Idea: a reproducible-release checker for React Native split APKs

[AmineYagoub]

The problem. Splitting a React Native app into one APK per processor, plus a universal one, is easy to configure and easy to get wrong:

• stale outputs left from an earlier build;
• version codes that clash between APKs;
• an APK carrying the wrong processors;
• missing licence notices;
• two builds that should match but don't.

F-Droid and anyone verifying reproducibility need every one of these right.

What we did. Minhajna's tools/android/release-apks.js (djazairdev/minhajna#105, 114 lines, Node built-ins only) checks a release build folder:

• exactly the universal, armeabi-v7a and arm64-v8a APKs, and nothing else, matching output-metadata.json;
• each version code follows the scheme: base × 10 + 0, 1 or 2;
• each APK holds only its own processors' native libraries;
• the bundled fonts and licence notices are present, including a generated notice compared with the licence file;
• compare checks two independent builds byte for byte.

For 0.1.0, two macOS builds and CI's two Linux builds matched exactly (djazairdev/minhajna#208).

Who else it hits. React Native apps going to F-Droid, apps with reproducible-build claims, and anyone running split APKs through CI.

What to build

• A configurable CLI and GitHub Action, rn-release-check. A config file would set the processors, the version-code scheme, required assets and notices. It would run verify on one build and compare across two, with clear messages for each failure.
• It would pair with Idea: keep React Native native libraries to the processors you ship #3 (narrowing the native libraries) and Idea: check a signed APK against its rebuild, with no dependencies #5 (checking a signed APK).

Size: medium. It means generalising Minhajna's script, plus a sample app and CI. MIT.

From Minhajna's work; drafted with Claude Code.