Full Stack developer interview questions

The API checks Redis for a key, returns the value on a hit, and on a miss loads MongoDB then writes Redis with a TTL.

Cache-Control tells browsers and CDNs how long a response may be reused.

TTL is how long a cached entry lives before it expires.

A CDN caches JS, CSS, and images at the edge so users download them from a nearby location.

On pull request you install, lint, test, and sometimes build the React app.

An artifact is the compiled output you ship, such as a Docker image or a React dist folder.

Use separate pipelines or separate jobs with different env secret sets.

A location block matches /api and proxy_pass to the upstream Node port.

try_files looks for a real file and otherwise returns index.html.

Configuration belongs in the environment, not in committed files.

Mongo fits flexible documents and fast iteration when schemas evolve.

An index is a sorted structure that helps find documents without a full collection scan.

Sessions store server-side state and send a session id cookie.

An index on multiple fields matching common filters and sorts.

Backend secrets stay in server env files never committed.

Context or a small store hydrated from /me.

JSON Schema rules on collections catch bad documents.

Shared schema packages or OpenAPI-generated types.

Build static assets, health-check new API instances, drain old ones, then point CDN to new files.

Prefer httpOnly secure cookies with tight CSRF strategy.