A program that detects similar regions between samples in a multi-sample VCF file?

Question

[Joel Wallenius]

Greetings, stellae.

I was using the pixy software, hoping to find IBDs (regions of DNA that are identical between samples because they're (~closely) related). But, the pi statistic is not 0 if any site (within the (non-sliding) window) is heterozygous. Thus my plans are ruined. I know there are plenty of IBD softwares but they all seem kind of... backstreet.

Is there not a software in existence that detects long stretches of DNA where e.g. samples A, B, and C have the same (diploid, human) un-phased alleles, i.e. AA=AA, BB=BB, AB=BA, BA=AB?

Or must I write my own Python script for this? I can do it, but Python is single core...

Big thanks in advance! Joel