Library features:

• User defined dependencies checks with flexible settings.
• Dependencies checks functions are executed asynchronously.
• Built-in Plug module providing customizable response for a http health-check endpoint.
• Support for multiple independent Existence instances and associated health-checks endpoints (example use case: separate Kubernetes readiness and liveness http probes).
• Checks states are stored and accessed using a dedicated ETS tables per Existence instance, which means practically unlimited requests per second processing capacity.

https://github.com/Recruitee/existence