celld is an open-source daemon written in Rust that enables self-hosted, distributed execution of Cloudflare Workers and Durable Objects on your own infrastructure. The project provides an alternative to cloud-hosted Workers by allowing organizations to run the same workloads on their own machines while maintaining the distributed, durable characteristics of the original platform.
The architecture of celld centers on a novel approach to distributed state management. Each Durable Object is implemented as its own SQLite database, addressed by name and continuously replicated to an S3-compatible storage bucket that you control. Nodes in the fleet coordinate exclusively through this shared bucket using object-storage compare-and-swap operations, eliminating the need for a control plane, consensus service, or membership protocol. This design ensures that exactly one node owns a cell at any given time. The bucket serves as the durable source of truth, making individual nodes replaceable and allowing cells to migrate or wake up on different nodes by restoring their SQLite state.
The runtime embeds V8 and executes Wrangler bundles, the standard packaging format for Cloudflare Workers. Applications automatically shard by construction since each object is its own database, which eliminates contention and blast-radius failures that would occur with a shared database architecture. Idle cells hibernate to minimal resource consumption, and the system includes pressure-shedding capabilities to manage resource constraints on loaded nodes.
Deployment and operation are straightforward. The celld binary can be installed via a provided installer with verifiable provenance through GitHub attestations, or run as a container image available for Linux x86-64 and ARM64. The system uses the standard AWS credential chain and works with any S3-compatible storage service. Deployment happens through the celld deploy command, which invokes esbuild for Worker code and accepts the supported Wrangler configuration subset. Fleet discovery and peer coordination happen automatically through bucket leases with no separate account or join service required.
The project includes operational tooling such as celld diagnose, which enumerates node leases and performs signed direct probes of live peers, reporting on resident cells, WebSocket connections, memory usage, CPU utilization, and other metrics. Pressure shedding is configurable through resident-cell watermarks and optional process-level triggers on Linux.
Since its previous check on August 7, 2026, the repository has grown from 2043 to 2067 stargazers and from 53 to 54 forks, with open issues increasing from 13 to 14. The project maintains a rapid response latency on tracked issues, with a median response time of 0.1 hours. The most active tracked contributor is bacloud22. The codebase overlaps with contributors from microsoft/vscode, microsoft/typescript, and google-ai-edge/LiteRT-LM, indicating cross-pollination with significant open-source projects.
The project explicitly disables pull requests to maintain code quality and respect maintainer time, instead requesting thoughtful contributions be submitted as git format-patch attachments. The runtime and compatibility surface are documented as still evolving, with public tests covering standalone engine functionality and conformance testing against Workers and Durable Objects reference behavior, plus deterministic simulation of the distributed protocol under fault injection before each release.
