Variables: The Right Way to Configure a Deployed Service
A deployed service needs configuration — API keys, database URLs, feature flags — and how you manage that configuration is a genuine security and maintainability decision, not an afterthought.
Never commit real secrets to your repository. The same rule from this platform's other tracks applies with full force here: an API key or database password committed to Git — even in a private repository — is a real, lasting exposure. Railway's Variables tab exists specifically so secrets never need to live in your code at all.
Set variables under a Service's Variables tab. Key-value pairs, injected into your running process as actual environment variables — read the same way your application would read any environment variable locally (process.env.DATABASE_URL in Node, os.environ in Python), no Railway-specific SDK required just to read them.
Changing a variable triggers a redeploy. Railway restarts your service with the new value applied — there's no separate "apply" step or manual restart required, though it does mean a variable change has the same brief interruption a normal deploy would.
Raw Editor lets you paste a whole .env-style block at once. Rather than adding variables one at a time through the UI, the Raw Editor accepts a full block of KEY=value lines — genuinely faster for initial setup of a service with many variables.
Variables are scoped per-Environment, not shared globally by default. Your production and staging Environments (from the Welcome course) can — and usually should — have different values for the same variable name (different database URLs, different API keys) without any risk of one leaking into the other.
Why this matters for you
Treating configuration properly from day one — never in code, always in Railway's Variables — is the difference between a genuine security practice and a real exposure waiting to be discovered in your Git history.
▶️ Before the next lesson
Open your Railway service's Variables tab and add one real environment variable your application actually reads (even something simple) — confirm the service redeploys and picks it up correctly.