Overview
Function-as-a-Service, or FaaS, is a cloud computing model where developers write individual functions that run only in response to events. It is a core component of serverless computing. With FaaS, the cloud provider handles all infrastructure tasks, such as provisioning servers, scaling, and maintenance, while developers focus only on writing and deploying code.
What Problem Does It Solve?
Traditional applications require servers to be running at all times, even if they are idle. This leads to wasted resources and higher costs. FaaS solves this by executing code only when triggered, so organisations pay only for the compute time actually used. It also removes the burden of managing servers and scaling infrastructure.
How It Works
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Event triggers: Functions are activated by events such as HTTP requests, database changes, or file uploads.
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Ephemeral execution: Functions run for a short duration and shut down automatically after completion.
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Automatic scaling: The cloud provider runs as many instances of the function as needed, depending on demand.
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Stateless model: Each function call is independent, so state must be managed externally in databases or storage.
Everyday Benefits
- Cost savings by paying only for executed functions.
- Faster development cycles with simpler deployment.
- Easy integration with APIs and event-driven workflows.
- Built-in high availability managed by the provider.
Deployment Considerations
Popular FaaS platforms include AWS Lambda, Azure Functions, and Google Cloud Functions. While highly efficient for event-driven workloads, FaaS is less suitable for long-running tasks, workloads requiring low latency at all times, or applications that need persistent state. Many organisations use FaaS as part of broader serverless and microservices strategies.
