Hi, @mbwatson. To me this looks a lot like a build that isn’t returning control to the build system because of some process that is still running in the background.
We have a support guide about this type of issue here:
The fact it is happening after the Algolia queries also strengthens the hypothesis that this is related to a subprocess or unclosed network connection of some kind.
Regarding finding memory issues, Gatsby is a node app so looking for node memory profiling techniques would be a good place to start.
That being said, personally, I think this looks like the Angolia subprocess doesn’t return (or close the connection handler) and not a memory issue. If it were me, I would start by looking for a connection close issue first.