Preview Environments

A preview environment is a temporary, fully running copy of your app, built from the branch of an open pull request. Open a PR against a repository connected to a service that has previews enabled, and ZenSailor builds that branch and deploys it under its own generated domain — so the change can be clicked through before anyone merges it.

Previews are available on the Pro and Enterprise plans, and need a wildcard DNS record pointed at your instance before they can be enabled — set Preview Environment Domain under Settings → General, then point *.your-preview-domain at the node. Until that is configured the per-service toggle stays disabled.

What gets created

A dedicated environment inside the same project, containing a copy of every preview-enabled service, each pointed at the PR branch. Pushing more commits to the pull request redeploys it.

When it goes away

When the pull request is merged or closed. A preview that sees no activity for 14 days is also removed automatically, so a missed webhook — a deleted fork, an archived repo — never leaves an environment running forever.

Your data is safe

A preview never inherits the real service's volumes. It starts with an empty data directory, so a pull request cannot read or corrupt production data. A service with managed volumes will come up empty in preview — seed it from the app, or point the preview at an external database.

Previews are never held by a deploy window. A preview exists to make a pull request reviewable; holding it until the next window would defeat the point of building it.