Cloudflare Workers - Services

A service is like a project. It's where you define your Cloudflare Workers and the events you test them with, all in a file called serverless.yml.

To get started building your first Serverless Framework project, create a service.


In the beginning of an application created by a team with an Enterprise Cloudflare account, and for the lifespan of an application made by a team with a Non-Enterprise Cloudflare account, we recommend you use a single Service to define all of the Functions and Events for that project.

 serverless.yml  # Contains all functions and infrastructure resources

However, as your application grows as an Enterprise Cloudflare user, you can break it out into multiple services. A lot of people organize their services by workflows or data models, and group the functions related to those workflows and data models together in the service.

 serverless.yml # Contains 4 functions that do Users CRUD operations and the Users database
 serverless.yml # Contains 4 functions that do Posts CRUD operations and the Posts database
 serverless.yml # Contains 4 functions that do Comments CRUD operations and the Comments database

This makes sense since related functions usually use common infrastructure resources, and you want to keep those functions and resources together as a single unit of deployment, for better organization and separation of concerns.


To create a service, use the create command. You can also pass in a path to create a directory and auto-name your service:

# Create service with cloudflare-workers template in the folder ./my-service
serverless create --template cloudflare-workers --path my-service

Here are the available runtimes for Cloudflare Workers:

  • cloudflare-workers
  • cloudflare-workers-enterprise
  • cloudflare-workers-rust

Check out the create command docs for all the details and options.


You'll see the following files in your working directory:

  • serverless.yml
  • helloWorld.js


Each service configuration is managed in the serverless.yml file. The main responsibilities of this file are:

  • Declare a Serverless service
  • Define one or more functions in the service
  • Define the provider the service will be deployed to
  • Define any custom plugins to be used
  • Define events that trigger each function to execute (e.g. HTTP requests)
  • Allow events listed in the events section to automatically create the resources required for the serverless invoke command

You can see the name of the service, the provider configuration and the first function inside the functions definition. Any further service configuration will be done in this file.

# serverless.yml

  name: hello-world

  name: cloudflare

  - serverless-cloudflare-workers

    # What the script will be called on Cloudflare (this property value must match the function name one line above)
    name: helloWorld
    # The name of the script on your machine, omitting the .js file extension
    script: helloWorld
    # Events are only relevant to the `serverless invoke` command and don’t affect deployment in any way
      - http:
          method: GET
            someKey: someValue

  # Only Enterprise accounts would be allowed to add this second function and its corresponding route above
    name: foo
    script: bar
      - http:
          method: GET


The helloWorld.js file contains a barebones Cloudflare Worker that returns ‘hello world’.


When you deploy a Service, all of the Functions, and Events in your serverless.yml are translated into calls to Cloudflare to create your Cloudflare Worker(s).

To deploy a service, first cd into the relevant service directory:

cd my-service

Then use the deploy command:

serverless deploy

Check out the deployment guide to learn more about deployments and how they work. Or, check out the deploy command docs for all the details and options.


To easily remove your Service from Cloudflare’s data centers, you can use the remove command.

Run serverless remove to trigger the removal process.

Serverless will start the removal and informs you about it's process on the console. A success message is printed once the whole service is removed.

The removal process will only remove the service on your provider's infrastructure. The service directory will still remain on your local machine so you can still modify and (re)deploy it to another stage, region or provider later on.

Version Pinning

The Serverless framework is usually installed globally via npm install -g serverless. This way you have the Serverless CLI available for all your services.

Installing tools globally has the downside that the version can't be pinned inside package.json. This can lead to issues if you upgrade Serverless, but your colleagues or CI system don't. You can use a feature in your serverless.yml without worrying that your CI system will deploy with an old version of Serverless.

Pinning a Version

To configure version pinning define a frameworkVersion property in your serverless.yaml. Whenever you run a Serverless command from the CLI it checks if your current Serverless version is matching the frameworkVersion range. The CLI uses Semantic Versioning so you can pin it to an exact version or provide a range. In general we recommend to pin to an exact version to ensure everybody in your team has the exact same setup and no unexpected problems happen.


Exact Version

# serverless.yml

frameworkVersion: '2.1.0'

Version Range

# serverless.yml

frameworkVersion: ^2.1.0 # >=2.1.0 && <3.0.0

Installing Serverless in an existing service

If you already have a Serverless service, and would prefer to lock down the framework version using package.json, then you can install Serverless as follows:

# from within a service
npm install serverless --save-dev

Invoking Serverless locally

To execute the locally installed Serverless executable you have to reference the binary out of the node modules directory.


node ./node_modules/serverless/bin/serverless deploy
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