MLflow is an open-source ML lifecycle platform that provides experiment tracking, model registry, model deployment, evaluation, and observability for both classical ML and GenAI/LLM workflows. In production, it operates as a modular monolith: a Python backend (Flask/FastAPI) with SQLAlchemy-backed storage (SQLite, PostgreSQL, MySQL, MSSQL), a React/TypeScript web UI, and client SDKs for Python, R, Java, and TypeScript. The system exposes a REST API and CLI for logging experiments, registering models, collecting traces via OpenTelemetry, and managing an AI Gateway that routes requests to dozens of LLM providers with budget controls, guardrails, and traffic splitting. The architecture includes a plugin system for custom store backends, deployment targets, and authentication providers, as well as a custom linting tool (clint) and extensive CI/CD pipelines. Key entry points are the `mlflow` CLI, `MlflowClient` Python API, tracking server (`mlflow server`), gateway server (`mlflow gateway`), and model scoring server (`mlflow models serve`). Data flows from user instrumentation through asynchronous logging to the backend store, with traces and evaluations queryable via the UI or API. External dependencies span ML frameworks (scikit-learn, PyTorch, TensorFlow, LangChain, etc.), LLM provider SDKs, and infrastructure tools (Docker, Kubernetes, Helm).
TraceAI is a multi-language (Python, TypeScript, Java, C#) OpenTelemetry-based instrumentation SDK for AI/LLM applications. It provides drop-in auto-instrumentation for 50+ LLM providers, agent frameworks (LangChain, LlamaIndex, CrewAI, AutoGen, etc.), and vector databases (Pinecone, ChromaDB, Qdrant, etc.). The core library wraps SDK calls to capture structured spans with semantic attributes (tokens, model, messages, tool calls) and exports them via OTLP to any OpenTelemetry-compatible backend, with a default hosted backend at Future AGI. The architecture is a monorepo with per-framework packages that follow a consistent instrumentor pattern: register a tracer provider, instrument the target library, then make API calls. Key entry points are `register()` (Python/TypeScript), `TraceAI.init()` (Java), and `TraceAI.Register()` (C#). The SDK also includes context attribute propagation, PII redaction, evaluation tags, and configurable masking. While the codebase is well-structured and actively maintained, there is significant duplication across framework instrumentors and some tests rely on heavy mocking, which limits reusability of individual components.