v0.2.1

New Features

• MCP Client: Model Context Protocol client implementation with JSON-RPC 2.0 messaging, stdio and SSE transport support, tool schema management, and connection lifecycle management.
• Web Dashboard: Real-time monitoring dashboard with WebSocket hub, REST API v2, orchestrator for multi-agent coordination, event bridge for system state streaming, and static asset serving.
• Flight Recorder: Multi-agent runtime intelligence recording with timeline tracking, decision logging, diagnostics engine, agent genealogy graph, DOT/JSON export, and replay pipeline.
• Chaos Engineering Arena: Fault injection framework with injector supporting process_kill, network_partition, latency_spike, and kill_orchestrator fault types; resilience scoring with configurable metrics; survival mode for continuous chaos testing; HTTP API and YAML scenario configuration.
• Callbacks System: Event-driven callback mechanism with typed event contexts, handler registry, and lifecycle hooks for agent/tool/runtime events.
• LLM Output Parsing: Multi-provider output adapters (OpenAI, Ollama, OpenRouter), prompt template engine with Go template syntax, function calling extraction and validation, schema-based parameter validation, and streaming output parser.
• Function Calling: LLM function calling support with tool schema generation, argument extraction, and result formatting.
• Agent Genealogy: Agent lineage tracking with parent-child relationships, birth/death event recording, and genealogy graph export.
• Event Auto-Compaction: Configurable event store compaction with retention policies, snapshot-based trimming, and automatic execution.
• Tool Lifecycle Hooks: Pre/post execution hooks for tools with context injection and error handling.
• Quant Demo: Quantitative analysis example with CSV data processing.
• DevAgent Example: Development agent example with workflow configuration.
• MCP Dashboard Example: Dashboard integration example with MCP transport.
• Capability Demo: Tool capability demonstration example.

Improvements

• Pruned unused components and deduplicated code across runtime resurrection module
• Improved error visibility with structured error messages
• Extracted restore logic into reusable functions
• Exposed migration DDL for external tooling
• Cleaned up validators and reduced code duplication
• Streamlined dashboard frontend assets
• Generalized domain models for broader use cases beyond original fashion domain

Bug Fixes

• Fixed various lint issues identified by golangci-lint
• Added GetAgent method to Runtime interface
• Wired verifyRestoredState in example code
• Corrected semaphore available count calculation
• Escaped password in DSN connections
• Added ILIKE pattern escaping for PostgreSQL queries

v2.0.0 (2026-06-11)

New Features

• Leader Failover: Checkpoint-based recovery with LeaderSupervisor detecting leader failure, recovering stale tasks from last checkpoint, and reassigning work to available sub-agents. ColdRestartStrategy for deterministic recovery.
• Runtime Dynamic Graph: MutableDAG with thread-safe mutation (add/remove nodes and edges at runtime). DynamicExecutor with ApplyMode for hot-reload without stopping execution. Incremental cycle detection on edge insertion.
• Human-in-the-Loop: InterruptConfig on workflow steps for human approval gates. InterruptHandler blocks execution until approved. InterruptStore provides crash recovery of pending approvals.
• Agent Resurrection Plugin: Pluggable HealthChecker interface for custom health detection. HeartbeatAdapter for heartbeat-based liveness. Supervisor for automatic agent restart on failure.
• Event Sourcing: EventStore interface with optimistic concurrency control. MemoryEventStore for dev/test, PostgresEventStore for production. 17 event types covering agent lifecycle, tasks, sessions, workflows, and failover. Pub/sub via Subscribe with filtered event channels. DLQ auto-retry with configurable retry budgets.
• Pluggable Vector Store: VectorStore interface replacing concrete *VectorSearcher in Repository. PostgreSQL + pgvector for production, in-memory for dev/test. Drop-in replacement support for Qdrant, Milvus, SQLite, or custom backends.
• WorkflowService API: High-level workflow orchestration abstraction over the DAG engine.

Bug Fixes (46 fixes)

Storage (12 fixes)

• C1: Embedding queue dedup key mismatch causing duplicate embeddings
• C2: Write buffer data loss on Stop() before flush completes
• C3: Embedding enqueue outside transaction leading to orphaned records
• C4: FetchPendingTasks lock ineffective with FOR UPDATE SKIP LOCKED
• C5: Reconcile threshold time arithmetic off by orders of magnitude
• M1: ManagedRow connection leak on error paths
• M2: Missing migration tables in migrate.go
• M3: Circuit breaker halfOpenInflight counter leak
• M4: VectorSearcher missing dimension validation
• M6: FileWatcher TOCTOU race in scanAndLoad
• M7: Map reference shared unsafely in callbacks
• M8: Graph Edge() no validation of node endpoints

Workflow (8 fixes)

• C6: Panic recovery ordering in executor.go (recovery after cleanup)
• C7: Graph executor in-degree tracking incorrect after node removal
• H1: Deadlock false positive in executor.go (errgroup misuse)
• H2: DynamicExecutor hang on node removal during execution
• H3: stepEg.Wait() concurrent with Go() causing race
• H4: NewDAG silently dropping duplicate step IDs
• M5: MaxAttempts=0 skips execution entirely
• M9: recomputeOrder version-check race on concurrent access

AHP Protocol (7 fixes)

• C8: Queue send on closed channel panic during shutdown
• C9: HeartbeatSender Start/Stop race condition
• H5: getRandomSuffix nil dereference on empty slice
• H6: SendMessage swallows all errors silently
• H7: Protocol has no Close() method (resource leak)
• M10: Peek() non-atomic read (race under concurrent access)
• M12: DLQ.Remove leaks trailing pointer after deletion

What's Changed

• v0.2.1 by @Timwood0x10 in #30

Full Changelog: v0.2.0...v0.2.1