Locust offers Python-based load testing for teams designing concurrent requests around real flows.
Python user tasks describe load scenarios.
When designing concurrent requests around real flows, keep request ratios close to real usage.
Artillery offers load and continuous performance testing for teams testing traffic spikes before release.
Gatling offers a performance testing and traffic simulation platform for teams observing latency under service pressure.
Apache JMeter offers a protocol and service load testing tool for teams comparing API behavior at different concurrency levels.