This is the official NATS C client library (nats.c), a production-grade C library providing full support for the NATS messaging system. It implements core publish/subscribe, request-reply, queue groups, and advanced features including JetStream (streams, consumers, key-value store, object store), a microservices framework, and legacy NATS Streaming support. The library is designed for high performance and reliability, with built-in reconnection, TLS/SSL, authentication (NKeys, JWT), and event loop integration (libevent, libuv). It exposes a comprehensive C API with hundreds of functions, and includes extensive examples and documentation. The codebase is well-structured with platform abstractions for Unix and Windows, and internal modules for protocol parsing, connection management, threading, and memory management. While the library is actively maintained and widely used, it carries some technical debt from legacy Streaming support and a large, tightly-coupled internal architecture.
RMQTT is a high-performance, distributed MQTT broker written in Rust, supporting MQTT v3.1, v3.1.1, and v5.0 protocols. It provides TCP/TLS/WebSocket/QUIC transports, a plugin-based extensibility system, multiple clustering modes (broadcast and Raft), persistent session and message storage (sled, Redis), authentication via HTTP or JWT, ACL rules, and bridges to Kafka, Pulsar, NATS, and ReductStore. The broker includes a built-in HTTP management API with a Vue.js dashboard and a comprehensive test suite covering conformance, stress, and chaos scenarios. Production features include circuit breakers, rate limiting, metrics export, and configuration-driven operation. The codebase is well-structured with clean abstractions, reusable components (codec, network builder, hook system), and active maintenance, though the dual clustering implementations and extensive feature flags introduce some complexity.
This repository is a comprehensive tutorial on building AI agent harnesses, structured as 17 progressive lessons. Each lesson introduces a single mechanism (tool use, permissions, hooks, planning, subagents, skill loading, context compaction, memory, task system, background tasks, cron scheduler, agent teams, MCP integration, workflow runtime, and goal loop) that extends a core agent loop without modifying it. The harness enables a language model (Claude) to perceive, reason, and act through tool interactions while managing context, permissions, and collaboration. The repository includes runnable Python implementations for each lesson and an interactive Next.js web application with visualizations for learning and experimentation.
Iodine is a high-performance concurrent web server for Ruby applications, built as a wrapper around the C-based facil.io framework. It provides native HTTP/WebSocket/Server-Sent Events support, Rack compliance for serving Ruby web applications, and a built-in Pub/Sub system with optional Redis scaling for horizontal distribution. The architecture follows a master-worker model using multiple processes and threads to handle thousands of concurrent connections, with critical networking components implemented in C for performance and Ruby bindings for developer productivity. Key features include static file serving with gzip and X-Sendfile support, a secure Mustache template engine with automatic HTML escaping, a fast JSON parser claiming 20-90% speed improvements over Ruby's standard library, and TLS support (though marked as having known issues for production use). The server integrates with Rack applications through a custom handler and provides upgrade hooks for WebSocket/SSE protocols via the Rack environment. Pub/Sub functionality uses an engine pattern allowing swap between internal cluster-based and external Redis backends. Entry points include the `exe/iodine` CLI executable and programmatic controls via `Iodine.listen`, `Iodine.start`, and `Iodine.stop`. Data flows involve HTTP requests parsed by the C-based HTTP processor, routed to Rack applications or static file handlers, with WebSocket connections upgraded via Rack's `env['rack.upgrade?']` mechanism. The Pub/Sub system operates independently for real-time messaging across processes or machines. External dependencies include the vendored facil.io C library, OpenSSL development headers for TLS support, and optionally the Redis gem for clustered Pub/Sub.
VOLTTRON is a Python-based distributed control and integration platform for building and industrial control systems. It runs cooperating 'agents' (services) that communicate over a ZeroMQ/RabbitMQ message bus called VIP, supporting pub/sub, RPC, and peer-to-peer routing. The platform provides agent lifecycle management (volttron-ctl), a web UI, authentication, historians, and protocol drivers for Modbus, BACnet, and similar field protocols. In production it acts as a central hub for collecting sensor/controller data, executing actuation commands, and hosting automation logic.