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AppendixHow previews work
Opened or updated
A new pull request or a new push to it deploys or redeploys a preview copy automatically.
Closed
Closing a pull request tears the preview down regardless of whether it merged.
Status back to your git host
On GitHub, each preview shows as a deployment in the preview environment that moves from in progress to success or failure.
Disposable databases
An app can provision a full, disposable database for every pull request preview that is destroyed with the preview.
Multi-service previews
A multi-service app fans a preview out the same way a real deploy does, never through a second, drifted code path.
Four git providers
GitHub, GitLab, Bitbucket and Gitea sources all support previews.
Frequently asked questions
Which git hosts support previews?
Which git hosts support previews?
GitHub, GitLab, Bitbucket and Gitea.
Are previews on by default?
Are previews on by default?
Previews are gated on a per-app preview setting, so you turn them on where you want them.
What about secrets in previews?
What about secrets in previews?
Previews use the app’s configuration, so review which environment values a preview should receive before enabling it for untrusted forks.
Is this the same as deploy thumbnails?
Is this the same as deploy thumbnails?
No. Deploy previews, the thumbnails in deploy history, are a separate feature from per-pull-request preview environments.