How to improve your VCL skills

Improving language skills to advance to the next level of knowledge can be a learning challenge that will certainly pay off when you can figure out how to intervene and fine-tune cache behavior in a granular way.

The difficult thing is to get started, then, as is well known: practice makes perfect.

To better understand the request lifecycle and how to take advantage of each phase, we offer this introductory post as a guide and encourage you to explore the official Varnish documentation.

VCL domain is a one-way path to achieving total optimization of your website, not only in terms of caching, but also in the intelligent handling of requests and responses.

Developing a project to build your own cache will give you the necessary basic skills and competencies that you can then apply in the CDN.

From caching to edge computing

While Varnish is commonly used as a caching system, one of the biggest draws of VCL is that it allows you to go beyond that and manage edge logic. Using subroutines, you can precisely control how data is manipulated on edge servers before being delivered to the client, offering unparalleled flexibility for optimizing web performance.

Use custom subroutines to keep your code clean

As you add more logic to your VCL setup, it’s easy for the code to become difficult to maintain. One of the best practices is to take advantage of custom subroutines with descriptive names. This not only makes the code easier to read, but it also helps to avoid duplication of logic.

For example, if you need to apply the same set of caching rules at multiple stages, creating a subroutine like sub cache_rules() and calling it from different points will allow you to centralize the logic and make it easier to modify in the future.

Tip-> whenever you add new functionality, ask yourself: is this something that could be reused? If the answer is yes, a subroutine is the right solution!

Practices you can do to perfect your skills

Constant practice is your best friend to advance your knowledge. That is why we propose some exercises that will allow you to apply the knowledge you acquire:

Create advanced caching rules: Try to implement caching policies that include various criteria, such as different expiration times depending on the type of content or user agent.
Fallback Handling: Configure your system to handle effective fallbacks in the event of errors on the origin server, delivering cached pages to avoid service interruptions.
Transform and manipulate responses: Modify responses from the origin server before they reach the client.
Dynamically redirect requests: Based on conditions such as geolocation or user agent, you can redirect requests to different servers or manipulate how resources are handled in real time.

By using custom subroutines, understanding the phases of request processing, and constant improvement through resources such as webinars and tutorials, you can evolve from simple caching at the edge to true edge logic.

How to apply what you learned on our platform

If you want to take your new VCL skills to the next level and maximize the use of the Transparent Edge platform, you can request support from one of our experts.

You will find predefined functions in our documentation, and you can practice implementing them in a use case. Our platform gives you the flexibility to adapt VCL to your specific needs.

On the other hand, if you have already mastered the creation of custom subroutines, and you have a certain degree of autonomy to manage your code, we will always be available to help you upload the custom functions you develop, ensuring that you have all the necessary tools to optimize your cache and improve web performance.

A constantly evolving platform

Our platform is constantly evolving, so if you need anything additional or are missing any functionality, our team will be happy to assist you in its implementation.

Developing and improving your VCL skills will not only allow you to take full advantage of the power of Varnish, but will also give you a competitive advantage by managing your edge applications accurately and efficiently.