UFO.ai, a Y Combinator Fall 2026 startup founded by people tied to GitHub Copilot and Perplexity Computer, has released an Apache-2.0 open-source agent operating system that lets teams delegate code and business work from Slack. The company announced the launch on X on Sept. 27, calling UFO "a multiplayer agent harness OS you can build your whole company on," offered either hosted or as open source.
Alex Graveley, who announced the product, put it in plainer terms. "Excited to announce UFO: a new scalable multiplayer agent orchestrator and memory system," he wrote. "We built from scratch to target pain points we saw with people running agent-first businesses."
How UFO works
The product runs through Slack, a web portal and a terminal. Its Slack app page describes it as "an AI assistant that answers questions and completes work from Slack messages." Users add it to a channel and mention @ufo, or send it a direct message. The bot reads thread context and can send and receive files.
For code, data and file work, UFO attaches an isolated computer to the conversation, according to the company's docs. Results must end up somewhere durable, such as a pull request, a file or a hosted asset.
The documented uses range from code changes delivered as pull requests to incident investigation, data analysis, internal app scaffolding and browser chores like filling out forms and downloading files. Recipes in the docs include drafting release notes and assembling board packs. Agents can also run on a schedule or when triggered by an event.
Integrations, models and memory
The docs changelog lists connections to Slack, Gmail, GitHub, Linear, HubSpot, Stripe and GBrain. Users choose a model for each chat, among them Claude, GPT and GLM. An entry covering Sept. 21-27 says Claude Opus 5.5, Sonnet 5.5 and GPT-6 Astra were added "within hours of launch."
A Sept. 10 entry introduced what the company calls "context compaction," which it says "replaces summarization" and "reduces token use and latency by more than 10 times." That figure is the company's own. No independent benchmark has been published that would confirm it.
Memory and file features shipped the same day. Agents can produce Word, Excel, PowerPoint and PDF files, and a memory sidebar shows where information came from. The terminal version installs on Mac, Linux or Windows with a single curl command.
What is actually open
According to the changelog, UFO's core is public under Apache 2.0, including "the agent runtime, its skills, and the model and connector extensions." The third-party tracker githubrepo.cloud showed the ufo-ai/ufo-core repository created Sept. 27, with 94 stars and 12 forks and a last push on Oct. 7. Because that data is weeks old, readers should check the official repository for current figures.
The founders
Graveley's X bio lists him as co-creator of GitHub Copilot, Perplexity Computer, Comet and Dropbox Paper, and a two-time CEO of Hackpad and Minion AI. The company's LinkedIn page says he created GitHub Copilot and later led Perplexity Computer.
Y Combinator's directory, though, names only Marshall Kiely as a founder and gives the team size as two. His listed background includes a stint as Perplexity's finance lead, founding AI engineer at Notable Health, machine learning engineer at Mixpanel, and a Princeton PhD in computational biology. The YC page does not yet mention Graveley. Garry Tan is the YC partner on the company.
Data handling and a caveat
UFO's data processing agreement states that it "will not use Customer Data to train general-purpose AI models." Its subprocessor list, updated Oct. 3, names AWS, Cloudflare, OpenRouter, Fireworks, Baseten, Anthropic, OpenAI, Perplexity, E2B, Browserbase and Slack, among others.
Security teams should read one line closely: "OpenAI processing is not covered by our ZDR commitment," the company says, referring to zero data retention. The legal operator is listed as Metalcraft Inc., a San Francisco company.
A crowded field
UFO enters a market that Y Combinator itself has helped define. YC published Quartermaster, an MIT-licensed multiplayer agent harness that runs in Slack and on the web and that the accelerator uses internally. Open-source alternatives include OpenClaw and Nous Research's Hermes Agent. Microsoft Research has a similarly named UFO project, but it is unrelated.
Pricing, funding and access
UFO.ai has no public pricing, and its site tells visitors to "Book a call." Founderland reported that the founders declined to disclose funding details, and no rounds beyond YC have been made public.
On LinkedIn, the company calls itself "waitlist-only." Its YC listing says the platform "learns your company, goals, tools, and workflows," a promise that, for now, customers will have to test for themselves.
