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Worker Bindings

Bindings allow your Workers to interact with resources on the Cloudflare Developer Platform.

There are multiple types of bindings available today:

D1: APIs available in Cloudflare Workers to interact with D1. D1 is Cloudflare’s native serverless database.
Durable Objects: A globally distributed coordination API with strongly consistent storage.
KV: Global, low-latency, key-value data storage.
mTLS: Configure your Worker to present a client certificate to services that enforce an mTLS connection.
Queues: Send and receive messages with guaranteed delivery.
R2: APIs available in Cloudflare Workers to read from and write to R2 buckets. R2 is S3-compatible, zero egress-fee, globally distributed object storage.
Service bindings: Facilitate Worker-to-Worker communication.
Vectorize: APIs available in Cloudflare Workers to interact with Vectorize. Vectorize is Cloudflare’s globally distributed vector database.
Version metadata: Exposes Worker version metadata (versionID and versionTag). These fields can be added to events emitted from the Worker to send to downstream observability systems.