Green Tea 26.9.0-beta.2: the runtime entry points boot before they bind

Green Tea 26.9.0-beta.2 went out to npm and JSR on 22 September 2026.

There are two breaking changes and each one is a keyword to fix. They are also the same mistake twice: both are places where Green Tea asked you to do something in the right order, which is the one thing the framework is supposed to work out for you.

A port that opened before the app had started

serveDeno and serveBun used to open their port without booting the app. The providers ran on the first request instead, and whatever happened then was remembered, including a failure.

So forgetting the documented workaround did not give you a failed start. The port opened. Any health check that asks “is something listening” passed. Then every request came back 500 — from the runtime, not from Green Tea, so it never reached your onError and never showed up in your logs. A missing signing key got you a process that looked fine and served nothing.

Both functions are async now and boot before they bind:

- const server = serveDeno(app, { port });
+ const server = await serveDeno(app, { port });

They still resolve to the same value, and both runtimes have top-level await, so a module that serves when it is imported needs nothing else. A provider that cannot start now breaks the deploy, where you can see it.

edgeHandler stays as it was. Cloudflare Workers gives you no startup outside a request, so there is no earlier moment to fail in.

Plugins are named objects

A plugin used to be a function, and plugin:mounted took its name from the function’s name property. That is empty for an arrow function returned by a factory, which is how most plugins are written. The event whose job is to say which plugins mounted named none of them.

A plugin is { name, mount(api) } now. You say what it is called instead of hoping the runtime guesses. A failed mount reports plugin "<name>" failed to mount: … and keeps the original error as its cause, and two plugins with the same name fail createApp rather than quietly shadowing each other.

This is the small half of a bigger change. There is a plugin marketplace on the way, and what an ecosystem needs from a plugin contract before strangers start publishing into it gets its own post.

Also in this release

app.boot() is public, for apps that drive app.fetch from their own server. Framework errors are now recognised by a symbol brand rather than instanceof, so an Unauthorized thrown by a package carrying its own copy of Green Tea renders with its real status instead of turning into a 500. Mesh is still alpha, and it no longer lets you export a provider: a provider’s value is an object, and an object is not what a JSON connection carries.

The changelog lists everything, and the documentation covers this release.

Upgrading

npm i @green-tea/core@beta

If you run on Node, neither breaking change touches you: app.listen() has always booted before accepting connections. On Deno or Bun you need the await. If you write plugins you need the object form, and if you use one you need whichever version of it adopts the object form.

Green Tea is still beta and versions by calendar. The API can change between betas, and anything that breaks is named in the changelog.