Ask HN: Which extensible CMS would be good for a development team intranet

I'm trying to find a suitable tool that is both extensible and functions as a CMS, where I don't have to do a lot of work for the UI.

Integration with other systems via API calls, as an extensibility point would be a really nice feature.

I've tried many different CMS's and tools: Retool, Airplane, AdminJS.

But they seem to capture more the administrator part, than the "customizable overview" that I would like to focus on.

Does anyone have suggestions for platforms I could use to be able to extend the platform with, say, calls to Github to get a list of open pull requests, extract information about the recently applications deployed, etc.