Concepts: how Defer works

Ensure to be fluent with Defer’s Concepts before proceeding with this page.

Local Development

The good news is that Defer works locally by default; without a specific command.


Locally, background functions run in the background leveraging the Promise API, providing a behavior similar to production environments, with some limitations.

Development Limitations

Defer relies on the Promise API to execute background functions locally; it means that all executions are bound to the parent process and will be canceled if the parent process (ex: local server) crashed or is stopped.

Given this limitation, the following @defer/client APIs are supported locally:

  • delay(): will result in executing the function immediately
  • defer.cron(): CRONs do not get scheduled locally