What should Meta teams do about it?

Test Jest with `require(esm)` in your monorepo — this unblocks hybrid workflows you've likely worked around • Review React Native image prefetch consolidation if you're using `enableImagePrefetchingAndroid` — behavior is now defaulted-on • Update to latest Jest for the `toStrictEqual` cross-realm fix if your tests use `structuredClone` with built-in types

Which Meta repositories shipped on May 2, 2026?

facebook/jest, facebook/react-native

JEST FINALLY SHIPS REQUIRE(ESM) — REACT NATIVE TIGHTENS ANDROID PLUMBING

By RepoJournal · Filed 06:02 UTC on May 2, 2026 · About Meta

Jest landed the feature engineers have asked for since ESM landed: you can now require() ES modules directly, no more dual-build nightmares.

The Jest team shipped `require(esm)` support [1] after re-implementing ESM on top of Node's `linkRequests` APIs [2], unblocking the hybrid CommonJS/ESM workflows that have plagued monorepos for years. They also fixed a critical cross-realm constructor bug in `toStrictEqual` [3] that broke equality checks on every built-in type when using `structuredClone`, and bumped Babel to 8.0.0-rc.4 [4] to keep the test runner aligned with the next-gen transpiler. On the React Native front, the Android team consolidated image prefetch flags [5] into a single control, removing deprecated `enableImagePrefetchingJNIBatchingAndroid` and `enableImagePrefetchingOnUiThreadAndroid` — batching and UI thread dispatch now default to on. They also fixed ThreadSanitizer data races in the inspector layer [6] that caught the JS and main threads reading unsynchronized state, and are testing a memory-efficient view registry swap [7] using `MutableIntObjectMap` instead of `ConcurrentHashMap` to eliminate boxing overhead on Android. Event dispatch correctness landed too [8], ensuring the new EventTarget-based dispatcher honors the legacy `skipBubbling` flag.

FAQ

What changed in Meta on May 2, 2026?: Jest landed the feature engineers have asked for since ESM landed: you can now require() ES modules directly, no more dual-build nightmares.
What should Meta teams do about it?: Test Jest with `require(esm)` in your monorepo — this unblocks hybrid workflows you've likely worked around • Review React Native image prefetch consolidation if you're using `enableImagePrefetchingAndroid` — behavior is now defaulted-on • Update to latest Jest for the `toStrictEqual` cross-realm fix if your tests use `structuredClone` with built-in types
Which Meta repositories shipped on May 2, 2026?: facebook/jest, facebook/react-native

JEST FINALLY SHIPS REQUIRE(ESM) — REACT NATIVE TIGHTENS ANDROID PLUMBING

The showcase is a teaser. Your wire is the product.

The showcase is a teaser.
Your wire is the product.