Docs, and rebuild dist

README.md

@@ -2,20 +2,30 @@
 
 **WORK IN PROGRESS**
 
-Generates a Nix expression to build a Yarn v2 package.
+Generates a Nix expression to build a Yarn v2 project (not using zero-install).
 
 ## Usage
 
 ```sh
 yarn plugin import https://raw.githubusercontent.com/stephank/yarn-plugin-nixify/main/dist/yarn-plugin-nixify.js
 yarn
-yarn nixify
 nix-build
 ```
 
-The `yarn nixify` command always updates `yarn-project.nix`, but only writes a
+Running `yarn` with this plugin enabled will generate two files:
-(minimal) `default.nix` if it doesn't exist yet. The `default.nix` is intended
+
-to be customized, for example:
+- `yarn-project.nix`: This file is always overwritten, and contains a basic
+  derivation for your project.
+
+- `default.nix`: Only generated if it does not exist yet. This file is intended
+  to be customized with any project-specific logic you need.
+
+When building the basic derivation without any customization, it'll run `yarn`
+inside your project, copy your project to `$out/libexec/<name>`, and setup
+wrappers in `$out/bin` for any executables declared in the `bin` field of your
+top-level `package.json`.
+
+Some examples of how to customize your build from within `default.nix`:
 
 ```nix
 { pkgs ? import <nixpkgs> { } }:
@@ -62,4 +72,5 @@ yarn build-dev
 yarn plugin import /path/to/yarn-plugin-nixify/dist/yarn-plugin-nixify.dev.js
 ```
 
-(Alternatively, add a direct reference in `.yarnrc.yml`.)
+(Alternatively, add a direct reference in `.yarnrc.yml`. This will likely only
+work if the Nix sandbox is disabled.)

src/generate.ts

@@ -34,6 +34,7 @@ export default async (project: Project, cache: Cache, report: Report) => {
   const yarnPathAbs = configuration.get(`yarnPath`);
   const cacheFolderAbs = configuration.get(`cacheFolder`);
 
+  // Sanity checks.
   let yarnPath = ppath.relative(cwd, yarnPathAbs);
   if (yarnPath.startsWith(`../`)) {
     yarnPath = yarnPathAbs;