Jeff Geerling Builds a Working Macintosh for $20 Using a Raspberry Pi Pico

How much computer can you squeeze out of a four-dollar microcontroller? Enough to run a classic Macintosh, apparently. Jeff Geerling, the prolific hardware tester and Pi enthusiast, published a build on March 2 demonstrating a fully functional Macintosh running on a Raspberry Pi Pico — and the entire project costs about twenty dollars in parts.

The Build Details

The project uses Matt Evans' Pico Micro Mac firmware running on the RP2040-based Raspberry Pi Pico. The setup includes a JCM PicoMicroMac v2 adapter board, a microSD card HAT adapter for storage, and a small 5-inch VGA monitor. The system outputs to a 640x480 VGA display at 60 Hz with full USB keyboard and mouse support.

Here is the fun specification detail: the Pico Micro Mac provides 208 KB of RAM. That is 63 percent more than the original 128K Macintosh shipped with in 1984. A four-dollar chip from 2021 outperforms a machine that cost $2,495 when it launched — adjusted for inflation, that is roughly $7,500 in today's dollars.

Why Retro Computing on Modern SBCs Matters

Projects like this are more than nostalgic curiosities. They demonstrate just how much capability the RP2040 chip packs into an incredibly affordable package. The Pico was designed for microcontroller applications — sensor reading, motor control, simple automation. Running an entire operating system with a graphical user interface pushes the chip well beyond its intended use case, and the fact that it handles the task smoothly speaks to the quality of both the hardware and the community firmware.

For educators, this build offers a tangible way to teach computer science history. Students can interact with the same interface that launched the personal computing revolution, running on hardware cheap enough to provide one per student. The simplicity of the build — no soldering required beyond the adapter boards — keeps it accessible to beginners.

The RP2040 Community Keeps Pushing Boundaries

The Raspberry Pi Pico has become a playground for creative engineering projects precisely because it sits at the intersection of cheap, capable, and well-documented. The community has built everything from game consoles to synthesizers to network analyzers on the platform. Each project expands the reference library for what the chip can do, lowering the barrier for the next builder.

Geerling noted that the build took about thirty minutes from unboxing to a working Macintosh desktop. That combination of speed, cost, and fun factor makes it an ideal weekend project for anyone curious about retro computing or looking for a conversation-starting desk accessory.

Sometimes the best hardware projects are the ones that make you smile. A twenty-dollar working Macintosh definitely qualifies.

Sources: Jeff Geerling Blog, March 2, 2026; Hackaday, March 2026