Since Mac OS 9 doesn’t have out-of-the-box support for modern secure networking protocols, you often have to go through a proxy, which is pretty painful. I wanted to make it possible for an old Mac to connect to modern web services on its own.
There are also two related projects for connecting to Bluesky and Mastodon:
https://yllan.org/software/PlatinumSky/ https://yllan.org/software/Palaeomastodon/
Those also add emoji text rendering, since emoji have become such an important part of modern internet culture. Mac OS 9 does support some early Unicode, but it is, after all, nearly 30-year-old software, so that support is naturally incomplete.
The main reason I chose Mac OS 9 is that these modern services are actually fairly demanding for old machines: parsing JSON instead of a more compact binary format, handling generally large images, doing cryptographic computations, and so on. I think 68k machines would probably struggle too much. If the goal is to run independently without relying on a proxy, you really need something with relatively modern specs.
BTW, I haven’t actually run this on real hardware either. I used QEMU during development. I do have an iBook G4 signed by Woz, but it stopped booting a few years ago.
I’d also like to thank bbenchoff’s MacSSL:
https://bbenchoff.com/pages/MacSSL.html
and cy384’s opentransport-mbedtls:
https://github.com/cy384/opentransport-mbedtls
Both were a big help.