MCP Hangar v1.0 — Production Release

After months of iterative hardening, we are shipping MCP Hangar v1.0 — the first production-grade release of the runtime security and governance layer for MCP servers.

This post covers what MCP Hangar is, what changed since the early prototypes, the architecture that makes it work, and the benchmark numbers that back it up.

What is MCP Hangar?

MCP Hangar sits between AI/LLM tools and the MCP servers they call. It intercepts every tool invocation, applies security policies, propagates caller identity, records a compliance-grade audit trail, and orchestrates parallel execution across MCP servers.

The core use case: you have multiple MCP servers (filesystem, fetch, memory, custom tools), and you need visibility and control over what your AI agents are doing with them. Hangar gives you that without modifying any server code.

The path to v1.0

The project started as a Python library focused on parallel MCP tool execution. Over 22 releases it grew into a multi-component system:

• v0.1 — v0.2: Initial release, event sourcing, observability module, MCP server groups, Langfuse integration. Authentication stack (API keys, JWT/OIDC, RBAC), Kubernetes operator with MCPServer and MCPServerGroup CRDs.
• v0.3 — v0.5: Facade API (Hangar class), batch invocations, SingleFlight deduplication.
• v0.6 — v0.8: Interactive CLI, MCP server bundles, secrets resolver, observability bootstrap, response truncation, tool access filtering with glob patterns, two-level concurrency model.
• v0.9 — v0.12: Security hardening (timing attack prevention, rate limiter backoff, JWT lifetime enforcement, API key rotation), saga persistence, circuit breaker persistence, event store snapshots, K8s operator controllers, REST API with MCP server CRUD, RBAC and tool access policies.
• v1.0: Behavioral profiling with deviation detection, network connection monitoring, tool schema drift detection, resource monitoring, OpenTelemetry governance telemetry, approval gate. Production hardening across the board.

Architecture

The OSS agent (MIT-licensed, pip install mcp-hangar) is the Python core: a runtime proxy that sits between AI tools and MCP servers, intercepts every tool invocation, applies security policies, propagates caller identity, records a compliance-grade audit trail, and orchestrates parallel execution. Domain-driven design with event sourcing, CQRS command/query separation, and single-flight deduplication. It runs anywhere Python runs — laptop, container, Kubernetes pod.

Performance

v1.0 ships with a comprehensive benchmark suite for the Python proxy. The numbers that matter:

Component	Metric	Result
Python proxy	Full path latency (p50 / p99)	0.21ms / 0.24ms
Python proxy	SLA target	20x margin under 5ms

The Python proxy adds less than a quarter-millisecond of overhead at p99. These numbers were measured with pytest-benchmark against the public benchmark suite.

Security

Production readiness means more than performance. v1.0 includes:

• CI security scanning: Trivy filesystem scanning, Semgrep static analysis, and golangci-lint across all components. Pinned to specific versions for reproducible results.
• Dependency auditing: pip-audit for Python, npm audit (blocking on HIGH+) for the web dashboard, govulncheck for Go components. SBOM generation for all components.
• Auth stack coverage: 97.5% test coverage on the authentication and authorization code paths, including API key validation, JWT verification, identity propagation, and rate limiting.
• Upgrade path: A detailed upgrade guide covers every breaking change from v0.12 through v1.0, with step-by-step procedures for PyPI, Docker, and Kubernetes deployments.

Licensing

MCP Hangar is MIT licensed. All features are unconditionally available under the MIT license.

Update (2026-05-17): As of v1.2.2, MCP Hangar is fully MIT-licensed with no restrictions. See the announcement post.

Getting started

Install and run:

curl -sSL https://mcp-hangar.io/install.sh | bash
mcp-hangar serve

Or with pip:

pip install mcp-hangar

Helm charts and a Terraform provider are available for Kubernetes deployments. For simpler setups, run mcp-hangar serve directly or in a container.

Read the full quickstart guide or browse the cookbook for 13 recipes covering everything from HTTP gateway setup to production checklists.

What comes next

The v1.0 release is a foundation. Near-term work includes:

• Security audit hardening: SSRF protection, command allow-list, granular RBAC, WebSocket origin validation (shipped in v1.0.1).
• Observability loop: Cost attribution, compliance export, caller identity in every OTEL span (shipped in v1.1).

Follow the project on GitHub or check the upgrade guide if you are migrating from an earlier version.