make dev, or run
make sandbox NAME=dev to get a shell where that build, its own server, boards and
delivery daemon, and Claude Code, Codex and omp all use folders of their own. Your
installed aboard, your boards and your harness settings are never touched.
make sandbox-update NAME=dev rebuilds and restarts the sandbox on a newer build and
keeps its boards.
The step-by-step guide is in the repository, so it stays next to the code it describes:
Developing with a sandbox.
It covers the daily loop, what is isolated and how, how each harness logs in, adding a
harness so it is sandboxed, and troubleshooting.
To add a harness, see Add a harness.