sandboxd
An open-source, self-hosted engine that spins up an isolated Docker sandbox, runs a coding agent inside it against a prompt, and exposes the resulting app at a live preview URL, through a small Go program and a scriptable /v1 API.
sandboxd is the open-source engine behind prompt-to-app builders such as Lovable, Bolt and v0, made to run on a user's own server. One HTTP request spins up a private, isolated container with its own filesystem and resource limits, runs an AI coding agent inside it against a prompt, and hands the resulting app a live preview URL; idle sandboxes sleep and wake on demand so one machine can hold many apps.
It is deliberately small: one Go program driving Docker, Traefik for routing preview URLs, and SQLite for state, with no Kubernetes, separate database or queue. Every action is a /v1 HTTP call, so a team can build sandboxd into its own product, and an optional web console is itself just a client of that API for creating apps, chatting with the coding agent, watching the live preview, editing files and reviewing a git diff.
The console can also launch existing open-source apps such as n8n, Ghost, Grafana, Metabase, Uptime Kuma and Jupyter with one click.