BentoML is a machine-learning model serving framework and deployment platform. In production it lets developers define inference services via a decorator-based SDK (`@bentoml.service`, `@bentoml.api`), package those services into versioned "Bentos" with locked Python dependencies, and build OCI container images or deploy to Kubernetes, EC2, or BentoCloud. The serving layer supports both HTTP (Starlette/Uvicorn) and gRPC, with adaptive batching, model runners, Prometheus metrics, OpenTelemetry tracing, and pluggable monitoring. A comprehensive CLI (`bentoml serve/build/containerize/deploy`) is the primary operational surface, while the `_bentoml_sdk` and `_bentoml_impl` packages provide the user-facing and internal implementation layers respectively. Architecturally, the project separates concern into model registry, service definition, packaging, server workers, and cloud clients. Model artifacts are persisted in a versioned local store via framework adapters for PyTorch, TensorFlow, Transformers, ONNX, scikit-learn, MLflow, XGBoost, LightGBM, and others. Data flows from trained model artifacts into the registry, get referenced by service code, get bundled by `bentoml build` into self-contained Bento packages, and are served by Circus-managed worker processes. The core request path involves serialization, batching, resource allocation, and process supervision, all implemented in internal modules with generally clean abstractions. The repository is mid-migration from a legacy `bentoml.legacy.Service` API to a newer `_bentoml_sdk`, which creates visible duplication: two HTTP client stacks, multiple protobuf versions, and deprecation shims. This is a real maintenance cost but not a functional blocker; the modern SDK is actively developed, documented, and tested. The repo is clearly an application/framework rather than a data-research project; research-like artifacts are limited to test fixtures, training examples, and ML framework integration tests.