September 2022 Status Update

Binary package support you say?

All the new binary packaging support is contained in Briefcase 0.3.10.

On Android, binary module support was achieved by moving to Chaquopy as a base for Android projects. Along with support for binary modules, this change has the added benefit of faster startup times, and less bugs at runtime. This means you'll need to re-generate any Android project - the Python source code should work as-is, but there's no simple way to convert the Android Gradle project from the older Rubicon base to the newer Chaquopy base.

On iOS, we've reworked how the support packages are constructed, and added support for installing binary modules from a Beeware-specific package repository that includes builds of iOS binary wheels. We've also added asset signing to the iOS Xcode project - and applied the same changes to the macOS backends. Of course, this also means you'll need to re-generate any iOS project to take advantage of these changes.

While we are now able to support binary packages on mobile platforms, this doesn't mean that every binary package is automatically supported. Binary wheels need to be compiled for mobile platforms, and compiling for mobile platforms can be complicated. However, we've compiled ~40 of them most popular packages with binary components (including numpy, pandas, cryptography, pillow and matplotlib), and made them available as dependencies. In order to get working builds, some of these packages are slightly older versions (e.g., cryptography is a version from before the introduction of the rust dependency); however, we've endeavoured to provide the most recent versions possible.

A full list of supported packages can be found on the Chaquopy package repository for Android, and the BeeWare repository for iOS. If your project uses one of these packages, you only need to add them to the requires definition in your pyproject.toml, then update and re-build your project, and you're done.

If there’s a package you want that isn't on this list, you'll need to request a binary wheel. For Android, open a ticket on the Chaquopy repository. For iOS, open a ticket on this repository. If you're adventurous, you can also try building wheels yourself. The issue trackers are on a project that has as "forge-like" tool for building wheels, in the server/pypi folder; there are tools and documentation describing how to build a package. The use of these projects is a short-term measure; in the longer term, we want to move to an actual “forge”-style community-managed model for managing binary packages.