I maintain a fleet of 15 "flent" servers across the globe, leveraging irtt, iperf, netperf, and a few other tools. I do not have the resources to publish them widely (flent.org's tools are by design, intended more for folk to quickly spin up a server and client for internal tests, because most of the results are very embarrassing for the ISPs and vendors). They are widely available for linux and osx, as part of their package repositories, with packages for openwrt as well. My favorite tests in that suite are the rrul, rrul_be, "squarewave" and tcp_nup tests, which are still the only few that sample tcp_info enough to get cwnd and rtt statistics directly from the streams. waveform's speedtest leverages cloudflare's cdn. The new speedtest.net apps test for the presence of "FQ" more than bufferbloat, but also come in command line versions.