ukoOS

ukoOS is a small post-Unix OS being developed by the UKO student group at the University of Minnesota. Currently, it only targets RISC-V devices.

Check it out on GitHub or read the documentation.

UKO regularly meets in-person. Attend one of these meetings to get involved; ask whoever seems like they’re in charge how to get started.

As of Spring 2026, we meet at 6:30pm in room 3-125 of Keller Hall.

If you want to jump right into the code, the issue tracker has a “good first issue” label. It’s still probably best to ask an existing contributor about taking on one of these issues, but you can do so by commenting on the issue.

You can join the UKO Discord too, although some development activity is moving to IRC. You can find us on IRC in the #uko channel of chat.remexre.com.

In the future, we might set up a web IRC client to make this easier for those new to IRC. If you’re interested in using this or helping set this up, please contact us.

Links

• ukoOS Documentation
• GitHub
• U-Boot fork

Slides

• 2026-01-28: UKO Spring Kickoff (Spring 2026)

For convenience, we host and link to a lot of documentation that is helpful for ukoOS developers here.

Documentation and Specifications

Milk-V Duo S

• SG2000 technical reference manual
• OpenC906 user manual

Milk-V Jupiter

• SpacemiT K1 documentation
• SpacemiT K1 datasheet

Peripherals

• MSP4022
• NS16550A
• 8250 UART Programming on Wikibooks

RISC-V

• RISC-V ABI 1.0
• RISC-V Advanced Interrupt Architecture 1.0
• RISC-V IOMMU Architecture 1.0.1
• RISC-V PLIC Specification 1.0.0
• RISC-V Privileged Architecture 20250508
• RISC-V Supervisor Binary Interface Specification 3.0
• RISC-V Unprivileged Architecture 20250508
• RVA23 Profiles 1.0

Other standards

• Devicetree 0.4

Papers

• Daan Leijen, Benjamin Zorn, and Leonardo de Moura. 2019. Mimalloc: Free List Sharding in Action. Microsoft Technical Report MSR-TR-2019-18. Microsoft Research.