Uploaded September 2025 | Updated September 2026, 2 days ago
For over a decade, React has lived in a single-threaded universe: one JavaScript thread handling events, logic, and rendering. But what if React had been designed differently. What if it embraced two threads from the very beginning?
At React Universe Conf 2025, Xuan Huang, Ziqi Zhen, and Haoyang Wang from ByteDance introduce React for two threads, a paradigm shift in how React applications can be built and executed.
Skip the intro ⏩ 0:39
🔹 The tradeoffs of React’s single-threaded model, and why it limits performance.
🔹 A dual-thread approach that enables instant first-frame rendering, reduced interaction latency, and smoother animations.
🔹 New abstractions like Main Thread Functions (MTFs) and Main Thread Components (MTCs) that bring synchronous UI updates and full reactivity back to the main thread.
🔹 Real-world demos: from sliders to color pickers, showing how responsiveness improves when event handling is split intelligently across threads.
🔹 Lynx: ByteDance’s production-ready framework implementing the two-thread model, already powering TikTok features, and now extended to the web using Web Workers.
See you at another React Universe Conf 🎟️ clstk.com/3JSmUZK
Follow React Universe Conf on X to stay up to date 🐦 https://x.com/reactuniverse_
Check out Callstack content 📚 clstk.com/4ggp01K
For over a decade, React has lived in a single-threaded universe: one JavaScript thread handling events, logic, and rendering. But what if React had been designed differently. What if it embraced two threads from the very beginning?
At React Universe Conf 2025, Xuan Huang, Ziqi Zhen, and Haoyang Wang from ByteDance introduce React for two threads, a paradigm shift in how React applications can be built and executed.
Skip the intro ⏩ 0:39
🔹 The tradeoffs of React’s single-threaded model, and why it limits performance.
🔹 A dual-thread approach that enables instant first-frame rendering, reduced interaction latency, and smoother animations.
🔹 New abstractions like Main Thread Functions (MTFs) and Main Thread Components (MTCs) that bring synchronous UI updates and full reactivity back to the main thread.
🔹 Real-world demos: from sliders to color pickers, showing how responsiveness improves when event handling is split intelligently across threads.
🔹 Lynx: ByteDance’s production-ready framework implementing the two-thread model, already powering TikTok features, and now extended to the web using Web Workers.
See you at another React Universe Conf 🎟️ clstk.com/3JSmUZK
Follow React Universe Conf on X to stay up to date 🐦 https://x.com/reactuniverse_
Check out Callstack content 📚 clstk.com/4ggp01K
