# Vercel Daemons can now call services with bindings By Steven Van · 2026-10-30 Daemons declare a binding that names a service and an env variable, then call the private service's URL with a plain HTTP request. Vercel Daemons can now call the services in their deployment through [service bindings](), without those services being exposed to public traffic. The change applies to [Vercel]() daemons, the long-running background workers that run next to an app. ## Declaring a binding The binding is declared on the daemon, in either vercel.json or vercel.toml. It names the target service and the environment variable that receives the service's URL. In the example, a worker daemon binds the api service with type service, format url and env API\_URL. ## Calling the service Each instance receives the service's URL in that environment variable and calls it like any other HTTP endpoint, for example with a plain fetch to new URL('jobs/next', process.env.API\_URL). Vercel handles the internal routing, authentication and TLS, and the service stays private. ## Limits and deployment behaviour - Bindings point one way: services can't bind to daemons. - Bindings always point to the deployment that started the instance. After a promotion or rollback, instances from the previous deployment keep calling that deployment's services until they stop. Daemons are in beta. During the beta they run in production deployments with manually configured instance counts, and vercel dev does not currently run them. ![Vercel]() Vercel The platform for frontend developers — deploy, preview, and scale web apps and AI agents with zero config. [View Vercel →]() Sources [Original source]() [Read Vercel Daemons can now call services with bindings on Creators Toolbox]() --- Canonical source: https://creatorstoolbox.com/blog/vercel-vercel-daemons-can-now-call-services-with-bindings