Bindings

Bindings allow your Workers to interact with resources on the Cloudflare developer platform.

There are multiple types of bindings available today.

​​ Configuration

Bindings can be configured by one of two ways:

• Updating your project’s wrangler.toml file.
• Logging in to the Cloudflare dashboard Open external link > Account Home > Workers & Pages > your Worker > Settings> Variables.

​​ Service bindings

Service bindings allow for communication with another Worker.

• Configure and learn more about Service bindings.

​​ KV namespace bindings

KV namespace bindings allow for communication between a Worker and a KV namespace.

• Learn more about KV namespace bindings.
• Configure KV namespace bindings via your wrangler.toml file.

​​ Durable Object bindings

Durable Object bindings for communication between a Worker and a Durable Object.

• Learn more about Durable Object bindings.
• Configure Durable Object bindings via your wrangler.toml file.

​​ R2 bucket bindings

R2 bucket bindings for communication between a Worker and an R2 bucket.

• Learn more about R2 bucket bindings.
• Configure R2 bucket bindings via your wrangler.toml file.

​​ Queue bindings

Queue bindings allow for communication between a Worker and a Queue.

• Configure Queue bindings via your wrangler.toml file.

​​ D1 database bindings

D1 bindings allow you to query a D1 database from your Worker.

• Configure a D1 binding.
• Learn more about how to query a D1 database using the client API.

​​ Dispatch namespace bindings (Workers for Platforms)

Dispatch namespace bindings allow for communication between a dynamic dispatch Worker and a dispatch namespace. Dispatch namespace bindings are used in Workers for Platforms. Workers for Platforms helps you deploy serverless functions programmatically on behalf of your customers.

• Configure dispatch namespace bindings via your wrangler.toml file.

​​ mTLS certificate bindings

mTLS certificate bindings enable Worker subrequests to present a client certificate when communicating with a service that requires client authentication.

• Learn more about mTLS certificate bindings.
• Configure mTLS certificate bindings via your wrangler.toml file.

​​ Email bindings

Email bindings allow you to send emails from your Worker. This is useful for when you want to know about certain types of events being triggered, for example.

• Learn more about email bindings.
• Configure email bindings via your wrangler.toml file.

​​ Constellation bindings

Constellation bindings allow for communication between a Worker and a Constellation project.

• Learn more about Constellation bindings.
• Configure Constellation bindings via your wrangler.toml file.