As promised, full build logs available here: https://people.debian.org/~sanvila/build-logs/node-temp/
This time I tried 100 times and it failed 96 times, so it failed 96% of the time. BTW: My autobuilders have nothing to do with reproducible builds autobuilders. They use pbuilder, I use sbuild. They have multiple CPUs, I usually have a single CPU. But in either case, the fact that this happens in both sets of autobuilders makes this unlikely to be a local problem in my side. Thanks.