Topic
Definition
A Next.js deployment builds the application into a production artifact with environment-specific configuration and runtime constraints.
In simpler words
Production is a separate environment: it needs the right build, public values, cookies, and API connection—not just a working local server.
The deployed web app must communicate safely with the separately deployed Nest API without exposing secrets.
Run the production build before release to catch route, type, and bundling failures that development mode may not surface. The host must support the Next runtime capabilities that the application uses.
Variables prefixed NEXT_PUBLIC are embedded for browser use at build time. Never place database credentials, JWT signing values, or internal service secrets behind that prefix.
// Safe for browser exposure
NEXT_PUBLIC_API_ORIGIN=https://api.example.com
// Server-only — never NEXT_PUBLIC
JWT_SECRET=...
DATABASE_URL=...The naming convention signals whether a value becomes visible in the client bundle.
// Wrong conclusion: “cookie auth worked on localhost, so deployment is ready”
// Right: verify HTTPS, SameSite, Secure, domain, credentials, and Nest CORS in staging.Cookie behavior depends on the deployed origins and browser security context.
Definition
The Next deployment and Nest deployment have separate artifacts but one user journey.
In simpler words
Validate their origins, credential policy, and failure behavior together before calling the release complete.
Use deployment-specific environment configuration rather than committing environment files.
Check the deployed app with a real browser to confirm login, ticket reads, ticket writes, and logout.
Live playground
Classify each environment variable as browser-safe or server-only.
Verify cookie + API origin settings in production.
next-deploying
Test
At least 10 questions — mix of concept, syntax, practical, and logic. Score ≥ 80% (enforced by the API) to save progress.
Checking your session…
10 questions · concept 3 · syntax 2 · practical 3 · logic 2