Architecture: the entry-point boundary

@liminis/diagrams has four subpath exports. Which one(s) you install determines whether React ends up in your dependency tree at all.

Import	Needs React installed?	What it gives you
@liminis/diagrams	no	re-export of ./core
@liminis/diagrams/core	no	parseC4, validateC4, layoutC4Diagram, and all types
@liminis/diagrams/react	yes	C4Renderer, C4InteractiveRenderer, useC4DiagramDrag
@liminis/diagrams/server	yes	renderC4DiagramToSVG — source to SVG in one call

Does installing this package require React?

No. react and react-dom are optional peer dependencies. npm install @liminis/diagrams (or the pnpm/yarn equivalent) pulls in @dagrejs/dagre and nothing else. ./core has @dagrejs/dagre as its only runtime dependency — no React, no DOM globals, no document/window anywhere on that path. That’s what makes it usable from a CLI, a CI job, or a worker thread with nothing else on disk.

If you only need to parse C4-PlantUML source and lay it out — not render it to anything — install the base package and import from ./core. You are done; there is no React to add.

The cost of optional peers: importing ./react or ./server without react/react-dom installed fails at runtime, not at install time. If you’re building a headless tool and want to be certain nothing accidentally imports ./react, don’t add the peers.

Why isn’t ./server part of ./core?

./server (renderC4DiagramToSVG) is DOM-free — it never touches document or window, so it runs fine in Node, an Electron main process, or CI. But it is not React-free: it drives the presentational C4Renderer component through React’s renderToStaticMarkup (via react-dom/server) to produce the SVG string. “DOM-free” and “React-free” are different properties, and ./server only has the first one.

Because it needs react/react-dom at runtime, bundling it into ./core would make ./core’s “dagre and nothing else” guarantee false. Keeping it in a separate entry point means a consumer who only wants ./core never pays for React, even transitively.

(There’s a deferred idea — not built — of a React-free SVG serializer that walks LayoutResult directly and would let ./core own the whole parse→SVG path with dagre as its only dependency. It doesn’t exist today.)

The three-layer stack

Rendered by this package, from C4-PlantUML source — the same path any consumer takes. Drag a box if the automatic layout puts something awkwardly, or expand it for room.

./react is presentational plus interaction (drag), and knows nothing about Lexical, editors, or persistence — see the Limitations section for what that implies. ./server is a thin wrapper that chains ./core’s parse and layout with ./react’s presentational renderer through react-dom/server, so a headless caller gets one function instead of three.

Picking an entry point

• Headless CLI/CI tool that only needs the parsed diagram or a layout result (no image output) → ./core. No React anywhere.
• Headless CLI/CI tool that needs an SVG file → ./server. Needs react + react-dom installed, but nothing DOM-related.
• Interactive UI, embedding the renderer in your own app, with or without drag → ./react. Needs react + react-dom, and a DOM (browser or jsdom/happy-dom).

See Recipes for complete, runnable examples of the first two.