Serverless Architecture

Serverless architecture is a cloud-computing model where developers deploy code without managing servers. The cloud provider runs code in response to events, automatically allocates resources, and bills only for actual execution time in milliseconds. Physical servers still exist, the "serverless" label means operational responsibility shifts entirely to the provider.

Serverless removes upfront infrastructure cost. Teams launch features with a single upload, and the platform scales from one request to thousands automatically. No over-provisioning (wasted budget) and no under-provisioning (outages). Billing ties directly to usage. AWS Lambda, Google Cloud Functions, and Azure Functions are the major platforms.

The model favors event-driven designs where functions react to HTTP requests, file uploads, database changes, or message queues. This creates more modular systems and speeds up iteration.

The tradeoffs are cold-start latency (functions that have not run recently take longer to boot), vendor lock-in, debugging complexity, and execution time limits that make serverless unsuitable for long-running computations.