Ah the Waveform test is ours! I've been meaning to post it properly to HN since we launched it.

It's far from being a perfect bufferbloat/latency under load test, and there's lots of room to improve it, but we built it when DSL Reports seemed to be running a little unreliably.

We actually use Cloudflare and Fastly on the backend for latency/speed testing. We built and host the test for free mostly because I wanted it, but I justified the dev time as it being very-roundabout marketing for us - so if you ever need a signal booster or MIMO antenna for 5G internet, looks us up :).