Infinite Mac, the browser-based project that lets you boot and use vintage Macintosh operating systems from 1984 to 2005, now includes multiple versions of BeOS — the multimedia-focused, multithreaded OS that nearly became the foundation of Apple's next-generation platform. The installs are full-featured: instant boot, streamed disk images, pre-installed software libraries, mountable CD-ROMs from the Internet Archive, and persistent saves. Getting BeOS running required more than dropping in a disk image. Developer Mihai Parparita found a cascade of emulator edge cases in DingusPPC — the PowerPC emulator Infinite Mac already used for classic Mac OS. BeOS's boot loader tripped over ADB keyboard emulation. Screen depth changes exposed assumptions about notification ordering that Mac OS happened to satisfy but BeOS didn't. Early BeOS versions wrote video memory in little-endian mode, a hardware capability DingusPPC hadn't implemented. Later versions correctly enforced HFS data structure rules that Mac OS was lenient about. Each fix was upstreamed, making DingusPPC — now likely the only emulator capable of running PowerPC BeOS — more accurate for all operating systems, not just Be's. The pattern here is instructive: an emulator built against one OS inevitably encodes that OS's quirks as assumptions. Running a second, independently developed OS against the same emulated hardware is one of the best stress tests available. It's the same principle as fuzzing — you learn the most from the inputs you didn't design for. SheepShaver, a Power Mac emulator that originally shipped on BeOS, also needed a fix for an edge case in ROM memory mapping. Parparita's work positions DingusPPC to eventually support MkLinux and Rhapsody as well. Using BeOS in 2026, even through emulation, the speed is immediately striking. It boots fast, windows drag smoothly, and the POSIX terminal feels modern — things its contemporary Mac OS releases couldn't match. The BFS file system with its metadata attributes and live queries still feels like a genuinely interesting idea. But the unfinished quality is equally obvious: bundled apps are technology demos, third-party software rarely got past version 0.1, and the UI — tabbed window titles, a hand cursor, a Deskbar that can't decide whether it's a Start menu or a Dock — reads as a not-fully-coherent hybrid that never had time to resolve its identity. The comparison with NeXTStep, which Apple actually chose, is telling. NeXT supported fat binaries across architectures; BeOS required separate executables per platform. NeXT's file systems were portable; BFS used host endianness, so a PowerPC CD couldn't be read on Intel. These aren't cosmetic differences — they're the engineering maturity gaps that compound when you're trying to build a platform ecosystem. BeOS was fast and innovative in spots, but it was building the plane while flying it. Beyond BeOS, the update adds screenshot and video capture for the emulated screen, expanded OS CD-ROM collections (including Rhapsody and Mac OS X developer previews that DingusPPC can't yet boot), and a migration of archived media to Cloudflare R2 to reduce load on the Internet Archive. An AI coding agent helped with reverse-engineering BeOS's screen resolution persistence format across versions — a pragmatic use of the tool for exactly the kind of fiddly format archaeology it handles well. Infinite Mac remains one of the most impressive solo preservation projects on the web. It doesn't just archive software — it makes it usable, instantly, in a browser, with enough fidelity to form real opinions about what these systems were like to live with. Adding BeOS extends the project from a Macintosh timeline into a genuine counterfactual history machine: here's the OS Apple almost bought, running on the hardware Apple actually shipped. Go use it and decide for yourself whether they made the right call.
