Merge pull request #615 from vreuter/feature/add-nix-shell

Add small Nix shell for development

README.md

@@ -16,7 +16,15 @@ This project builds using [sbt][sbt].
 * build the documentation: `sbt ;documentation/mdoc; makeSite`
 * run benchmarks (you can provide [JMH][jmh] arguments in the end): `sbt benchmarksJVM/jmh:run`
 
+If you don't already have `sbt`, or if you'd like an isolated environment for development on this project, you may use the Nix shell. 
+For that, you must have the [Nix package manager][nix-download] installed on your machine, and you need to enable [Nix flakes][nix-flakes] and [Nix command][nix-command]. 
+With those prerequisites, from this project's root folder you just need to run `nix develop`.
+If you just want to enable the experimental Nix features (command and flakes) locally and temporarily, add the `--extra-experimental-features nix-command` and the `--extra-experimental-features flakes` option/argument pairs to the `nix develop` command.
+
 [fs2]: https://fs2.io/
 [sbt]: https://scala-sbt.org
 [jmh]: https://openjdk.java.net/projects/code-tools/jmh/
 [website]: https://fs2-data.gnieh.org
+[nix-download]: https://nixos.org/download/
+[nix-command]: https://nixos.wiki/wiki/Nix_command
+[nix-flakes]: https://nixos.wiki/wiki/Flakes

flake.nix

@@ -0,0 +1,26 @@
+{
+  inputs = {
+    typelevel-nix.url = "github:typelevel/typelevel-nix";
+    nixpkgs.follows = "typelevel-nix/nixpkgs";
+    flake-utils.follows = "typelevel-nix/flake-utils";
+  };
+
+  outputs = { self, nixpkgs, flake-utils, typelevel-nix }:
+    flake-utils.lib.eachDefaultSystem (system:
+      let
+        pkgs = import nixpkgs {
+          inherit system;
+          overlays = [ typelevel-nix.overlays.default ];
+        };
+      in
+      {
+        devShell = pkgs.devshell.mkShell {
+          imports = [ typelevel-nix.typelevelShell ];
+          name = "fs2-data-shell";
+          typelevelShell = {
+            jdk.package = pkgs.jdk11;
+          };
+        };
+      }
+    );
+}