Fetch response implementations benchmark for React Native

Recreated benchmarks from this tweet on X to compare:

• RN built-in fetch
• Expo fetch
• react-native-nitro-fetch

Benchmarks

All benchmakrs are defined in benchmarks/index.ts.

Methodology

• JSON payload: Used 50MB json from this page. It should be placed in the fixtures/ directory.
• Localhost hosted to mitigate networking impact (some libraries do proecessing during the await fetch() call instead of await response.<<desiredFormat>>() so networking time could not be fully separated.)_
  • Used cd fixtures && python3 -m http.server (or bun run serve) for simulator/Localhost.
  • Used PocketServer app on physical iOS.
  • The app is also available on Android.

Sample results

Some random results are available in the screenshots directory.

Patched files

In the patches there are two patches:

• expo - added zero-copy arrayBuffer2() to compare memory copying cost
• expo-modules-core - (needed for the above) implementations for native ArrayBuffers that have not been released yet.

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This is an Expo project created with create-expo-app. App UI was vibe-coded.