XML is one of those areas of the web foundations that APIs build on that I find myself coming back to again and again. It seems straightforward on the surface, but the details matter more than most people realize.
I have watched teams get this wrong in ways that cost them time, trust, and sometimes consumers. Getting xml right means understanding not just the technical side, but the business reasons behind why it matters and who is affected when it is done poorly.
This is the kind of building block that separates teams who are just shipping APIs from teams who are actually operating them. It is not glamorous work, but it is the work that keeps everything moving in the right direction across the API landscape.