Reproducible build environment with nix

.envrc

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

.github/workflows/build_nix.yml

@@ -0,0 +1,13 @@
+name: "Build legacy Nix package on Ubuntu"
+
+on:
+  push:
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - uses: cachix/install-nix-action@v26
+      - name: Building package
+        run: nix build 

.gitignore

@@ -1,5 +1,8 @@
 /target
 **/*.rs.bk
 
+# Nix build output
+/result
+
 # File used as the piped output of Sapling (I use it for debugging)
 log

README.md

@@ -112,6 +112,9 @@ git clone https://github.com/kneasle/sapling.git
 cargo run 2> log
 ```
 
+If you have Nix you can also run `nix build` and `./result/bin/sapling 2> log`, or if you don't mind
+seeing stderr output even quicker with `nix run`. 
+
 ### Demo
 
 ![Demo GIF](https://user-images.githubusercontent.com/60934058/112751246-d8e23f00-8fc4-11eb-9a15-8a3ef32d54a4.gif)

default.nix

@@ -0,0 +1,10 @@
+{ pkgs ? import <nixpkgs> { } }:
+let
+  manifest = (pkgs.lib.importTOML ./Cargo.toml).package;
+in 
+pkgs.rustPlatform.buildRustPackage rec {
+  pname = manifest.name;
+  version = manifest.version;
+  cargoLock.lockFile = ./Cargo.lock;
+  src = pkgs.lib.cleanSource ./.;
+}

flake.nix

@@ -0,0 +1,19 @@
+{
+  description = "Sapling text editor";
+  inputs = {
+    nixpkgs.url = "github:nixos/nixpkgs/nixos-unstable";
+  };
+  outputs = { self, nixpkgs }:
+    let
+      supportedSystems = [ "x86_64-linux" ];
+      forAllSystems = nixpkgs.lib.genAttrs supportedSystems;
+      pkgsFor = nixpkgs.legacyPackages;
+    in {
+      packages = forAllSystems (system: {
+        default = pkgsFor.${system}.callPackage ./default.nix { };
+      });
+      devShells = forAllSystems (system: {
+        default = pkgsFor.${system}.callPackage ./shell.nix { };
+      });
+    };
+}

shell.nix

@@ -0,0 +1,9 @@
+{ pkgs ? import <nixpkgs> { } }:
+pkgs.mkShell {
+  inputsFrom = [ (pkgs.callPackage ./default.nix { }) ];
+  buildInputs = with pkgs; [
+    rust-analyzer # LSP Server
+    rustfmt       # Formatter
+    clippy        # Linter
+  ];
+}