Feature · Build & deploy
Preview deployments for every pull request.
A preview deployment is a live, temporary copy of your app built from a pull request. Open a PR on GitHub and Runex deploys that branch to its own HTTPS URL, so you test the change before it reaches production.
- One URL per pull request
- Rebuilds on every push
- Removed when the PR closes
- pull request
- #42 · add checkout flow
- branch
- feat/checkout
- env
- preview variables
- runtime
- isolated container
- status
- live
- preview
- https://storefront-pr-42.runex.cloud
Definition
What is a preview deployment?
A preview deployment is an isolated, short-lived deployment of a pull request, served on its own URL. It runs the same build and runtime as production without touching production traffic.
Reviewers click a link instead of pulling the branch and running it locally. Designers, product managers, and QA all see the same working version.
On Runex, each preview runs in its own isolated container with its own HTTPS URL, and it uses the environment variables you set for previews, so a test branch never writes to your production database.
Previews are temporary. When the pull request is merged or closed, Runex removes the preview deployment.
How it works
How do preview deployments work on Runex?
Open a pull request, get a URL. Runex handles the build, the container, and the cleanup.
-
You
Open a pull request
Push a branch to your connected GitHub repo and open a PR.
-
Runex
Build the branch
The PR's latest commit is built like a production deploy.
-
Runex
Share a preview URL
The PR gets its own HTTPS link to review and test.
-
Runex
Clean up on merge
Merge or close the PR and the preview is removed.
Benefits
Why use preview deployments?
Catch problems before your users do. Every change gets reviewed running, not just read.
Review the real thing
Test a working URL on any device, no local setup.
Protect production
Previews are isolated and use separate env variables.
Update on every push
New commits to the PR rebuild the same preview.
Merge with confidence
Know the branch builds and runs before it ships.
Compare
Preview deployment vs staging environment: what's the difference?
A preview is per change; staging is shared. Previews come and go with each pull request, while staging is one long-lived copy that every change lands in.
| Preview deployment | Staging environment | |
|---|---|---|
| Lifespan | As long as the pull request | Always on |
| Scope | One branch, one change | Many changes mixed together |
| Conflicts | None: each PR is isolated | Changes can collide |
| Best for | Reviewing a single change | Final checks before a release |
Example
Example: reviewing a checkout redesign
A designer reviews a new checkout flow on a live URL before it merges.
- A developer opens PR #42 on acme/storefront
- Runex builds feat/checkout in an isolated container
- The PR gets a preview HTTPS URL
- The designer tests checkout on phone and desktop
- A fix is pushed: the same preview rebuilds
- The PR merges; production deploys and the preview is removed
- pull request
- #42
- commits
- 3 · latest built
- database
- DATABASE_URL = preview db
- reviewers
- design, qa
- status
- live
- on merge
- preview removed
What is the difference between a deploy preview and a branch deploy?
A deploy preview is tied to a pull request and disappears when it closes. A branch deploy tracks a branch continuously. Runex creates previews per pull request.
Do preview deployments use production data?
They shouldn't. Give previews their own environment variables, for example a separate DATABASE_URL, so tests never touch production data.
How long does a preview deployment last?
Until its pull request is merged or closed. New commits update the same preview; closing the PR removes it.
Can I get preview deployments from GitLab or Bitbucket?
Not on Runex. Preview deployments work with GitHub repositories connected through the Runex GitHub App.
Next step
Ship with preview deployments today.
Sign up, install the GitHub App, and deploy your first app. It's free to start.