Add nix flake package

.gitignore

@@ -12,3 +12,4 @@
 /bin/index.mjs
 /.vscode
 /output-es/
+/result

CHANGELOG.d/feature_nix.md

@@ -0,0 +1,3 @@
+* Added nix flake
+* Updated README with nix example
+* Merged internal bin package with root to allow nix build

README.md

@@ -4,14 +4,18 @@ A port of the work done in [`purescript/purescript#4392`](https://github.com/pur
 
 ![ci badge](https://github.com/purescript-contrib/uplog/actions/workflows/ci.yml/badge.svg)
 
-## Install
+## Getting started
 
 The first working release is `v0.5.1`.
 
 ```sh
 npm i chnglg
 ```
 
+```sh
+nix run github:purescript-contrib/chnglg
+```
+
 ## Why
 
 To make it easier to keep a good changelog that

bin/index.dev.js

@@ -0,0 +1,2 @@
+#!/usr/bin/env node
+import("../output/Main/index.js").then(m => m.main())

flake.nix

@@ -0,0 +1,52 @@
+{
+  nixConfig.sandbox = "relaxed";
+
+  description = "A maintainer and contributor-friendly tool for generating a human-readable CHANGELOG.md";
+
+
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/nixpkgs-unstable";
+    utils.url = "github:ursi/flake-utils";
+    easy-ps.url = "github:justinwoo/easy-purescript-nix";
+    spago2nix.url = "github:justinwoo/spago2nix";
+  };
+
+  outputs = { self, utils, ... }@inputs:
+    utils.apply-systems
+      { inherit inputs; }
+      ({ system, pkgs, easy-ps, spago2nix, ... }:
+        let
+          chnglg = pkgs.stdenv.mkDerivation
+            {
+              name = "chnglg";
+              src = pkgs.nix-gitignore.gitignoreSource [ ".git" ] ./.;
+              nativeBuildInputs = [
+                easy-ps.purs
+              ] ++ (
+                spago2nix.spago2nix_nativeBuildInputs {
+                  srcs-dhall = [
+                    ./spago.dhall
+                    ./packages.dhall
+                  ];
+                }
+              );
+              unpackPhase = ''
+                cp -r $src/{src,bin} .
+                install-spago-style
+              '';
+              buildInputs = with pkgs; [ nodejs ];
+              buildPhase = ''
+                mkdir -p $out/bin
+                build-spago-style "./src/**/*.purs" "./bin/**/*.purs"
+                mv output $out/
+                install $src/bin/index.dev.js $out/bin/$name
+              '';
+            };
+        in
+        {
+          packages = {
+            inherit chnglg;
+            default = self.packages.${system}.chnglg;
+          };
+        });
+}

spago.dhall

@@ -2,7 +2,10 @@
 , dependencies =
   [ "aff"
   , "argonaut-codecs"
+  , "argparse-basic"
   , "arrays"
+  , "bifunctors"
+  , "console"
   , "control"
   , "datetime"
   , "effect"
@@ -20,6 +23,7 @@
   , "node-execa"
   , "node-fs"
   , "node-path"
+  , "node-process"
   , "nullable"
   , "parsing"
   , "precise-datetime"
@@ -30,5 +34,5 @@
   , "versions"
   ]
 , packages = ./packages.dhall
-, sources = [ "src/**/*.purs" ]
+, sources = [ "src/**/*.purs", "bin/**/*.purs" ]
 }