nix-playgraound/notes/017-templates.md

Templates

This note covers 14-template/, which exposes templates.default so nix flake init -t can scaffold a new flake from files in the repository.

---

1. What a Template Output Is

A template output is metadata plus a path:

templates.default = {
  path = ./template;
  description = "Scaffold a tiny flake with one dev shell.";
};

The path points at the directory that should be copied into the new project. The description is what users see in nix flake show.

---

2. Why the Template Lives in Its Own Directory

The template is just ordinary files. In this example, template/ contains:

• a small flake.nix, and
• a short README.md.

That separation matters because the example flake and the template flake are doing different jobs:

• 14-template/flake.nix publishes the template, and
• 14-template/template/flake.nix is the scaffold that gets copied into a new directory.

---

3. Commands to Try

cd 14-template

nix flake show

mkdir /tmp/template-demo
cd /tmp/template-demo
nix flake init -t /path/to/nix-playground/14-template#default