Add Cloudflare Workers world implementation

[ataylorme]

Summary

This PR introduces a complete Cloudflare Workers world implementation for the Workflow DevKit, enabling workflow execution on Cloudflare's serverless platform using Durable Objects for state management, D1 for cross-run queries, and Cloudflare Queues for message dispatch.

Key Changes

• WorkflowRunDO (Durable Object): A comprehensive per-run state machine that handles:

  • Event processing and validation with full state transition logic
  • Run, step, hook, and wait entity management
  • Stream chunk storage and retrieval for large data handling
  • Legacy spec version compatibility
  • Idempotent event handling and terminal state enforcement

• Storage Layer: Implements the Storage interface with:

  • Run listing via D1 index with fallback to Durable Objects for full data
  • Event creation and retrieval routed through per-run DOs
  • Hook and step management with cross-run query support via D1

• Queue Integration:

  • Message envelope format for Cloudflare Queues
  • Queue handler registration and batch processing
  • Integration with local world executor for handler execution

• D1 Index Schema: Lightweight global index tables for:

  • Workflow runs (with filtering by name/status)
  • Workflow hooks (with token-based lookup)
  • Automatic index updates on run mutations

• Streaming Support: Stream chunk storage in Durable Object storage with:

  • Multi-chunk write operations
  • Stream closure and metadata tracking
  • Byte-range read support

• Configuration & Utilities:

  • Type-safe config interface for Cloudflare bindings
  • Durable Object stub management and fetch helpers
  • ISO date serialization utilities

Notable Implementation Details

• Event processing logic ported from world-postgres with full validation including version compatibility checks, terminal state enforcement, and idempotent operations
• Hybrid storage model: DO storage for per-run data, D1 for global queries with intelligent fallback
• Monotonic ULID generation for deterministic ordering
• Comprehensive error handling with proper HTTP status codes (404, 409, 410, 425)
• Data filtering support (resolveData parameter) to exclude input/output when not needed

https://claude.ai/code/session_019jYBQA1pNTDjK4LGt8qFKA

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🦋 Changeset detected

Latest commit: f2ebe0e

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@workflow/world-cloudflare	Patch

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Review the following changes in direct dependencies. Learn more about Socket for GitHub.

Diff	Package	Supply Chain Security	Vulnerability	Quality	Maintenance	License
	npm/​@​cloudflare/​workers-types@​4.20250312.0

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[VaguelySerious]

Hi @ataylorme

We love seeing World contributions. The approach we're taking with community Worlds is that we'd like them to be published as third-party Worlds, which we then add/advertise on our list of Worlds. In order to get on this list, all you need is:

• Publish your World as an npm package
• Make a PR to our docs and the world-manifest.json file in this repo adding yourself

Once that's done, we'll verify whether the package works, is deployable/redeployable, and passes at least basic workflow e2e tests. If that looks good, we'll merge the PR! If your package gets significant community attention, we may consider moving to first-party support inside the workflow repository.