Add Nix support

Author: mawkler

.envrc

@@ -0,0 +1 @@
+use flake

.gitignore

@@ -1,4 +1,5 @@
 /target
 .env
+.direnv/
 sso_login/node_modules/
 maconomy_cookie

flake.lock

@@ -0,0 +1,37 @@
+{
+  inputs = {
+    naersk.url = "github:nix-community/naersk/master";
+    nixpkgs.url = "github:NixOS/nixpkgs/nixpkgs-unstable";
+    utils.url = "github:numtide/flake-utils";
+  };
+
+  outputs = { nixpkgs, utils, naersk, ... }:
+    utils.lib.eachDefaultSystem (system:
+      let
+        pkgs = import nixpkgs { inherit system; };
+        naersk-lib = pkgs.callPackage naersk { };
+      in {
+        defaultPackage = naersk-lib.buildPackage {
+          src = ./.;
+          # The binary is called `maconomy`, not `maconomy-cli`
+          pname = "maconomy";
+        };
+        devShell = with pkgs;
+          mkShell {
+            buildInputs = [
+              # Rust stuff
+              cargo
+              rustc
+              rustfmt
+              pre-commit
+              rustPackages.clippy
+
+              # Other
+              openssl
+              pkg-config
+              chromium
+            ];
+            RUST_SRC_PATH = rustPlatform.rustLibSrc;
+          };
+      });
+}