Ready for Concurrent Mode?
summary
Early Facebook experiments show Concurrent Mode yields the main thread during rendering, enabling unstable_createRoot scheduling and idle pre-rendering but exposing real bugs: visible tearing of header/footer, input lag from setTimeout callbacks, duplicate saves when side effects run during the render phase, double constructors creating duplicate subscriptions, and inconsistent trees from a mutable store. Fixes used are coordinating non-React work with the scheduler, moving side effects to the commit phase, adopting an immutable store, and testing with React Strict Mode and hooks/suspense.
AI-written summary · about
chapters (8)
- 0:00Start
- 3:36looking at a timeline of the initial page
- 7:35render the whole app in concurrent mode
- 11:55give set timeout a callback
- 16:41remove all the deprecated lifecycle methods from your app
- 17:40remove all the side effects from the render face
- 20:20summarize the fix
- 24:36experiment with javascript scheduling
