Environment Variables

Environment variables let you pass secrets and runtime config to your app — things like API keys, database URLs, and feature flags — without hardcoding them in your repo.

Adding a variable

1. Open the project card and expand the Environment section
2. Enter a Key and Value
3. Click Add

Changes take effect on the next redeploy. Click Redeploy on the project card to apply them immediately, or wait for the next webhook-triggered build.

Updating a variable

Set the same key with a new value. The existing entry is overwritten.

Deleting a variable

Click the × next to the variable in the Environment panel. The variable is removed on the next redeploy.

When variables take effect

Variables are injected into the container at startup. They are not visible during docker build — if your build step needs a secret (e.g. a private package registry token) you need to use Docker build secrets in your Dockerfile.

Accessing variables in your app

Variables are available as standard environment variables:

Node.js

const apiKey = process.env.MY_API_KEY;

// Go
apiKey := os.Getenv("MY_API_KEY")

# Python
import os
api_key = os.environ["MY_API_KEY"]

Reserved variables

Don’t set PORT — WeekendBuilder injects it automatically based on the port you configured for the project. Your app should read PORT from the environment rather than hardcoding it.

Security

Variable values are stored encrypted in the database. They are only decrypted when starting your container. They are never included in build logs or API responses.