Respan
LLM tracing, evals, and gateway
The top alternatives to MLflow in the Observability, Prompts & Evals space, compared on features, pricing, and what they're best at.
Updated March 27, 2026
MLflow is the leading open-source platform for managing the end-to-end machine learning lifecycle, now expanded into a comprehensive GenAI engineering platform. Created by Matei Zaharia (also the creator of Apache Spark) at Databricks in 2018 and donated to the Linux Foundation in 2020, MLflow has grown to over 20,000 GitHub stars and 60 million monthly downloads, making it one of the most widely adopted ML tools in the world.
One platform for routing, observability, tracing, and evals across every LLM provider.
Respan lets you trace LLM and agent calls across any model or framework, A/B test prompts on production traffic, and route requests across 500+ models through one gateway.