NestJS
Dependency injection, request lifecycle, validation, and database integration.
How should Nest handle jobs and scheduled tasks?
A background job moves work out of the immediate request path, while a scheduled task starts work at a chosen time. Nest can integrate with queues and schedulers, but reliable execution still requires durable state and coordination. Multiple app instances can run the same schedule unless one owner or a distributed coordination mechanism is used.
What are WebSockets, microservices and CQRS used for?
WebSockets maintain a two-way connection for ongoing messages, microservices split an application into separately operated services, and CQRS separates command/write handling from query/read handling. These solve different problems and can be used independently. Each adds complexity that should be justified by a concrete requirement.
How do I test and deploy a Nest app?
Testing a Nest application means verifying business rules, framework wiring and real integrations at suitable levels. Deployment then packages that verified application with configuration, health checks and lifecycle handling. Mock-only tests cannot prove the database constraints or authentication chain behave correctly.
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