StartupY Combinator (S25)
Twill
Build locally, delegate to the cloud: runs Claude Code and Codex in cloud sandboxes and returns pull requests.
Twill runs coding agents such as Claude Code and Codex in cloud sandboxes, so a developer can hand off a task from their machine and get a pull request back ("Build locally. Delegate to the cloud."). It is a Y Combinator S25 company and launched on Hacker News in April 2026.
Neighbours in the directory
San Francisco, CA · Est. 2023
Devin, the AI software engineer, and the Windsurf IDE.
Cognition builds Devin, an autonomous AI software engineer that plans and executes engineering tasks end-to-end, and acquired the Windsurf agentic IDE in 2025. One of the defining startups of the coding-agent wave.
~$10.2B valuation (Sep 2025)
Prague, Czechia · Est. 2023
Open-source sandboxes for running AI-generated code.
E2B gives agents secure, isolated cloud micro-VMs to execute code and commands — the execution runtime layer of the harness, used by many coding and data-analysis agents.
Est. 2023
Elastic sandboxes for running AI-generated code.
Daytona provides secure, OCI-compatible sandbox 'computers' that spin up in under 90ms — with snapshots for persistent agent state. In 2026 it moved core development to a private codebase while continuing to run as a commercial platform.
Connections
Relations from the Harness Hub knowledge graph, as charted in the State of Harness reports.
Built on · 2
- Claude CodeProject
- CodexProject
Similar entries · 1
- TemboStartup
Sources
Verified Oct 29, 2026