Thanks for the report. I've been looking at the issue already. Adding a new arch requires a bit of work, because there's a circular build dependency so you have to build manually. And I don't have an arm64 to hand, so I'll have to use a porter machine. Will get around to it.
I doubt the i386 "out of memory" is from hitting the hard architectural limit, I think the default limits are just too low on i386. There are options that can be passed to increase the heap size, but the build system and documentation are sufficiently convoluted to make figuring out what they are and how to get them passed through isn't easy. If anyone who uses this in anger on an i386, or wants to use it on an arm64, would like to lend a hand, all assistance would be welcome! Meantime I'll probably just make it amd64-only for the next upload, with a wishlist bug to get other supported architectures working.
