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This is the documentation for Performance Edge. If you'd like access, please reach out to your Optimizely account manager.

Why did you decide to build Performance Edge?

Website speed matters. Studies show that faster loading websites correlate with better conversion rates and less abandonment. We’ve been on a mission to make Optimizely run faster on your site. Performance Edge is the next step forward in our mission to make experiments run blazingly fast on your website.

Do I need to be a Cloudflare customer to use Performance Edge?

No. We used Cloudflare to power the decisioning for Performance Edge, but we’ve made it possible to integrate Performance Edge with a wide variety of CDNs including, but not limited to, Cloudflare.

Additionally, Performance Edge does not require using a CDN. It's designed as an API that can also be used with a serverless architecture or by communicating with your origin server. However, for the best performance, we recommend using a CDN as you will see overall site performance benefits, as well as performance benefits for experiments.

Can I use Performance Edge with a serverless system?

Performance Edge is compatible with a serverless worker like Cloudflare Workers or AWS Lambda.

Why does your recommended approach hit a first-party endpoint?

Our recommended implementation approach sends a request to your domain (e.g., atticandbutton.com/optimizelyjs123), then a route handler forwards that request to Optimizely. This extra hop seems unintuitive, but actually helps increase page performance and reduce implementation costs. Crossing domains is slow for a browser. When your visitor's browser makes a request from your domain, it gives Optimizely access to header and cookie information that Performance Edge needs for browser targeting, device-targeting, to ensure that a certain variation is delivered, and more -- and it's faster.

Is Performance Edge faster than a self-hosted and asynchronous Web implementation?

Yes. Performance Edge is faster because it has a smaller snippet and less code to download and execute.

Can I make a Performance Edge experiment and a Web experiment mutually exclusive?

No. Performance Edge uses a different project type from Optimizely Web. Mutually exclusive experiments are only supported within projects, so you can't make Edge and Web experiments mutually exclusive.

Can I use Performance Edge and Web at the same time?

No, you cannot run Performance Edge and Web on the same page at the same time. Performance Edge is an add-on for Optimizely Web that takes a completely different approach to implementation and enables you to run website experiments faster by moving key experiment decisions from the browser to the Edge (CDN layer).

We recommend using Performance Edge for the parts of your website that have the most demanding performance needs and Web for the parts of your site where you need the greatest flexibility to support your experimentation use cases.

I have a custom snippet. Can I use Performance Edge with it?

Custom snippets are a feature of Optimizely Web and not available in Performance Edge. They are designed to reduce the footprint of the Optimizely snippet by breaking it up into multiple snippets that have a many-to-many relationship across projects and experiments.

The Performance Edge microsnippet goes further than the custom snippet from a performance standpoint and contains only the necessary variation content for a specific user. Performance Edge helps helps solve some similar performance challenges as custom snippets in Web -- but is faster. Custom snippets are also used by some teams to manage permissions and governance.

Does Performance Edge work with Program Management?

Yes. You can use Program Management to manage Performance Edge experiment ideas and provide visibility across your Edge experiments.