5498ec5a6d
Created four issues to address N-way collision limitations: - bd-109: Add transaction + retry logic (P1, immediate fix) - bd-110: Implement clone-scoped ID allocation (P2, medium-term) - bd-111: Investigate jujutsu VCS for better merging (P2, research) - bd-112: CRDT-based architecture for v2.0 (P3, long-term) These address the KNOWN LIMITATION documented in beads_nway_test.go where 5+ clone collisions fail during convergence with UNIQUE constraint violations. 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude <noreply@anthropic.com>
2 lines
3.8 KiB
JSON
2 lines
3.8 KiB
JSON
{"id":"bd-112","content_hash":"512f36b6f06a2a94fad45beb3a254f824401d967ac5bf402ebcf9eb3830b2186","title":"CRDT-based architecture for guaranteed convergence (v2.0)","description":"## Vision\nRedesign beads around Conflict-Free Replicated Data Types (CRDTs) to provide mathematical guarantees for N-way collision resolution at arbitrary scale.\n\n## Current Limitations\n- Content-hash based collision resolution fails at 5+ clones\n- Non-deterministic convergence in multi-round scenarios\n- UNIQUE constraint violations during rename operations\n- No formal proof of convergence properties\n\n## CRDT Benefits\n- Provably convergent (Strong Eventual Consistency)\n- Commutative/Associative/Idempotent operations\n- No coordination required between clones\n- Scales to 100+ concurrent workers\n- Well-understood mathematical foundations\n\n## Proposed Architecture\n\n### 1. UUID-Based IDs\nReplace sequential IDs with UUIDs:\n- Current: bd-1, bd-2, bd-3\n- CRDT: bd-a1b2c3d4-e5f6-7890-abcd-ef1234567890\n- Human aliases maintained separately: #42 maps to UUID\n\n### 2. Last-Write-Wins (LWW) Elements\nEach field becomes an LWW register:\n- title: (timestamp, clone_id, value)\n- status: (timestamp, clone_id, value)\n- Deterministic conflict resolution via Lamport timestamp + clone_id tiebreaker\n\n### 3. Operation Log\nTrack all operations as CRDT ops:\n- CREATE(uuid, timestamp, clone_id, fields)\n- UPDATE(uuid, field, timestamp, clone_id, value)\n- DELETE(uuid, timestamp, clone_id) - tombstone, not hard delete\n\n### 4. Sync as Merge\nSyncing becomes merging two CRDT states:\n- No merge conflicts possible\n- Deterministic merge function\n- Guaranteed convergence\n\n## Implementation Phases\n\n### Phase 1: Research \u0026 Design (4 weeks)\n- Study existing CRDT implementations (Automerge, Yjs, Loro)\n- Design schema for CRDT-based issue tracking\n- Prototype LWW-based Issue CRDT\n- Benchmark performance vs current system\n\n### Phase 2: Parallel Implementation (6 weeks)\n- Implement CRDT storage layer alongside SQLite\n- Build conversion tools: SQLite ↔ CRDT\n- Maintain backward compatibility with v1.x format\n- Migration path for existing databases\n\n### Phase 3: Testing \u0026 Validation (4 weeks)\n- Formal verification of convergence properties\n- Stress testing with 100+ clone scenario\n- Performance profiling and optimization\n- Documentation and examples\n\n### Phase 4: Migration \u0026 Rollout (4 weeks)\n- Release v2.0-beta with CRDT backend\n- Gradual migration from v1.x\n- Monitoring and bug fixes\n- Final v2.0 release\n\n## Risks \u0026 Mitigations\n\n**Risk 1: Performance overhead**\n- Mitigation: Benchmark early, optimize hot paths\n- CRDTs can be slower than append-only logs\n- May need compaction strategy\n\n**Risk 2: Storage bloat**\n- Mitigation: Implement operation log compaction\n- Tombstone garbage collection for deleted issues\n- Periodic snapshots to reduce log size\n\n**Risk 3: Breaking changes**\n- Mitigation: Maintain v1.x compatibility layer\n- Gradual migration tools\n- Dual-mode operation during transition\n\n**Risk 4: Complexity**\n- Mitigation: Use battle-tested CRDT libraries\n- Comprehensive documentation\n- Clear migration guide\n\n## Success Criteria\n- 100-clone collision test passes without failures\n- Formal proof of convergence properties\n- Performance within 2x of current system\n- Zero manual conflict resolution required\n- Backward compatible with v1.x databases\n\n## Timeline\n18-20 weeks total (4-5 months)\n\n## References\n- Automerge: https://automerge.org\n- Yjs: https://docs.yjs.dev\n- Loro: https://loro.dev\n- CRDT theory: Shapiro et al, A comprehensive study of CRDTs\n- Related issues: bd-109, bd-110, bd-111","status":"open","priority":3,"issue_type":"feature","created_at":"2025-10-29T10:23:57.978339-07:00","updated_at":"2025-10-29T10:23:57.978339-07:00"}
|