Braintrust

Lightweight server monitoring with Docker stats and alerts

Beszel is a lightweight, self-hosted server monitoring platform built in Go that tracks CPU, memory, disk, network, GPU, temperature, and Docker container metrics with historical data visualization and configurable alerts. Its simple hub-and-agent architecture deploys in minutes and consumes minimal resources compared to traditional monitoring stacks like Prometheus and Grafana.

Open-source LLM gateway with built-in optimization and A/B testing

TensorZero is an open-source LLMOps platform in Rust that unifies an LLM gateway, observability, prompt optimization, and A/B experimentation in a single binary. It routes requests across providers with sub-millisecond P99 latency at 10K+ QPS while capturing structured data for continuous improvement. Supports dynamic in-context learning, fine-tuning workflows, and production feedback loops. Backed by $7.3M seed funding, 11K+ GitHub stars.

Open-source LLM engineering platform for observability

Langfuse is an open-source LLM engineering platform with 29K+ GitHub stars for tracing, evaluating, and monitoring AI applications. Acquired by ClickHouse, it provides detailed traces of LLM calls, prompt management with versioning, dataset-based evaluation, user feedback collection, and cost tracking. Framework-agnostic with native integrations for LangChain, LlamaIndex, OpenAI SDK, and Vercel AI SDK. Offers both self-hosted deployment and a managed cloud service.

LLM application observability and evaluation platform

LangSmith is LangChain's platform for debugging, testing, evaluating, and monitoring LLM applications in production. Provides detailed tracing of every step in LLM chains and agent workflows, dataset management for regression testing, prompt versioning, and automated evaluation with custom metrics. Features an annotation queue for human feedback, online monitoring dashboards, and integration with LangChain, LangGraph, and any LLM framework via the Python/JS SDK. Essential for production LLM ops.

Open-source platform for the complete machine learning lifecycle.

MLflow is an open-source platform for managing the end-to-end machine learning lifecycle. Covers experiment tracking, model packaging, model registry, and deployment. Created by Databricks and now a Linux Foundation project. Integrates with TensorFlow, PyTorch, scikit-learn, Hugging Face, and all major ML frameworks.

Open-source LLM observability through a single-line proxy

Helicone is an open-source LLM observability and AI gateway platform with proxy-based request logging, cost tracking, latency monitoring, caching, rate limits, user analytics, prompt tools, and HQL. It supports OpenAI, Anthropic, Azure, LiteLLM, Anyscale, Together AI, and OpenRouter integrations, and now presents itself as part of Mintlify while continuing managed and self-hosted gateway/observability workflows.