Boot up classic Mac OS in your browser window with the “Infinite Mac” project

For retro computing enthusiasts, there's no substitute for unearthing ancient hardware and computing like it's 1999. But as with old video games, emulation offers a much more convenient way to run old software. Now, running System 7 or Mac OS 8 on a virtual 68k Mac is more convenient than ever, thanks to a clever project dubbed "Infinite Mac."

What makes the project unique isn't necessarily the fact that it's browser-based; it has been possible to run old DOS, Windows, and Mac OS versions in browser windows for quite a while now. Instead, it's the creative solutions that developer Mihai Parparita has come up with to enable persistent storage, fast download speeds, reduced processor usage, and file transfers between the classic Mac and whatever host system you're running it on. Parparita details some of his work in this blog post.

Beginning with a late 2017 browser-based port of the Basilisk II emulator, Parparita wanted to install old apps to more faithfully recreate the experience of using an old Mac, but he wanted to do it without requiring huge downloads or running as a separate program as the macintosh.js project does. To solve the download problem, Parparita compressed the disk image and broke it up into 256K chunks that are downloaded on demand rather than up front.