I followed the advice from here
I changed the branch to 4.4.4 instead of the 4.4.0 listed there. The build was successful, though it took a few hours to complete on my 8GB Pi 4.
The hiccup I’m running into now is that the process won’t stay running. I can run mongod, and it’ll spit out a bunch of messages, then terminate. If I run as root, everything is fine, but I get a warning about running the process as root user. I also get a warning stating the rlimits are too low, current value 1024.
I don’t mind running as root for the time being, but will the rlimits warning become a problem later?