What is Serverless & How Does it Work?

Serverless architectures can help you build scalable, cost-effective applications faster. They remove the burden of operating your own servers and leave you with APIs that you can use to trigger events when a user performs an action in your application or when new data is available. Because serverless also takes care of capacity monitoring and load balancing, it allows you to focus on developing your app instead of building out infrastructure. However, serverless architecture presents its own set of challenges and considerations that are unique from other architectures. This guide will explain what serverless architecture is, why it’s beneficial, how it works, different types of serverless solutions, and the pros and cons of using this type of architecture in your next project.


Serverless architecture :

Serverless architecture is an approach to software design that allows developers to build and run services without having to manage the underlying infrastructure. Developers can write and deploy code, while a cloud provider provisions servers to run their applications, databases, and storage systems at any scale. In this article, we’ll cover how serverless architecture works, the benefits and drawbacks of using it, and some tools that can help you go serverless.

Fundamental Concepts in Serverless Architecture:

Although serverless architecture eliminates the need for server management, there’s still a steep learning curve, especially if you’re chaining multiple functions together to create complex workflows in an application. It can therefore be helpful to familiarize yourself with these fundamental serverless terms:

  • Invocation
    A single function execution.

  • Duration
    The time it takes for a serverless function to execute.

  • Cold Start
    The latency that occurs when a function is triggered for the first time or after a period of inactivity.

Concurrency Limit
The number of function instances that can run simultaneously in one region, as determineSelf-hosted services – Self-hosted services are those that you host and manage yourself. An example of this type of service is Google Cloud Functions, which is a fully managed and integrated service similar to AWS Lambda.

  • AWS Lambda, Microsoft Azure Functions, Google Cloud Functions and IBM OpenWhisk are well-known examples of serverless services offered by the cloud providers. A function will be throttled if it exceeds this limit.

  • Timeout
    The amount of time that a cloud provider allows a function to run before terminating it. Most providers set a default timeout and a maximum timeout.

Keep in mind that each cloud provider may use different terminology and set unique limits on serverless functions, but the list above defines the basic concepts.


How does the serverless architecture works:

Serverless architectures rely on a third-party service to execute your code. While many services like AWS Lambda and Google Cloud Functions provide services that let you execute your code, many others let you store and analyze data, send emails, etc. This is one of the biggest benefits of serverless architecture: you can use a single service to do many things. In the case of AWS Lambda, for example, your code will run in a container that is isolated from other containers. This means that a single function cannot essentially “infect” other functions with its state, which makes it easier to scale and maintain your application. AWS Lambda also scales automatically, so you don’t have to worry about overloading your system and manually scaling down.

Different types of serverless solutions:

There are many different types of serverless solutions, including both managed and unmanaged offerings. They often integrate with other services like databases, CRMs, messaging systems, and more to allow for greater scalability and flexibility. This can make serverless architecture even more attractive to businesses.

  • Managed services – Managed services are those that are hosted and managed by a third-party service. An example of this type of service is AWS Lambda, which lets you run code without having to worry about infrastructural concerns.

Pros and cons of using serverless architecture:

There has been a significant increase in serverless adoption in recent years, with nearly 40 percent of companies worldwide using it in some form. Small startups and global corporations alike are leveraging serverless architectures for the following reasons:

    • Cost: Cloud providers charge you on a per-invocation basis, so you’re not paying for unused servers or virtual machines.
    • Scalability: Function instances are automatically created or removed in response to traffic variations, within the boundaries of concurrency limits.
    • Productivity: Engineers who use serverless can simply deploy their code without having to manage any servers, which helps accelerate delivery cycles and rapidly scale company operations.
  • No downtime: Because you are not managing your own servers, you don’t have to worry about them crashing and causing your app to go down with them.
  • No or low maintenance As a developer, you don’t have to worry about patching your servers or ensuring that your apps are running smoothly.
  • Quick development You can develop your app quicker because you don’t have to worry about setting up your own servers and can focus instead on your code.

There are also some challenges associated with serverless architectures(Cons)

  • Data governance: Because you do not control the servers where your code is running, you do not have full control over how your data is governed. This can be especially true in un-managed solutions, as you have no control over the servers themselves.
  • Security: Because your code is running on someone else’s servers, you cannot fully secure it. While most managed services have some sort of security features built in, un-managed solutions do not.
  • Testing: Developers can run unit tests on function code, but integration tests, which evaluate how frontend and backend components interact, are difficult to perform in a serverless environment.

Serverless Architecture Use Cases: 

Serverless architecture is best used to perform short-lived tasks and manage workloads that experience infrequent or unpredictable traffic. The main use cases for serverless include:

  • Trigger-based tasks
    Any user activity that triggers an event or a series of events is a good candidate for serverless architecture. For instance, a user signing up on your website may trigger a database change, which may, in turn, trigger a welcome email. The backend work can be handled through a chain of serverless functions.
  • Building RESTful APIs
    You can leverage Amazon API Gateway with serverless functions to build RESTful APIs that scale with demand.
  • Asynchronous processing
    Serverless functions can handle behind-the-scenes application tasks, such as rendering product information or transcoding videos after upload, without interrupting the flow of the application or adding user-facing latency.
  • Security checks
    When you spin up a new container, a function can be invoked to scan the instance for misconfigurations or vulnerabilities. Functions can also be used as a more secure option for SSH verification and two-factor authentication.
  • Continuous Integration (CI) and Continuous Delivery (CD)
    Serverless architectures can automate many of the stages in your CI/CD pipelines. For example, code commits can trigger a function to create a build, and pull requests can trigger automated tests

Tools That Support Serverless Architecture:

The right tool is very important to implement a serverless structure of any project to perform well for users. Once you’ve built your serverless application, you will need to monitor its health and performance, Serverless functions typically travel through a complex web of microservices, and cold starts, misconfigurations, and other errors can occur at any node and cause ripple effects throughout your environment. To help you troubleshoot, it’s critical to have real-time visibility into how each function is performing, both on its own and in communication with other functions and infrastructure components.


Serverless computing has been around for a while, but it has grown in popularity over the last few years. It is a cost-effective and scalable solution for companies that have a lot of traffic and need to handle more requests at once. The serverless architecture is also perfect for companies with unpredictable traffic patterns, as they don’t need to spend money on expensive servers when they don’t have any traffic at all.

With some incredible advantages, it’s no wonder that serverless architecture is predicted to rise in popularity in the coming years. However, just like any other architectural choice, it comes with its own set of tradeoffs and considerations. As a DevOps professional, it is essential to know and understand what is serverless and how it works. You might get hired to work on serverless concepts in your current and future company, and having a thorough knowledge of it can help you get the job easily.