## Cloudflare Workers
Cloudflare Workers provides a serverless execution environment that allows you to create new applications or augment existing ones without configuring or maintaining infrastructure.
### Advantages of Cloudflare Workers
**Automatic scaling** – Traffic is automatically routed and load balanced across servers.
**High-performance global network** – Your code is powered by Cloudflare's global network.
**No cold starts** – Cloudflare supports 0ms cold starts.
### Cloudflare Workers use cases
For example use cases of Cloudflare Workers, check out their [documentation with various examples](🔗).
### Restrictions and Limitations
Cloudflare Workers have different plan limits and restrictions based on your account. Please refer to the official Cloudflare [Limit documentation](🔗) for more information.
## Optimizely + Cloudflare Worker Template
### Caching with Cloudflare
This template uses Cloudflare cache API to provide performant caching for the [Optimizely Datafile](🔗).
### Identity Management
Out of the box, Optimizely's Full Stack SDKs require a user-provided identifier to be passed in at runtime to drive experiment and feature flag decisions. This example generates a unique id, stores it in a cookie and reuses it to make the decisions sticky. Alternatively, you can use an existing unique identifier available within your application and pass it in as the value for the `
For more information on how Optimizely Full Stack SDKs assign users to feature flags and experiments, see [the documentation on how bucketing works](🔗).
## How to use
You will need to have these prerequisites to use this template:
Install the [Wrangler CLI](🔗).
### Get started
Generate a project using the [template hosted on GitHub](🔗):
account_id` in `
wrangler.toml`. If you do not know the account ID, just do `
wrangler dev` and the CLI will prompt you with the account ID and the instructions to add it.
Install node nodules.
Update your Optimizely `
flagKey` and `
userId` in `
src/index.js`. Your SDK keys can be found in the Optimizely application under **Settings**.
Test and debug the worker locally:
Deploy the worker on Cloudflare:
Tail the logs for debugging when accessing worker deployed on Cloudflare (optional):
## Additional resources
[Cloudflare Workers documentation](🔗)
[Cloudflare Workers tutorials](🔗)
[Cloudflare Workers with Optimizely Template on GitHub](🔗)