Epic: Obsidian-like Note Taking Features

[ElioNeto]

🏔️ Epic: Obsidian-like Note Taking Features

Transform ApexStore into a full-featured note-taking backend capable of powering an Obsidian-like application.

🎯 Objective

Build a complete note storage, indexing, and retrieval layer on top of the existing LSM-Tree engine, enabling wikilinks, backlinks, tags, graph view, full-text search, version history, and real-time sync.

📦 Deliverables

Phase 1 — Core Engine (Backend Storage)

• Core Note Engine Module (NoteParser, NoteIndex, NoteGraph) #276 — Core Note Engine Module (NoteParser, NoteIndex, NoteGraph)
• Wikilink Parser for [[wikilink]] syntax #277 — Wikilink Parser for [[wikilink]] syntax
• Backlink & Forward-link Index #278 — Backlink & Forward-link Index
• Tag Index Engine #279 — Tag Index Engine
• Note Graph View API #280 — Note Graph View API
• REST API for Notes CRUD #281 — REST API for Notes CRUD

Phase 2 — Advanced Features

• Full-text Search for Note Content #283 — Full-text Search for Note Content
• Version History for Notes (Time Travel) #282 — Version History for Notes (Time Travel integration)
• Real-time Sync with CRDT + WebSocket #284 — Real-time Sync with CRDT + WebSocket
• Template Engine for Daily Notes #287 — Template Engine for Daily Notes
• Note Properties / Frontmatter Validation #288 — Note Properties / Frontmatter Validation

Phase 3 — Frontend (Angular)

• Markdown Editor Frontend Component #285 — Markdown Editor Frontend Component
• Graph View Frontend Component #286 — Graph View Frontend Component
• File Explorer / Vault Navigation Frontend #289 — File Explorer / Vault Navigation Frontend

🔗 Dependencies

• Depends on the existing LSM-Tree engine (completed)
• Depends on existing infrastructure: BlobStore, TimeTravelEngine, CRDT, DataSync, PubSub, VectorIndex, MultiModelEngine

📐 Storage Schema Design

// Notes storage using column families
cf "default":
  note:/path/to/note.md  → Markdown content (with frontmatter)
  link:target_note        → [source_note1, source_note2, ...]
  backlink:source_note    → [target_note1, target_note2, ...]
  tag:tagname             → [note_path1, note_path2, ...]
  __blob_meta:asset.png   → Chunk metadata (JSON)
  __blob_chunk:asset.png:0 → Raw bytes

// Time-travel snapshots
snapshot_{timestamp}.json → Full KV snapshot at point in time

// CRDT sync (per-device)
crdt:device_id:note:path  → { value, timestamp }

📊 Key Metrics

• Note write latency: < 50µs (p99)
• Note read latency: < 20µs (p99)
• Full-text search: < 100ms for 10K notes
• Graph view load: < 200ms for 1K connected notes
• Sync convergence: < 2s across devices

🧪 Acceptance Criteria

• All Phase 1 issues are implemented with tests
• REST API allows full CRUD for notes
• Wikilinks are parsed and indexed on write
• Backlinks resolve correctly after renames
• Tags are searchable by prefix
• Graph view returns valid JSON for D3.js/vis.js
• Frontend renders markdown, graph, and file tree
• Version history preserves at least N snapshots
• Sync converges under CRDT merge rules