FastCGI like feature

Serverless/webhooks are fine, but they introduce an additional layer of complexity (networking with everything that comes with it for example).

A FastCGI like feature, allowing hasura actions/events to call a custom program/worker run locally by hasura could allow to bypass those problems while allowing to run custom business code.

It might sound a bit old school but old concepts are sometimes interesting to revisit :)

What do you think?

No files, tests, or entry points are named. Start by reviewing how Hasura actions and events currently invoke webhooks or serverless handlers, then determine whether a local FastCGI-like worker is in scope; done requires an agreed design and clearly defined behavior before implementation.

Written by the indexing model from the issue text.