I have used Locust heavily in the past few month for loadtesting various apps and APIs. I've tried a couple different alternatives before settling with it, including ab and Vegeta.<p>Having the power of Python for scripting my loadtest was probably what sealed the deal for me. It allowed me to create a very powerful/reusable loadtesting framework that I can easily adapt very quickly to any app. Python scripting also allowed me to add features not build in to Locust's core itself like additional logging or metrics reporting and reading API endpoints from file/Redis/...<p>Also, being able to completely test all endpoints of an app at once is really useful. Most of the time, what I really want to know is can the whole backend handle the full traffic I'm expecting. Having clustering built-in helped a lot here. I was able to scale the loadtest to several thousands of RPS by just adding a couple more slaves...<p>The only feature I would like to see added is built-in Vegeta style graphs of latency/RPS over time. By default, Locust only gives you real time stat of the last second during the load test and a final average results in csv files. Combining metrics reporting with a graphing engine like Graphite can fix that though.<p>I highly recommend.