Lambda Function
lambda, aws lambda, lambda functions, cloud function, serverless functionDefinition
AWS Lambda — a single function deployed on its own, invoked by an event (an HTTP request, a queue message, a file landing in a bucket, a schedule), run in a container the platform creates and discards
The generic noun that became a product name and then went back to being a generic noun: Google calls them Cloud Functions, Azure calls them Functions, and everyone says lambda. Two properties drive every design decision around them — a cold start on the first invocation after idle, and a hard execution timeout, which together rule out long jobs and make a queue the usual answer for work that does not fit.
One function, one event, one short life.
Avoid: treating it as a place to put a whole application. A lambda that grew a router, a database pool and a warm cache is a server with a timeout and a worse deployment story. The unit is small on purpose.