SGLang (short for Structured Generation Language) is an open-source framework for programming and serving large language models and multimodal models. It was introduced by researchers affiliated with LMSYS and other institutions as a system combining a Python-embedded language for structured generation with a runtime for high-throughput inference. The project is designed for low latency and high-throughput inference workloads, and its documentation describes support for features such as structured outputs, speculative decoding, continuous batching, quantization, and compatibility with OpenAI-style APIs.
History SGLang was publicly introduced in January 2024 by researchers affiliated with Stanford, UC Berkeley, Texas A&M, and Shanghai Jiao Tong University. Its academic description later appeared in the proceedings of NeurIPS 2024. In January 2026, TechCrunch reported that contributors associated with the project had formed the startup RadixArk to commercialize services around SGLang while continuing its open-source development.
Architecture According to the NeurIPS paper, SGLang consists of two main components: a front-end language embedded in Python and a back-end runtime for executing language model programs efficiently. The front end provides primitives for generation, selection, and parallel control flow, while the runtime uses a set of optimizations intended to reduce repeated computation and improve throughput. Among the techniques described by the project are RadixAttention for reusing key–value cache state across multiple generation calls, compressed finite-state machines for faster constrained decoding, and speculative execution for API-based models. The current documentation also describes support for serving both language models and multimodal models across a range of hardware back ends.
See also
Lists of open-source artificial intelligence software List of software developed at universities llama.cpp OpenVINO Open Neural Network Exchange TensorRT-LLM vLLM Comparison of deep learning software Comparison of machine learning software
References
External links SGLang overview at NVIDIA Docs SGLang documentation source repository on GitHub

