jsx-runtime

A plugin-based JSX runtime for UI5, write UI5 views as .tsx files with per-control TypeScript typing, no React, no VDOM, no reconciler. JSX expressions compile to plain new Control(settings) calls; a stable five-extension-point plugin SPI lets frameworks and libraries layer features on top of the core without touching it.

import Button from "sap/m/Button";
import Page from "sap/m/Page";

export default class Main extends View {
    createContent() {
        return (
            <Page title="Hello">
                <Button text="Click me" press=".onPress" />
            </Page>
        );
    }
}

Repository layout

This is a pnpm-workspace monorepo with three packages:

Package	Path	Description
@ui5-community/jsx-runtime	packages/jsx-runtime/	The library. Ships the core JSX runtime and the <Switch> sample plugin. Publishable to npm.
@ui5-community/jsx-runtime-showcase	packages/jsx-runtime-showcase/	The showcase app. Runs the library end-to-end and doubles as living documentation on GitHub Pages. Not published.
@ui5-community/jsx-runtime-helloworld	packages/jsx-runtime-helloworld/	Minimal reference app — a plain scaffolded UI5 TypeScript project that consumes the runtime the way an external project would. Proves the from-scratch adoption path. Not published.

Additional docs live in docs/:

• docs/jsx-runtime.md, the concept overview (extended from the POC's webapp/jsx-runtime/README.md).
• docs/requirements.md, the full requirements spec for the runtime.
• docs/performance.md, how JSX instantiation compares to XMLView (with measured numbers).
• docs/xmlview-to-tsx.md, step-by-step guide for converting an app's .view.xml files to .tsx views.

Getting started

Requires Node.js ≥ 22.13 (the Node 22 LTS line) and pnpm ≥ 11. A .nvmrc pins the Node major — run nvm use if you use nvm.

# 1) install
pnpm install

# 2) run the showcase (also the dev harness for the library)
pnpm dev
# → http://localhost:8080

# 3) build all packages
pnpm build

# 4) run all tests (QUnit for the library, OPA5 for the showcase, via ui5-test-runner)
pnpm test

# optional: run the minimal reference app (see how an external project consumes the runtime)
pnpm dev:helloworld
# → http://localhost:8080

Editing a file in packages/jsx-runtime/src/ while pnpm dev runs triggers ui5-middleware-livereload in the browser, no rebuild step needed. pnpm's workspace symlink and ui5-tooling-transpile-middleware do the rest.

Concepts at a glance

The runtime provides three layers of API surface:

1. Core directives: jsx, <Fragment>, <For>, <If>. Always available, no setup.
2. Plugin SPI: five extension points (Renderer, IntrinsicHandler, PropertyApplier, ChildrenProcessor, Scope) let plugins add directives, intrinsics, and output adapters without touching the core.
3. Sample plugin: <Switch>/<Case>/<Default> in packages/jsx-runtime/src/plugins/switch/ proves the SPI on a non-trivial example.

Detailed rationale, walk-throughs, and API references are in docs/jsx-runtime.md.

License

Apache License 2.0.