> A new use case processed about the same amount of data as their existing pipelines, but it ran much slower.

Did I miss something? They didn't mention why the new use case was slower. I was expecting some callback to that new usecase in the article somewhere.

Always enjoy reading about performance debugging, thanks for writing this.

Edit: they didn't talk about profiling either. It was an enjoyable read of rust serialisation for non rusty people though.