Complete Guide to preview.yaml

The preview.yaml file is the heart of Previewhost. It describes which services to start, how they depend on each other, and where secrets come from.

Basic structure

Define services under the services key. Each service can have a command, port, and depends_on list.

Databases

Use type: postgres or type: redis for managed instances. Previewhost handles data isolation automatically.

Secrets

Reference secrets instead of hardcoding them. They stay outside of agent conversations.