Update README.md

README.md

@@ -13,7 +13,7 @@
 
 ✅ Installs the `hayagriva` CLI globally \
 📌 Supports version pinning \
-⚡ Caches the installation in `$RUNNER_TOOL_CACHE` \
+⚡ Caches the compiled binary using [@actions/cache](https://www.npmjs.com/package/@actions/cache) \
 📥 Downloads from [the Hayagriva GitHub releases](https://github.com/typst/hayagriva/releases)
 
 ## Usage
@@ -55,4 +55,6 @@ jobs:
 
 This GitHub Action uses Bun to bundle the main entry point plus all the imported dependencies into a single `.js` file ready to be run by `main: dist/main.js` in the `action.yml`. To test the action just open a PR (even a draft one) and some magic GitHub Actions will test your changes. 🧙‍♂️
 
+⚠️ Hayagriva doesn't have a binary release on GitHub, nor does cargo-binstall have prebuilt binaries for it. Thus, we expect to compile it ourselves and cache it in the workflow cache. **This could change at any time if cargo-binstall adds prebuilds of hayagriva** which is why we still use cargo-binstall even though it just runs `cargo install hayagriva` right now.
+
 ℹ Once [Bun gets Windows support](https://github.com/oven-sh/bun/issues/43) make sure you add back the `runs-on: windows-latest` test to `test-action.yml`.