.${system};
+      in
+      {
+        packages.bestool = pkgs.callPackage ./bestool.nix { };
+        packages.default = self.outputs.packages.${system}.bestool;
+
+        devShells.default = self.packages.${system}.default.overrideAttrs (super: {
+          nativeBuildInputs = with pkgs;
+            super.nativeBuildInputs
+            ++ [
+              cargo-edit
+              clippy
+              rustfmt
+            ];
+          RUST_SRC_PATH = "${pkgs.rustPlatform.rustLibSrc}";
+        });
+      })
+    // {
+      overlays.default = final: prev: {
+        inherit (self.packages.${final.system}) bestool;
+      };
+    };
+}