This Week In React #90: JSX, Tinybase, Dioxus, Owl, useWorkerizedReducer, Perf, TypeScript, CSS...

This Week In React #90: JSX, Tinybase, Dioxus, Owl, useWorkerizedReducer, Perf, TypeScript, CSS...

Hi everyone!

A week with various content, from interesting React articles to new tools leading to some healthy FOMO 😇

Parcel CSS reusing a Rust css parser initially created for Firefox, that's really cool!

I was also happy to notice that Node.js plainly supports Error Cause!

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Good advice on JSX conditionals

We like React because it's just JavaScript and we don't need to learn another templating language. But let's admin it's not always easy and there are some pitfalls to avoid 😅 This article gives a great overview.


Surma (Google) introduces a lib to use a Service Worker to create a React reducer (possibly async). Communication is efficiant thanks to ImmerJS and transmitting patches using postMessage. Browser support is good, only Firefox needs a polyfill. Now let's find a good use-case for this 🤷‍♂️, anyone?

An Inconsistent Truth: Next.js and Type Safety

Interesting thoughts on the current limits of end-2-end typing in Next.js, focusing on getServerSideProps and page props. There's either too much manual boilerplate (risk of error), or a type helper InferGetServerSidePropsType that might give surprisingly unsafe results. Evokes a TypeScript feature much-awaited by all frameworks: the ability to type module exports. Presents other solutions like Blitz, Server Components or tRPC. The last one looks quite interesting (see also the zart boilerplate using it).


New reactive store for structured data (in tables, like SQL or Normalizr), with a React integration package including hooks like useCell for efficient, fine-grained subscriptions. Small in size, but quite featured: index, relationships, undo/redo...


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React-Native-Owl: Visual Regression Testing for React-Native

This new solution runs your React-Native screens natively, takes screenshots, and compare them to the previously stored screenshots in ./owl to generate a report. All this is well-integrated with Jest (like snapshots).

Very happy to see visual regression testing progress for React-Native: this is very useful and React-Native has been left behind a bit compared to web. See also Storybook React-Native-Web permitting to do similar things with Chromatic, but requiring a web conversion.



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  • Software Mansion: the co-creators of React Native and the technological core of many tech companies


Parcel CSS

A new parser, compiler, minifier un CSS written in Rust, reusing rust-cssparser from Firefox. Outperforms competitors on terms of speed and output size (even esbuild). Integrated in Parcel, but can also be used standalone, in Rust or JavaScript (Webpack?), and even Deno or web (WASM)


New Rust framework largely inspired by React (hooks, VDOM, RSX...), strongly typed, performant, cross-platform (web, mobile, desktop, SSR). Aiming to be easy to adopt for a React/TypeScript dev.

I looked a bit the cross-platform support and I'm not sure yet how it works. It says native performance but seems to be using Tauri on desktop and mobile, afaik using WebViews? 🤔



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