Cross-platform descendant process tracker that captures and signals process trees using birth identity verification (Linux /proc, Windows creation timestamps, POSIX lstart). Isolates process group cleanup logic from the rest of the runtime, making it reusable for any application needing reliable child process lifecycle management.

Generic DAG executor (FlowRunner) that runs flow definitions composed of acp, compute, action, shell, and checkpoint nodes. Supports timeout, heartbeat, cancellation, session binding, and node-level error handling. The node type system and edge routing are decoupled from specific agent logic, enabling reuse in any multi-step workflow engine.

Append-only event log writer and reader with segment rotation, cursor-based replay, and corruption detection. Used for session journaling but designed as a standalone component that could be extracted for any application requiring durable, sequential event storage with bounded file sizes.

Pure function reducer that transforms ACP session updates (text deltas, tool calls, usage, mode changes) into a normalized conversation model. Handles all ACP update types with deep cloning and safe property access, making it reusable for any system that needs to maintain a lossless, bounded conversation state from a stream of events.

Permission resolution pipeline that supports three modes (approve-all, approve-reads, deny-all), rule-based policy matching with auto-approve/deny/escalate, and fallback to interactive prompts. The mode→policy→escalation→prompt chain is cleanly separated, allowing reuse in any CLI or daemon that needs configurable access control for tool calls.