Self-Hosted Serving Selection — llama.cpp, Ollama, TGI, vLLM, SGLang

Four engines dominate self-hosted inference in 2026. Pick based on hardware, scale, and ecosystem. **llama.cpp** is fastest on CPU — widest model support, full control over quantization and threading. **Ollama** is the dev-laptop one-command install, ~15-30% slower than llama.cpp (Go + CGo + HTTP serialization), 3x throughput gap under prod-like load. **TGI entered maintenance mode December 11, 2025** — only bug fixes, ~10% slower raw throughput than vLLM but historically top observability and HF-ecosystem integration. That maintenance status makes it a risky long-term bet — SGLang or vLLM are safer defaults for new projects. **vLLM** is the general-purpose production default — v0.15.1 (February 2026) adds PyTorch 2.10, RTX Blackwell SM120, H200 optimization. **SGLang** is the agentic multi-turn / prefix-heavy specialist — 400,000+ GPUs in production (xAI, LinkedIn, Cursor, Oracle, GCP, Azure, AWS). Hardware constraints: CPU-only → llama.cpp only. AMD / non-NVIDIA → vLLM only (TRT-LLM is NVIDIA-locked). 2026 pipeline pattern: dev = Ollama, staging = llama.cpp, prod = vLLM or SGLang. Same GGUF/HF weights throughout.

Prerequisites: All Phase 17 lessons covering engines (04, 06, 07, 09, 18)