Persistent memory for Claude Code — at ~350 tokens ambient cost, with no Docker, no API keys, and no MCP servers. Engram captures your sessions structurally on PreCompact (zero LLM cost), extracts atomic memories via a single lightweight LLM digest (preferences, practices, current context), and detects emergent patterns from your history — files you always edit together, recurring errors, tool usage anomalies — stored as an auditable Obsidian-compatible wiki. Key features: • Per-project handoff notes — at session start you get a narrative message from the last session in this project • Atomic UPSERT memories keyed by topic — latest wins, no drift, no embeddings • Emergent pattern detection (co-edits, error recurrence, project streaks, tool anomalies) • Durable preferences stay global; ephemeral context is scoped per project • 4-flag CLI surface: --stats, --query, --memories, --forget • Everything local: SQLite at ~/.claude/memory.db, markdown wiki at ~/.claude/patterns/