Story · Cline
How We Migrated 11 Million Users to Cline's Biggest Refactor (Cline)
blog post · Story page
Cline pulled its agent harness out of the VS Code extension into a shared SDK, then had to move an extension installed by over 11 million developers onto it. The first attempt took months and was rolled back immediately, and with no gradual rollout in the VS Code Marketplace, Cline built its own release process.
In plain words
- Cline moved its Visual Studio Code extension onto a shared software foundation.
- Its first migration took months, broke badly after release, and was immediately reversed.
- The Visual Studio Code Marketplace offered no gradual release option, so Cline built its own controlled rollout process.
- That process compared releases and added production safeguards before exposing all users to the refactor.
- This matters to over 11 million developers whose everyday work could otherwise be disrupted.
Appeared in
- Google's Mantis bug-fixing harness, and privilege escalation in 12 agent harnesses
Sep 03, 2026 · in the sections
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