I'm curious, how does React Native's so-called "bridge" architecture work? How does it transition from JavaScript to native code? How optimized is this process in terms of performance? I have a lot of questions swirling in my head, so I'd appreciate some clarification.
How does React Native achieve native performance?
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Man, you really asked a great question. When I first started with React Native, I was obsessed with this bridge thing. The whole “JavaScript to native code” transition is actually a pretty clever design. Nowadays there’s a newer, more innovative system called **JSI (JavaScript Interface)**, but the old **bridge** still works. In the old bridge, the flow was: a message goes from the JS thread to the native side, native picks it up and runs it, then sends the response back to JS. It’s not synchronous because JS is single‑threaded, so it hurt performance.
Now we have **JSI**, which lets JS and native talk directly, eliminating the serialize/deserialize hassle. As for the performance worries you mentioned, React Native also has to optimize rendering on the JS side because of that bridge system. For example, you need to minimize re‑renders in FlatLists by using things like `shouldItemUpdate`. I’ve been there too—early projects had little lags because of bridge calls, but with JSI the system got a lot smoother. When you start a new project, pay attention to the React Native version and whether the libraries you’ll use are JSI‑compatible; it matters for performance.