Glossary term
What is Cold start? Meaning for developers
In System Design
Extra delay when a serverless function starts fresh. Example: First request after idle takes 1 second.
Learn it properly · System DesignLesson 57: Cloud Fundamentals: Regions, AZs & ServerlessServers that once took months to order now take minutes — but the cloud has its own concepts, failure modes and surprise bills. Regions and availability zones, IaaS to SaaS, serverless and cold starts, the shared responsibility model, cost, and infrastructure as code.In Scenario Debugging
The extra wait when a serverless function or an idle container handles its first request.
Learn it properly · Scenario DebuggingLesson 2: “The UI Is Fast but the API Takes Too Long”: How to Solve ItFollow the request: DNS and TLS, cold starts, N+1 queries, missing indexes, slow calls to other services, big payloads and missing caches. Then the UX fixes while the backend is repaired.