Mold

Mold is a synchronous webhook bridge that connects two Clay tables, enabling seamless data enrichment workflows in a single request/response cycle. Table A sends data to Mold, which forwards it to Table B for enrichment. Table B enriches the data and returns it to Mold, which passes the result back to Table A — all in one synchronous call.

No queues, databases, or polling required. Mold is a lightweight Hono server with minimal dependencies, secured with bearer token authentication, request capacity limits, and cryptographically random callback URLs. Deploy with one click to Render or Railway, or self-host with Docker.

1. 1
   Deploy Mold to Render, Railway, or your own server using the one-click deploy buttons or Docker image.
2. 2
   Set the MOLD_API_KEY environment variable to secure your instance with bearer token authentication.
3. 3
   In Clay Table A, add an HTTP API column that sends data to your Mold endpoint with the enrichment payload.
4. 4
   In Clay Table B, configure a webhook source to receive the forwarded data, enrich it, and return results via an HTTP API column pointing back to the Mold callback URL.
5. 5
   Table A receives the enriched data synchronously in the original HTTP response — no polling, no external state.