@lostgradient/editor

@lostgradient/editor is Cinder's Svelte 5 markdown editing, review, and diffing surface — MarkdownEditor (Milkdown/ProseMirror-based rich editing), ReviewEditor (threaded comments, front matter, export), and DiffViewer (word-level Markdown diffing) — packaged separately so applications that only render buttons and tables do not install milkdown, prosemirror, or their own copy of @lostgradient/markdown.

Install

Install the package and its peer dependencies together:

bun add @lostgradient/cinder @lostgradient/editor @lostgradient/markdown @milkdown/ctx @milkdown/kit @milkdown/prose prosemirror-inputrules prosemirror-model prosemirror-state prosemirror-view svelte

The supported Svelte peer range is >=5.56.0 <6; this package is developed against Svelte 5.56.0. @lostgradient/cinder, @lostgradient/markdown, svelte, and the milkdown/prosemirror packages are all peer dependencies — your application supplies a single copy of each.

Import Cinder's global styles once in your application, then import a component from its own subpath:

import '@lostgradient/cinder/styles';
import MarkdownEditor from '@lostgradient/editor/markdown-editor';

<MarkdownEditor id="post-body" value={source} onchange={(next) => (source = next)} />

id is required — MarkdownEditorProps has no default and the component uses it for the accessibility identifiers it renders (labels, aria-* attributes on the editable surface).

Each component ships its own stylesheet, included by the component entry. review-editor also ships its stylesheet as a standalone asset via @lostgradient/editor/review-editor/styles. markdown-editor and diff-viewer style entirely through scoped <style> blocks compiled inline by Svelte — there is no separate /styles subpath for those two.

Components

• @lostgradient/editor/markdown-editor — the rich Markdown editing surface.
• @lostgradient/editor/review-editor — threaded review comments, front matter, and export, composing MarkdownEditor and DiffViewer.
• @lostgradient/editor/diff-viewer — word-level Markdown diffing with front-matter and revert affordances.

Each component subpath also exposes /schema, /variables, and /examples. Only review-editor additionally exposes /styles (see above).

Why a separate package

@lostgradient/cinder used to carry milkdown, prosemirror, and this package's headless runtime as peerDependencies for exactly these three components. Installing Cinder for a <Button> asked your package manager to satisfy a full ProseMirror editor stack. See docs/decisions/package-boundaries.md for the full rationale — this package is Phase 3 of that plan.