Susan Githaiga Lands Code in Bitcoin Mining Firmware Mujina

On August 31, Ryan Kuester merged a small change from Susan Githaiga into Mujina, the open‑source Bitcoin mining firmware he designs and maintains. It removed an outside software library the firmware no longer needed.

Dada Devs, where she trained, celebrated her on October 9 "for becoming the first African contributor to the 256 Foundation's mining project."

On October 1, the 256 Foundation, which funds Mujina, had already named her among five people who "landed code this term, most of them for the first time."

Here's what Susan changed, what Mujina does for miners and where she learned to build for Bitcoin.

How Susan Githaiga Improved Mujina's Code

Susan Githaiga Lands Code in Bitcoin Mining Firmware Mujina — photo Mujina sends messages to the BM13xx chips inside mining machines and checks them with two kinds of checksum called CRCs. Until August, it borrowed that maths from crc_all, a small library kept by a single maintainer. Susan's pull request replaced it with two short functions written into Mujina itself, each about 10 lines long.

Nothing else in Mujina had to change. She tested the new code against the old library, and it gave the same results. The fix closed one of the clean‑up jobs the project listed after auditing the outside code it depends on.

That audit is part of how Mujina guards its supply chain. The project locks its dependencies and checks them regularly, and when the arrayref supply‑chain attack moved through the Rust ecosystem in August, it published its finding: not affected.

What Is Mujina? The 256 Foundation's Open‑Source Bitcoin Mining Firmware

Firmware is the layer that talks to a miner's chips, and on almost every machine shipping today it is closed. "You cannot prove it is not skimming your hashrate or phoning home to a license server for permission to mine," the 256 Foundation writes.

Mujina is meant to replace that with one open codebase that runs hashboards from any vendor, with no dev fee. It is written in Rust and released under the GPL.

The 256 Foundation is a US nonprofit that pays the core contributors building an open‑source Bitcoin mining stack. Mujina already runs on the Bitaxe Gamma, an open‑source single‑chip miner. On October 1, the foundation extended its funding through December 2026 so owners of Antminer S19j Pro and S19k Pro machines can install Mujina with a flashing app, and it expects that to bring the project more contributors.

Dada Devs: Training Africa's First Generation of Female Bitcoin Developers

Dada Devs calls itself the "home of Africa's first generation of female Bitcoin developers." It was founded by Lorraine Marcel, who also started Bitcoin Dada. The programme trains African women engineers in Bitcoin and Lightning development, with a focus on real commits and pull requests.

Susan is one of several Dada Devs alumni whose code now shows up in Bitcoin projects, according to their own accounts on the Dada Devs site:

Mercy Mbao had a pull request merged into the Lightning Network Gallery under BitDevs Nairobi, runs functional and unit tests in Bitcoin Core and mentors Cohort 3 as a peer lead.