How Edge Functions Can Improve The Performance Of Your Website

How Edge Functions Can Improve The Performance Of Your Website

As the world of web development continues to evolve, more tools and techniques are available to improve website performance.
One of the most powerful of these tools is edge functions and serverless computing. This technology is becoming increasingly popular among developers and businesses that want to provide their users with a faster, more responsive and custom web experience possible.

In this article, we are going to jump into the world of edge functions and explain what this technology is and its benefits and importance. With the knowledge of edge functions accomplished, we are introducing a list of edge function providers with their individual benefits and drawbacks. Finally, we will explore whether edge functions are always the optimal solution and discuss factors to consider when evaluating their suitability.

Table of contents

  1. What Are Edge Functions
  2. Benefits of Edge Functions
  3. The Importance of Edge Functions for Startups
  4. Edge Functions Providers
  5. Are Edge Functions always the optimal solution?

1. What Are Edge Functions

So, what exactly are edge functions? In simple terms, they are small snippets of code that are executed on-demand at the edge of the network. This means that the code is executed close to the user's device, rather than on a central server that may be located thousands of kilometers away. By running code on the edge, the response time is minimized, and website page speed is improved.

In traditional web development, a server is rented to handle requests that are located in a physical data center. This approach shows issues when incoming traffic is scattered all around the world: wherever this request is coming from, it will be processed and served from the server location, so the farthest from the main server location the longer it takes for this request to arrive at the main location to be processed.

CDNs (Content Delivery Networks) were designed to distribute, duplicate or cache static web content relative to end users through a geographically distributed network of proxy servers and their data centers. Edge computing is meant to do work in a similar way: the distribution it brings is for dynamic processing so the code you deployed is not located in a single server instance located in a centralized place but it is distributed and therefore, the processing happens in the edge closer to the end user. In fact, this allows a distribution of dynamic processing instead of just static files and media content.

One important consideration here is that not all processes can be accomplished with edge functions due to some technology limitations.
The limitations can vary depending on the provider. Some of these limitations are: restrictions on the package size of the code to be deployed, limit in the timeout of the executed code, usage of some features or apis of a certain runtime, usage of environment variables, etc.

2. Benefits of Edge Functions

One of the primary benefits of using edge functions is that they allow developers to optimize the way that their websites are delivered to users. The utilization of this technology allows customization of the content that is delivered to individual users based on their location, device type, or other relevant factors.
As mentioned before, this customization can include optimizing images or other content, compressing files, or even serving up completely different versions of a website for different users.

Another major benefit of edge functions is that they can be used to improve website security. By running code on the edge, developers can implement security measures that protect against various types of attacks, including DDoS attacks, cross-site scripting (XSS), and SQL injection attacks. This can be especially important for websites that handle sensitive user data or financial transactions.

Perhaps the most significant benefit of edge functions is that they can improve the overall performance of a website. By running code on the edge, response times are minimized, and website page speed is improved. This can lead to a much faster and more responsive web experience for users, which can be crucial for keeping them engaged and coming back to a website.

In addition to these benefits, edge functions are also highly scalable and can be easily integrated into existing website infrastructure. This makes them a powerful tool for businesses and developers who want to improve their website performance without having to completely overhaul their existing systems.

When speaking about development costs, using edge functions can lower server setup and management costs, as there's no need to provision or maintain any server. This allows the development team to concentrate on the business.

The Importance of Edge Functions for Startups

Now that we listed the benefits, you may ask yourself “Okay but how and in which way do these benefits affect my business?” Edge Functions can be helpful for any company, regardless of size or industry. However, when talking about small businesses and startups, Edge Function can give them an extra boost, because they often have limited resources and need to move quickly to gain traction. The following list helps you identify all critical and important key factors:

  1. Edge functions can improve performance: Edge functions can be used to execute code closer to the user's device, reducing latency and improving the performance of your application. By caching content, optimizing images, and performing other optimizations at the edge, you can deliver a faster and more responsive and customized user experience. However, you have to keep in mind edge functions are not the only tool to take into consideration when you want to improve your website performance.

  2. Server response time is critical: The response time of your server can have a significant impact on the user experience of your application. Slow server response times can result in longer load times, delayed content delivery, and a poor user experience. As a startup, it's important to invest in fast and scalable server infrastructure to ensure that your application can handle traffic spikes and provide a responsive experience to users.

  3. Choose a CDN provider carefully: When selecting a CDN provider, it's important to consider factors such as performance, reliability, and security. Look for a provider that has a global network of servers, high uptime, and strong security features. Some popular CDN providers for startups include Cloudflare, Akamai, and Amazon CloudFront. Another consideration is the integration with your current infrastructure. The ease of integration with your current system is another point to take into account.

  4. Test and optimize: As a startup, it's important to continuously test and optimize your application to ensure that it is providing a fast and responsive user experience. Use tools like Google Lighthouse or WebPageTest to measure your page load times and identify areas for optimization. Continuously monitor your server response times and use techniques like caching, compression, and code optimization to improve performance.

By keeping these factors in mind, edge functions can provide startups with a range of benefits that can help them overcome common challenges like limited resources, scalability, and security. By leveraging edge functions, startups can focus on developing their product and growing their business, without being hindered by infrastructure or performance issues.


Edge Function Providers

When it comes down to choosing which provider you should work with, there are several known edge function providers that offer a variety of features and capabilities for developers. Here are some of the most popular edge function providers with their benefits and drawbacks listed below:

1. Cloudflare Workers - Cloudflare Workers is a serverless platform that enables developers to build and deploy edge applications quickly and easily. With Workers, you can write JavaScript code that runs on Cloudflare's global network of servers, reducing latency and improving performance.


  • Easy to use and quick to deploy
  • Offers low-latency global edge network
  • Strong security features
  • Provides a free tier for testing and development


  • Limited runtime environment compared to other providers
  • Limited access to third-party integrations

2. AWS Lambda@Edge Function - AWS Lambda@Edge is a serverless computing service that enables developers to run code at the edge of the Amazon Web Services network. With Lambda@Edge, you can perform a variety of tasks, such as modifying HTTP requests and responses, caching content, and optimizing images


  • Offers high performance and low latency
  • Provides a wide range of integrations with other AWS services
  • Provides a wide range of runtimes, including Node.js and Python


  • Higher cost compared to other providers
  • Requires Amazon Web Services experience and knowledge to set up and configure

3. Microsoft Azure - Azure offers a range of edge computing services, including Azure Functions, which provides serverless computing at the edge, and Azure IoT Edge, which is designed for edge computing in IoT environments.


  • Scalable platform
  • Global network of data centers and edge locations
  • Integration with other Microsoft services and tools
  • High level of security and compliance


  • Complexity and learning curve
  • Potentially high cost
  • Limited documentation
  • Risk of vendor lock-in

4. IBM Cloud Functions - IBM Cloud Functions is a serverless computing service that allows you to create and run event-driven functions that respond to cloud events and execute in milliseconds.


  • Scalable, efficient, and cost-effective serverless architecture
  • Easy integration with other IBM Cloud services
  • Supports multiple programming languages and event-driven programming
  • Pay-per-use pricing model for low traffic applications


  • May experience cold start latency
  • Debugging serverless functions can be challenging
  • Limited control over the runtime environment and 10 minute function timeout

5. Fastly Compute@Edge - Fastly Compute@Edge is a serverless computing platform that enables developers to build and deploy edge applications using JavaScript or WebAssembly. With Compute@Edge, you can perform a variety of tasks, such as URL rewriting, content transformation, and caching.


  • Provides powerful real-time data processing capabilities
  • Offers a flexible and customizable deployment platform
  • Provides strong security features


  • Higher cost compared to other providers
  • Limited community support compared to other providers

6. Google Cloud - Google Cloud provides a suite of edge computing services, including Cloud Functions for deploying serverless applications and Anthos, a platform for managing applications across on-premises and multi-cloud environments.


  • Scalability and performance
  • Integration with other Google Cloud services and tools
  • Flexibility and customization options
  • Wide range of programming languages supported


  • Complexity and learning curve
  • Potentially high cost
  • Limited support for certain programming languages and frameworks
  • Security concerns due to centralization of data

7. Vercel Functions - Vercel is a cloud platform that provides serverless functions and allows developers to deploy them to handle dynamic requests and data processing at the edge.


  • Wide compatibility with modern frameworks
  • Simple deployment of websites and applications
  • Automatic scaling configuration
  • On-demand deployment without limitations


  • Lack of built-in crash-handling mechanisms
  • Insufficient automation of development workflows
  • Need for highly skilled developers to manage the tech stack

Are Edge Functions always the best solution?

While edge functions can be a powerful tool for improving the performance and reliability, while letting the development team to focus on the business rather than on technical underlying implementations of the hosting, they are not always the right solution for every situation. Here are some limitations that can make a serverless solution not suitable for your problem:

1. Limited functionality

While edge functions can perform a variety of tasks, they are not always suitable for complex or resource-intensive operations or long term running tasks. If your application requires a high level of processing power or complex calculations, it may be better to perform these operations on the server.

2. Limited control

Edge functions are executed on third-party servers, which can limit your control over the execution environment. This can make it difficult to debug issues or implement customizations.

3. Increased complexity

Adding edge functions to your application can increase complexity and introduce new points of failure. If you are not familiar with edge functions or serverless computing, it may be better to stick with more traditional approaches to application development.

4. Higher costs

While serverless computing can be cost-effective, the costs can add up quickly if you are not careful. Edge functions may not be the best choice for applications with limited budgets for high traffic volumes. It is in fact cheaper using edge functions than hosting and maintaining multiple servers across the globe until you reach a certain amount of requests.

5. Development approach

The development approach is different from the traditional server one. Working with sql databases with a long term pool of connections is not possible with serverless functions. While some workarounds can be done to still use traditional sql databases, a new approach with serverless databases is recommended. This does not apply only to technology choices but to the modeling of the application itself. A serverless paradigm can be challenging the first time working with it.


Wrapped up

Ultimately, the decision to use edge functions will depend on your specific application requirements and goals. If you are unsure whether edge functions are the right solution for your application, it may be helpful to consult with a qualified developer or IT professional.

Lastly, edge functions can be used in conjunction with traditional servers or serverless functions since they are meant to improve the performance and responsiveness of your application by handling these requests on the edge. Not just about performance, but they are also useful for modifying some response parameters like headers for application security.

On the other side, serverless functions are more a replacement for traditional server or a complement for new functionality where you can set up units of process in the cloud with minimum effort in terms of provisioning, maintenance and scaling.