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πŸ“¨ #295: StyleX, browser(), Next.js, React Compiler, Vite, Bun, Astryx, Formisch, React-Aria, TanStack | C++ API, Margelo, Observe, Reanimated, Teleport, Nitro, Screen Transitions | Zod, pnpm, vgpu, Remix, Rspack, Webpack

Β· 14 min read
SΓ©bastien Lorber
SΓ©bastien Lorber
Newsletter creator - Docusaurus maintainer
Jan Jaworski
Jan Jaworski
React Native Developer

Hi everyone, Seb and Jan here πŸ‘‹!

Back from our summer break, we’ll cover news from the last two weeks.

React v19.3 is getting closer. The React Compiler in Rust is now available in Vite and Bun. CSS-in-JS is set to make a comeback.

On the mobile side, React Native keeps refining its public API surface, an important step toward v1.0. Callstack acquired Margelo.

Let's dive in!

As always, thanks for supporting us on your favorite platform:

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    βš›οΈ React​

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    StyleX, the atomic CSS-in-JS library from Meta, has been all the rage on X recently. This probably follows the 𝕏 Cursor migration from Tailwind to StyleX. Or maybe it’s related to Meta open-sourcing Astryx, the extensible, agent-friendly design system built on top and powering thousands of their apps for years.

    Anyway, we already covered all that, so here are the recent resources to check out:

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      πŸ“± React-Native​

      React Native RFC - Reducing the C/C++ public API

      React Native 1.0 is still on the horizon, but to respect Semantic Versioning, it first needs to clearly define its public API surface. Following the work on stable JS/TS and Java/Kotlin APIs, it’s now the turn of the C++ APIs to be clarified.

      Until now, there has been no clear distinction between public and private C++ APIs. As a result, community libraries and frameworks sometimes depend on APIs that were never intended to be public. This can cause libraries to break when upgrading React Native, or force the core team to preserve backward compatibility for internal APIs to avoid breaking the ecosystem.

      This RFC introduces a new three-tier visibility model for C++ APIs:

      • Public: Stable within major versions, safe for libraries to depend on, and exposed through a single umbrella header.
      • Framework: Stable within minor versions. Regular usage emits a suppressible warning.
      • Private: No stability guarantees. Regular usage emits a suppressible error.

      There’s existing tooling to take a snapshot of existing C++ APIs, that it will be adapted to take into accoun this new visibility model. All this will greatly help stabilize the C++ APIs and ensure React Native doesn’t ship unintended breaking changes.

      Work is already in progress to apply this visibility model to all C++ APIs. This will be rolled out gradually, first opt-in through a RN_STRICT_API build flag, then opt-out after a grace period, giving time for the public API consumers to migrate to the new umbrella headers. Most APIs have already been categorized, so if your library depends on private or framework APIs, now is probably a good time to chime in.

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      See ya! πŸ‘‹


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