Docs
Environments
Last updated:
Environment variables supply configuration to your build and running application. Choose the correct scope and apply changes deliberately.
Variable scopes
| Scope | When it is used |
|---|---|
| Build | During image/application build; changing it requires rebuilding. |
| Runtime | When the application runs; apply the updated configuration to the running service. |
| Both | Provided at build time and runtime. |
Add or update variables
- Open the application’s variables area. Add the key and value expected by your code.
- Choose Build, Runtime or Both. Mark sensitive values as secrets.
- Save, then follow the product’s apply or redeploy action. Confirm that the resulting deployment uses the intended values.
Public values and secrets
Use separate values for development and production. A variable named DATABASE_URL is an example, not a requirement for every framework.
Releases and recovery
Changes to variables are not a substitute for testing a release. Inspect deployment history and health after changes. If using rollback, check that the target deployment is eligible and that its configuration and database schema remain compatible.
Ready to deploy your application?
Start for free