Roadmap to MVP

A linear checklist of milestones between now and shipping.

Last updated: 2026-02-10

Model: Zus is a local-first writing app. It's all local-first.

1. Browser Mode — works instantly, no install, no account (MVP)
2. Sync Mode — Cloud Sync (sign in) + Desktop Sync (app store adapter)
3. Desktop App — Electron, built-in sync + filesystem (power users)

Canonical format: CRDT (Y.XmlText encoding the Slate AST). Markdown is an import/export format. See pm/specs/document-sync-architecture.md.

Done

• CRDT-native document model — Single Slate editor per document. One Y.XmlText per document. @slate-yjs/core maps Slate ↔ Yjs. Markdown adapter (unified/remark) for import/export.
• Yjs CRDT integration — Y.Doc per document, withYjs/withYHistory in editor, IndexedDB persistence (binary Y.Doc state). Collab-ready foundation.
• Plugin system core — Plugin registry with install/uninstall lifecycle, dependency checking, conflict detection. CommandRegistry for commands. BlockRendererRegistry for block types.
• Obsidian-inspired plugin API — onload(api) / onunload() lifecycle. PluginAPI context with addCommand(), registerBlockType(), registerEvent(), addStatusBarItem(), loadData()/saveData(). Auto-cleanup on uninstall. Event bus for plugin event dispatching.
• Error handling — Custom error hierarchy, React error boundaries, auto-save retry with exponential backoff.
• Reference plugins — Formatting (bold/italic/underline/code/link), Headings (h1/h2/h3), Word Count. All use onload(api) pattern.
• Editor wiring + plugin validation — Keyboard shortcuts (Cmd+B/I/U/K) fire through command registry. onChange flows to event bus (word count updates live). Format toolbar appears on text selection. Image elements render from markdown. Full plugin loop validated.
• Plugin tier system — Three tiers (system/core/community) with distinct API surfaces. System plugins (shell, AI agent, editor) get SystemPluginAPI with workspace-level access. Core/community plugins use standard PluginAPI. Everything with a lifecycle is a plugin.
• Sync server prototype — Bun-based Yjs sync server with file watcher, Y.XmlText ↔ markdown bridge (slate-bridge.ts), WebSocket sync protocol. Validates the sync architecture.

Next — Browser Mode (MVP)

• Wire YjsDocumentProvider into EditorPanel — Y.Doc from IndexedDB is the document. No separate loadDocument / initialDocument path. No WebSocket sync for MVP.
• Editor library — Pure editor commands, keymap system (including vim mode), selection utilities, structural analysis (outline, sections, references). Being built in core/src/editor/ as library code, then wired into plugins. (in progress)
• Shell architecture — View system, navigation model, surfaces. Sidebar, omnibar, status line as pluggable surfaces. Shell itself is a system plugin.
• Theme system — Light/dark/system modes, font style, size, width, spacing. CSS custom properties. Settings persistence.
• AI agent integration ("Zus") — Plugin shape and shell surface for the AI mediator. Contextual writing assistance within the editing flow.
• Search — Document search across the user's space. Omnibar as the search surface.
• Ship Browser Mode MVP

Later — Sync Mode

• Auth — iCloud and Google sign-in (no email/password). Account is optional — app works fully without it.
• Cloud Sync — Cloudflare Durable Objects for document sync. Each doc = one DO (durable replica). WebSocket transport via useYjsWebSocketSync. Browser → sign in → existing docs sync seamlessly (Yjs merge).
• AI agents via MCP — MCP server exposing fine-grained CRDT operations. Agents make surgical edits that merge with concurrent human edits.
• Desktop Sync — Native adapter (app store). Connects to DO as Yjs peer. Writes .md files to disk via markdown adapter.

Later — Desktop App

• Electron app — Native app with built-in cloud sync + filesystem access. Same editor, same CRDT. Prototype exists at packages/desktop.

Specs Index