Retro MultiOSE — one native (soon on windows) macOS app for QEMU, Basilisk II, and SheepShaver

[okyproxd]

Hey all — long-time reader, first-time poster. Wanted to share something I've been building: Retro MultiOSE, a native SwiftUI front-end that wraps QEMU, Basilisk II, and SheepShaver behind one clean interface, so you're not juggling separate apps and config files for each system you want to run. The whole idea was to make switching between eras feel effortless. Instead of hunting down separate emulator binaries, memorizing command-line flags, and hand-editing prefs files for each system, you get one native Mac app with a proper tabbed interface. Setup is where you import ROMs, boot CDs, and hard disks. Machines is where you configure and launch each virtual system, pick a CPU speed preset, and run it — and you can have multiple machines running side by side without losing track of any of them. Save States lets you name a snapshot, come back later, and load right back into it instantly, built on QEMU's native savevm/loadvm. RAM goes from 128 KB, if you're feeling authentic about a real Mac 128K, all the way up to 8 GB. It's meant to feel like a real Mac app rather than a wrapper around a terminal — point it at your media, pick your OS, hit Run. Right now in v0.1.0, Windows XP installs and boots cleanly, Mac OS X 10.0–10.5 runs through QEMU's PowerPC backend (Leopard is fully installed and booted on my end), and Mac OS 9.1 also runs through QEMU PowerPC — no ROM required at all, it boots straight through Open Firmware. In case anyone was wondering, the QEMU PowerPC emulator should be able to emulate Mac OS 9.0 - 9.2.2, and also Mac OS X 10.0 - 10.5. QEMU x86 emulator should be able to Windows 95 - XP (not important, this is not a vintage windows forum) and also mostly any Linux distro. SheepShaver should be able to emulate 7.5.3 - 9.04 (if using old world ROM, if using new world ROM, 8.5 - 9.04.) And finally, Basilisk II should emulate System 6 through Mac OS 8.1. In the future, I aim to test as many OSs as possible to let you guys know if all of them are compatible with my app. Two things aren't solid yet, and I want to be upfront about them. Basilisk II reliably reads valid ROMs and disks but hangs a few seconds into boot on Apple Silicon — this reproduces across different ROMs and isn't fixed by the usual ignoresegv/idlewait/jit false flags. If anyone here has fought this exact issue on M-series Macs, I'd love to compare notes. And with SheepShaver, I learned the hard way that Blue & White G3 ROMs aren't supported by SheepShaver at all — that's a real, documented limitation rather than a config issue. Beige G3 or Old World ROMs are the way to go there. GitHub repo with downloadable .dmg file @: https://github.com/okyproxd/retromultiOSE Would genuinely appreciate any input, especially on the Basilisk II hang — feels like exactly the kind of thing this community has seen before. Working on this app a lot while travelling; stay tuned for future updates, and hopefully getting Basilisk II and SheepShaver up and running. Also I am currently testing Mac OS X versions 10.0 and 10.4 in QEMU PowerPC emulator, but as it seems, those should both also work perfectly fine. And finally, because on travel at the time of starting the making of this app with XCode and a MacBook Air, I am unable to make and/or test a Windows .exe version, but at home with my PC I will be sure to push that out ASAP!

 

[okyproxd]

Please make sure to check out my GitHub page, and even try my app out!