What Is Serverless?

Serverless Computing is also known as FaaS or Function As a Service.

Function As a Service is an architectural approach in which the resources running your application (CPU, memory, etc.) are fully managed by the cloud provider. You only write your code and specify which events should trigger it, and you pay using a pay-as-you-go model — meaning you only pay for what you use.

A popular example of FaaS is AWS Lambda.

Serverless does not mean there are no servers, or that applications will no longer run on servers. From a software development and management perspective, it is an approach that lets us think less about the concept of servers. It is built on the principle of not worrying about scaling, load distribution, server configuration, error handling, deployment, or even runtime — aiming to run with as few resources as possible and at minimum cost.

We can write a serverless application for every API or task, though I haven’t seen it widely recommended for complex workloads. It seems to be recommended for simple, single-purpose applications. I think it is more suitable for applications that don’t run continuously and wait to be triggered by something — like Alexa, an incoming request to an endpoint, or an application that should run when data is written to a Kafka topic and has a single, simple purpose. In that case, since the job isn’t running continuously, it will reduce both our costs and the time we spend on the server side. Periodic tasks can also be included in this; instead of dealing with cron or Celery, we can hand that part off to the cloud provider. Repeating task pieces can be included here too — for example, sending email is a system that is used very frequently and integrated into almost every project over and over again. Instead, we can write an application for email sending and reduce our workload with a cloud provider that offers serverless services.

Conclusion

Serverless — also known as serverless computing or FaaS — is an approach that doesn’t eliminate servers but reduces the workload on us. Everything except the application code itself can be handed off to the cloud provider. It is a scalable, cost-reducing approach.