Function as a Service (FaaS)

Computers are relatively simple. You can use them to store data, move data, and perform operations on that data. People can now use services to manage their data centres, network security, and software applications. Functions as a Service (FaaS) are the software equivalent of a clothing store. Each function carries out a very specialized task.

We will cover the following:

  1. What is Function as a Service (FaaS)?
  2. How does FaaS Work?
  3. FaaS Use Cases
  4. Benefits of FaaS
  5. Challenges in FaaS
  6. Best Practices for FaaS

What is Function as a Service (FaaS)?

Let's start with a basic understanding of functions. A function specifies how to transform one element into another. The function remains constant, but the variables it passes through can change.

Function-as-a-Service (FaaS) is a form of cloud computing service that lets you run code in response to events without having to deal with the complicated infrastructure that comes with creating and launching microservices applications. The concept is built on serverless computing technologies and architectures, which enable software developers to quickly deploy cloud applications without having to manage servers.

Provisioning and managing a virtual or physical server, as well as an operating system and web server hosting operations, are often required when hosting a software application on the internet. Using FaaS, your cloud service provider automatically controls the actual hardware, virtual machine operating system, and web server software. This gives you the freedom to concentrate entirely on particular functions in your application code.

Instead of deploying and managing your own servers, Function as a Service (FaaS) allows you to acquire backend services from a vendor for your cloud applications. Your application is divided into "functions," which are pieces of it that are triggered by various events. The functions can then be uploaded to the vendor's FaaS platform and the event source attached.

Serverless vs. FaaS

Although serverless and FaaS are frequently confused, the truth is that FaaS is a subset of serverless. Serverless is focused on any service category where the configuration, management, and payment of servers are transparent to the end-user, such as compute, storage, database, messaging, API gateways, and so on.

FaaS, on the other hand, is centred on the event-driven computing model, in which application code, or containers, only run in response to events or requests, and is likely the most central technology in serverless architectures.

How does FaaS Work?

Since FaaS is a cloud service execution model, an organization interested in using it should first establish a partnership with a cloud service provider that promotes its FaaS capabilities.

Developers are not responsible for managing application servers under the FaaS delivery model. Instead, the service provider hosts them externally and allocates them dynamically based on the customer's demands. Software developers can use FaaS service providers to deploy functions, which are small chunks of code that can be run on demand.

The service provider starts a server, executes the function, and then shuts it down when the function is invoked. Serverless architecture, unlike other models in which developers execute the application on a dedicated server, is only active while the function is being utilized. The function can be shut down after it has completed its task, allowing the same computational resources to be devoted to other tasks.

Developers can use functions-as-a-service to access a platform that performs application logic on-demand while the service provider secures and coordinates all application resources. The FaaS design is best for simple, repetitive services like scheduling routine tasks or jobs, processing web requests, or processing queue data.

FaaS Use Cases

FaaS is ideal for high-volume, embarrassingly parallel workloads because it allows transactions to be separated and expanded quickly. Data processing, format conversion, encoding, and aggregation are also performed using FaaS.

  • Built-in Quality
    These cloud provider servers are advantageous in terms of availability, security, and maintenance-related duties; otherwise, human management is required.
  • Simplified Developer Logistics
    The development team appreciates the FaaS service since it streamlines application development and makes providing updates to users a breeze.
  • On-demand Functionality
    FaaS' ability to provide "on-demand" functionality is one of the most effective use cases. The "on-demand" functionality allows any infrastructure to be powered down, lowering costs and lowering bills.

Benefits of FaaS

Eliminating on-premises servers can save a software lot of costs, but the benefits of FaaS don't end there. Consider how FaaS might affect your business in the following areas:

  • Costs
    In most cases, you only pay for the services you really utilize. As opposed to suppliers who use a server allocation model, you don't have to pay in advance for a specified quantity of bandwidth.
  • Scalability
    FaaS platforms enable applications to scale automatically in response to the number of users or usage. Scaling is handled by the vendor, not the developer.
  • Simplified Code
    You can upload a single function at a time or your complete application at once with FaaS. In a similar way to microservices, FaaS allows you to develop backend code for independent functions.
  • Reduced Latency
    The FaaS provider might be able to run applications closer to end-users, reducing the requirement for requests to travel great distances to an origin server.
  • Faster Time to Market
    Iterative development is helped by FaaS, which allows you to get applications up and running faster and make changes more quickly.
  • Robust Cloud Infrastructure
    Since it is dispersed across many availability zones per geographic location and can be deployed across any number of regions without incurring additional expenditures, FaaS has intrinsic high availability.

Challenges in FaaS

Using Function as a Service could have some drawbacks. Before you go all-in with FaaS, there are a few things to think about:

  • Vendor Lock-in
    If you build your application on a FaaS platform, you can become to dependant on one vendor and find it difficult to leave.
  • Security
    When it comes to security, you're at the vendor's mercy, and you might not have the visibility you need to guarantee the vendor follows the rules controlling your usage or storage of certain types of data.
  • Testing Hurdles
    Creating a test environment for your application may be difficult depending on the vendor.
  • Cold Starts
    There are sometimes a few seconds delays in the execution of a function, which can be problematic for some applications.

Best Practices for FaaS

There are a few best practices you can follow to make FaaS deployment and use easier and more effective:

  • Use as Few Libraries
    Using too many libraries might cause functions to slow down and become difficult to scale.
  • Each Function Perform Only One Action
    FaaS functions should be built to complete a particular task in response to a specific event. Limit the scope of your code, make it efficient, and keep it small so that functions load and run rapidly.
  • Don't Make Functions Call Each Other
    The isolation of functions is what makes FaaS so valuable. Too many functions will increase your expenditures and detract from the value of function isolation.


If you want to migrate applications to the cloud quickly and cheaply, FaaS is a great platform to use. It all comes down to you and your work environment in the end. Determine whether the FaaS is appropriate for your environment. FaaS is similar to any other workflow that caters to a certain set of requirements and fits into specific conditions.

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Janani works for Atatus as a Content Writer. She's devoted to assisting customers in getting the most out of application performance monitoring (APM) tools.

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