system 7

7 Articles

Mac System 7 On A G4? Why Not!

December 5, 2025 by 13 Comments

Over the many years Apple Computer have been in operation, they have made a success of nearly-seamlessly transitioning multiple times between both operating systems and their underlying architecture. There have been many overlapping versions, but there’s always a point at which a certain OS won’t run on newer hardware. Now [Jubadub] has pushed one of those a little further than Apple intended, by persuading classic Mac System 7 to run on a G4.

System 7 was the OS your Mac would have run some time in the mid ’90s, whether it was a later 68000 machine or a first-gen PowerMac. In its day it gave Windows 3.x and even 95 a run for their money, but it relied on an older Mac ROM architecture than the one found on a G4. The hack here lies in leaked ROMS, hidden backwards compatibility, and an unreleased but preserved System 7 version originally designed for the ’90s Mac clone programme axed by Steve Jobs.  It’s not perfect, but they achieved the impossible.

As to why, it seems there’s a significant amount of software that needs 7 to run, something mirrored in the non-Mac retrocomputing world. Even this hack isn’t the most surprising System 7 one we’ve seen recently, as an example someone even made a version for x86 machines.

Thumbnail Image Art: Apple PowerMac G4 by baku13, CC BY-SA 3.0

Macintosh System 7 Ported To X86 With LLM Help

September 29, 2025 by 51 Comments

You can use large language models for all sorts of things these days, from writing terrible college papers to bungling legal cases. Or, you can employ them to more interesting ends, such as porting Macintosh System 7 to the x86 architecture, like [Kelsi Davis] did.

When Apple created the Macintosh lineup in the 1980s, it based the computer around Motorola’s 68K CPU architecture. These 16-bit/32-bit CPUs were plenty capable for the time, but the platform ultimately didn’t have the same expansive future as Intel’s illustrious x86 architecture that underpinned rival IBM-compatible machines.

[Kelsi Davis] decided to port the Macintosh System 7 OS to run on native x86 hardware, which would be challenging enough with full access to the source code. However, she instead performed this task by analyzing and reverse engineering the System 7 binaries with the aid of Ghidra and a large language model. Soon enough, she had the classic System 7 desktop running on QEMU with a fully-functional Finder and the GUI working as expected. [Kelsi] credits the LLM with helping her achieve this feat in just three days, versus what she would expect to be a multi-year effort if working unassisted.

Files are on GitHub for the curious. We love a good port around these parts; we particularly enjoyed these efforts to recreate Portal on the N64. If you’re doing your own advanced tinkering with Macintosh software from yesteryear, don’t hesitate to let us know.