Introduction
Building an LLM application no longer requires wiring orchestration code by hand. A class of open-source platforms now exposes retrieval, agents, and workflows through visual canvases, web UIs, and plain-English prompts. These tools let developers prototype in minutes and self-host for data control.
This article reviews ten open-source projects across three jobs: building LLM apps, building RAG systems, and building AI agents. Each entry covers what the tool does, its core capabilities, who it suits, and its verified license and repository.

