@robonen/writekit

A headless, block-based rich-text writekit for Vue 3 — in the spirit of Tiptap / ProseMirror / Editor.js, but with a hand-built CRDT for collaboration (no Yjs/Loro/Automerge).

• Block registry + schema — blocks and inline marks are modular, registered through a registry that projects an immutable schema.
• Single contenteditable — one editable surface (ProseMirror/Tiptap model), so native cross-block mouse selection and arrow navigation behave like a normal document.
• Framework-agnostic core — the model, schema, registry, state, commands and keymap are DOM-free and Vue-free; the Vue layer is only rendering + input.
• Step-based transactions with exact inverses → real undo/redo, and the same steps drive the CRDT.
• Own CRDT (@robonen/crdt) behind a pluggable CrdtProvider — RGA text, fractional-indexed blocks, Peritext-style marks, version-vector sync, presence/cursors.

Status: v0 / work in progress. Logic is covered by unit + convergence tests; the contenteditable/Playwright tests run locally (not in CI sandboxes).

Install

pnpm add @robonen/writekit @robonen/crdt vue

Quick start

<script setup lang="ts">
import { createDefaultRegistry, createWritekit, createWritekitState, WritekitRoot } from '@robonen/writekit';

const registry = createDefaultRegistry();
const writekit = createWritekit({ state: createWritekitState({ registry }) });
</script>

<template>
  <WritekitRoot :writekit="writekit" autofocus class="writekit" />
</template>

WritekitRoot's default slot renders WritekitContent (the single contenteditable). Provide your own slot to add UI around it:

<WritekitRoot :writekit="writekit" autofocus>
  <WritekitContent />
  <WritekitBubbleMenu />   <!-- formatting toolbar on selection -->
  <WritekitSlashMenu />    <!-- `/` to insert blocks -->
</WritekitRoot>

The package is headless: it ships behavior and DOM structure (data-block-*, data-writekit-* hooks), not styling. See playground/src/App.vue for a complete stylesheet.

Blocks & marks

Built-in blocks (via createDefaultRegistry()): paragraph, heading (1–6), bulleted-list / numbered-list / todo-list (flat-with-indent), blockquote, code-block, callout, divider, image. Built-in marks: bold, italic, underline, strike, highlight, code, link.

Add your own — no core changes needed:

import { createRegistry, defineBlock, defineMark, defaultBlocks, defaultMarks } from '@robonen/writekit';

const spoiler = defineMark({
  type: 'spoiler',
  spec: { toDOM: () => ['span', { 'data-spoiler': '' }, 0], parseDOM: [{ tag: 'span[data-spoiler]' }] },
});

const registry = createRegistry({ blocks: defaultBlocks, marks: [...defaultMarks, spoiler] });

Editing UX

• Slash menu — WritekitSlashMenu: type / at the start of a line; items come from each block's meta.
• Bubble toolbar — WritekitBubbleMenu: floats over a text selection (positioned with @floating-ui/vue); override the buttons via its default slot (#default="{ active, toggle }").
• Markdown input rules — # →heading, - /* →bulleted list, 1. →numbered list, > →quote, [] →to-do.
• Drag to reorder — pass draggable to WritekitRoot for per-block drag handles.
• Hotkeys — Mod-b/i/u, Mod-Shift-s (strike), Mod-e (code), Mod-z / Mod-Shift-z, Enter (split), Shift-Enter (hard break), Backspace/Delete at edges (merge), Mod-a (progressive select), Mod-Alt-1..6 (heading), Tab/Shift-Tab (list indent).

Commands

Commands are (state, dispatch?, view?) => boolean and power the keymap, UI, and programmatic edits:

import { toggleMark, setBlockType } from '@robonen/writekit';

writekit.command(toggleMark('bold'));
writekit.command(setBlockType('heading', { level: 2 }));

Called without dispatch they are a dry run (for disabled/active toolbar state).

Collaboration (own CRDT)

The writekit is CRDT-agnostic behind CrdtProvider. The built-in provider maps writekit steps to CRDT ops (blocks → fractional-indexed set, text → RGA, formatting → mark store) and syncs op batches over any transport.

import { bindCrdt, createNativeProvider } from '@robonen/writekit';

// First peer seeds the document.
const provider = createNativeProvider({ schema: registry.schema, doc: writekit.state.doc, user: { name: 'Alice', color: '#2563eb' } });
const binding = bindCrdt(writekit, provider);

// Wire a transport (BroadcastChannel / WebSocket / …):
provider.onLocalOps(bytes => channel.postMessage(bytes));
channel.onmessage = e => provider.applyUpdate(e.data);

// A joining peer starts empty and syncs:
//   const provider = createNativeProvider({ schema });
//   provider.applyUpdate(remoteFullState);   // = peerA.encodeDelta()

Presence/cursors travel on a separate ephemeral channel and render with WritekitRemoteCursors:

provider.onLocalAwareness(bytes => channel.postMessage(bytes));
const cursors = ref([]);
provider.onAwareness(next => cursors.value = next);

<WritekitRoot :writekit="writekit">
  <WritekitContent />
  <WritekitRemoteCursors :cursors="cursors" />
</WritekitRoot>

See the Collaboration demo in the playground for a full two-replica example.

Applying a remote change is per-block: bindCrdt reuses the node identity of every block a remote edit didn't touch, so only changed blocks repaint and the local caret in untouched blocks is undisturbed.

For long-lived sessions, compact tombstones once the replicas are quiesced and fully synced:

provider.gc(); // drops deleted characters / removed blocks safe to forget

Known limitations (documented, deferred)

• A local caret does not auto-shift when a remote peer inserts text before it (the caret keeps its offset).
• Concurrent split/merge of the exact same range can drop a mark recreated on the moved tail.
• gc() is only safe at quiescence (no in-flight ops) — it has no built-in stability protocol; drive it from your sync layer.

Development

pnpm --filter @robonen/writekit test          # logic (jsdom) + CRDT convergence
pnpm --filter @robonen/writekit build         # tsdown (ESM + CJS + dts)
pnpm --filter @robonen/writekit-playground dev

See AGENTS.md for the architecture and contributor notes.