--- title: Event subscriptions description: Subscribe to Workers Builds events and send notifications to Slack, Discord, or webhook endpoints. image: https://developers.cloudflare.com/dev-products-preview.png --- > Documentation Index > Fetch the complete documentation index at: https://developers.cloudflare.com/workers/llms.txt > Use this file to discover all available pages before exploring further. [Skip to content](#%5Ftop) # Event subscriptions [Event subscriptions](https://developers.cloudflare.com/queues/event-subscriptions/) allow you to receive messages when events occur across your Cloudflare account. Cloudflare products (e.g., [KV](https://developers.cloudflare.com/kv/), [Workers AI](https://developers.cloudflare.com/workers-ai/), [Workers](https://developers.cloudflare.com/workers/)) can publish structured events to a [queue](https://developers.cloudflare.com/queues/), which you can then consume with Workers or [HTTP pull consumers](https://developers.cloudflare.com/queues/configuration/pull-consumers/) to build custom workflows, integrations, or logic. For more information on [Event Subscriptions](https://developers.cloudflare.com/queues/event-subscriptions/), refer to the [management guide](https://developers.cloudflare.com/queues/event-subscriptions/manage-event-subscriptions/). ## Send build notifications You can deploy a Worker that consumes build events and sends notifications to Slack, Discord, or any webhook endpoint: [![Deploy to Cloudflare](https://deploy.workers.cloudflare.com/button)](https://deploy.workers.cloudflare.com/?url=https://github.com/cloudflare/templates/tree/main/workers-builds-notifications-template) The template sends notifications for: * Successful builds with preview or live deployment URLs * Failed builds with error messages * Cancelled builds ![Example Slack notifications for Workers Builds events](https://developers.cloudflare.com/_astro/builds-notifications-slack.rcRiU95L_169ufw.webp) You can customize the Worker to format messages for your webhook provider. For setup instructions, refer to the [template README ↗](https://github.com/cloudflare/templates/tree/main/workers-builds-notifications-template#readme). ## Available Workers Builds events #### `build.started` Triggered when a build starts. **Example:** ``` { "type": "cf.workersBuilds.worker.build.started", "source": { "type": "workersBuilds.worker", "workerName": "my-worker" }, "payload": { "buildUuid": "build-12345678-90ab-cdef-1234-567890abcdef", "status": "running", "buildOutcome": null, "createdAt": "2025-05-01T02:48:57.132Z", "initializingAt": "2025-05-01T02:48:58.132Z", "runningAt": "2025-05-01T02:48:59.132Z", "stoppedAt": null, "buildTriggerMetadata": { "buildTriggerSource": "push_event", "branch": "main", "commitHash": "abc123def456", "commitMessage": "Fix bug in authentication", "author": "developer@example.com", "buildCommand": "npm run build", "deployCommand": "wrangler deploy", "rootDirectory": "/", "repoName": "my-worker-repo", "providerAccountName": "github-user", "providerType": "github" } }, "metadata": { "accountId": "f9f79265f388666de8122cfb508d7776", "eventSubscriptionId": "1830c4bb612e43c3af7f4cada31fbf3f", "eventSchemaVersion": 1, "eventTimestamp": "2025-05-01T02:48:57.132Z" }} ``` #### `build.failed` Triggered when a build fails. **Example:** ``` { "type": "cf.workersBuilds.worker.build.failed", "source": { "type": "workersBuilds.worker", "workerName": "my-worker" }, "payload": { "buildUuid": "build-12345678-90ab-cdef-1234-567890abcdef", "status": "failed", "buildOutcome": "failure", "createdAt": "2025-05-01T02:48:57.132Z", "initializingAt": "2025-05-01T02:48:58.132Z", "runningAt": "2025-05-01T02:48:59.132Z", "stoppedAt": "2025-05-01T02:50:00.132Z", "buildTriggerMetadata": { "buildTriggerSource": "push_event", "branch": "main", "commitHash": "abc123def456", "commitMessage": "Fix bug in authentication", "author": "developer@example.com", "buildCommand": "npm run build", "deployCommand": "wrangler deploy", "rootDirectory": "/", "repoName": "my-worker-repo", "providerAccountName": "github-user", "providerType": "github" } }, "metadata": { "accountId": "f9f79265f388666de8122cfb508d7776", "eventSubscriptionId": "1830c4bb612e43c3af7f4cada31fbf3f", "eventSchemaVersion": 1, "eventTimestamp": "2025-05-01T02:48:57.132Z" }} ``` #### `build.canceled` Triggered when a build is canceled. **Example:** ``` { "type": "cf.workersBuilds.worker.build.canceled", "source": { "type": "workersBuilds.worker", "workerName": "my-worker" }, "payload": { "buildUuid": "build-12345678-90ab-cdef-1234-567890abcdef", "status": "canceled", "buildOutcome": "canceled", "createdAt": "2025-05-01T02:48:57.132Z", "initializingAt": "2025-05-01T02:48:58.132Z", "runningAt": "2025-05-01T02:48:59.132Z", "stoppedAt": "2025-05-01T02:49:30.132Z", "buildTriggerMetadata": { "buildTriggerSource": "push_event", "branch": "main", "commitHash": "abc123def456", "commitMessage": "Fix bug in authentication", "author": "developer@example.com", "buildCommand": "npm run build", "deployCommand": "wrangler deploy", "rootDirectory": "/", "repoName": "my-worker-repo", "providerAccountName": "github-user", "providerType": "github" } }, "metadata": { "accountId": "f9f79265f388666de8122cfb508d7776", "eventSubscriptionId": "1830c4bb612e43c3af7f4cada31fbf3f", "eventSchemaVersion": 1, "eventTimestamp": "2025-05-01T02:48:57.132Z" }} ``` #### `build.succeeded` Triggered when a build succeeds. **Example:** ``` { "type": "cf.workersBuilds.worker.build.succeeded", "source": { "type": "workersBuilds.worker", "workerName": "my-worker" }, "payload": { "buildUuid": "build-12345678-90ab-cdef-1234-567890abcdef", "status": "success", "buildOutcome": "success", "createdAt": "2025-05-01T02:48:57.132Z", "initializingAt": "2025-05-01T02:48:58.132Z", "runningAt": "2025-05-01T02:48:59.132Z", "stoppedAt": "2025-05-01T02:50:15.132Z", "buildTriggerMetadata": { "buildTriggerSource": "push_event", "branch": "main", "commitHash": "abc123def456", "commitMessage": "Fix bug in authentication", "author": "developer@example.com", "buildCommand": "npm run build", "deployCommand": "wrangler deploy", "rootDirectory": "/", "repoName": "my-worker-repo", "providerAccountName": "github-user", "providerType": "github" } }, "metadata": { "accountId": "f9f79265f388666de8122cfb508d7776", "eventSubscriptionId": "1830c4bb612e43c3af7f4cada31fbf3f", "eventSchemaVersion": 1, "eventTimestamp": "2025-05-01T02:48:57.132Z" }} ``` ```json {"@context":"https://schema.org","@type":"TechArticle","@id":"https://developers.cloudflare.com/workers/ci-cd/builds/event-subscriptions/#page","headline":"Event subscriptions · Cloudflare Workers docs","description":"Subscribe to Workers Builds events and send notifications to Slack, Discord, or webhook 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