How Ramp built a full context background coding agent on Modal

Ramp built an internal background coding agent called Inspect on top of Modal Sandboxes, which now authors over half of all merged pull requests at the company. Each session spins up a full-stack development environment (Postgres, Redis, Temporal, RabbitMQ) in seconds using filesystem snapshots refreshed every 30 minutes, giving engineers, PMs, and designers access to a complete dev setup without any local configuration. The agent runs OpenCode alongside a VS Code server, web terminal, and a VNC/Chromium stack for visual verification, and integrates with GitHub, Slack, Buildkite, Sentry, and Datadog. Modal's distributed primitives—Cron, Dicts, and Queues—handle scheduling, session coordination, and multi-client routing, enabling hundreds of concurrent isolated sessions. The result: 80%+ of Inspect itself is now written by Inspect, and non-engineers can ship code directly.