The sourceforge link might indicate otherwise, but this is actively developed: https://github.com/rocky/remake. (I’m curious what sourceforge offers these days – are they rehabilitated from that malware affair?
Regarding remake itself, I wonder if there are plans to upstream some of these changes, and/or whether there’s any history of attempting to work with the GNU make maintainers.
BTW I chatted with the author Rocky up on the Oil zulip and took some notes on debuggers in dynamic languages:
He also wrote the bash debugger, so I hope to incorporate that knowledge into Oil. I mostly debug shell as a REPL, but there are use cases for a debugger.
For those who are still on the fence, remake is GNU make with extra stuff added. That means, your make files will work as is, including extra bells and whistles, and really, once your run remake -X you will not go back to plain gnu make.