Blockworkr
I volunteer my tech services for a few small non-profit orgs, provide hosting, maintain their firewalls, networks, etc. I've also given a few piholes to non tech family members... I found myself needing to keep DNS block lists (and more importantly, whitelists) synced between different sites. In a couple cases, I need to have different lists of lists on one or two of them. Two of these sites are rather remote rural installs with crap connections, my only remote access is via a reverse SSH connection out to one of my servers. I settled on creating a web service that I could centrally manage two or three different combinations of lists and provide each configuration as a single url to each pihole or firewall.
I mention this in the readme I made for this project, but I don't want to be a block list maintainer. I do maintain a white list, on another repo largely because some of the lists I use are anti-Microsoft. I also wrote a script to generate a very short (lightweight) block list based on actual network use on two of the networks I maintain (one hosts free public wifi). To be absolutely clear, I'm not looking to create the newest bestest most amzingest list to rule them all. My goal, is to give those of us who maintain more than one device that uses dns block lists a service we can host ourselves to centrally process and host your blocklist.
You can spin it up in docker, only needs one config file, see repo for more info. The project is very young, there are a lot of optimizations I can make and features I want to add, but at the end of the day, it's use case is fairly limited and it does most of that already. I'm actively using it on all the devices I manage.