Today we’re open sourcing deepsec : a security harness powered by coding agents. It runs on your own infrastructure and surfaces hard-to-find issues in large codebases. You can run deepsec on your laptop without setting up a cloud service for privileged source code access. For inference, you can use your existing Claude or Codex subscription without any additional setup. Scanning large repos can take multiple days on a single machine. To run research jobs in parallel, deepsec supports optional fanout to Vercel Sandboxes for remote execution. Scans on Vercel’s codebases routinely scale up to 1,000+ concurrent sandboxes. Link to heading Architecture At its core, deepsec uses claude and codex to perform tailored investigation of a codebase using Opus 4.7 at max effort and GPT 5.5 at xhigh reasoning.…