Android API level 29 breaks support for executing data that didn't ship with the app (IIUC), so Termux cannot work with API level 29 without major changes and complications, and Nix-on-Droid cannot realistically work at all.

Android 10 doesn't strictly require API level 29, it merely supports it.… seems to imply that while Play requires API level 28 (Android 9) or higher for all new apps and all upgrades, Android itself still accepts at least as low as API level 22 (Android 5.1).

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