MockServer is a highly sophisticated, multi-protocol HTTP(S) mock server and proxy for testing, written in Java with Netty. It supports HTTP/1.1, HTTP/2, HTTP/3 (QUIC), gRPC, WebSockets, DNS, TCP, and binary protocols on a single port. The core engine provides expectation-based request matching, response generation, forwarding, proxying, recording, verification, and chaos engineering (latency, connection drops, error injection). It also includes built-in LLM mocking (OpenAI, Anthropic, Gemini, etc.), OIDC/OAuth2/SAML identity providers, SCIM provisioning, WASM custom rules, and drift detection. The repository is a monorepo containing the Java server, multi-language client libraries (Java, Node, Python, Ruby, Go, .NET, Rust, PHP), a React dashboard UI, IDE plugins (JetBrains, VS Code), Helm charts, Docker images, and extensive CI/CD pipelines via Buildkite. The architecture is modular with clear separation of concerns: core model/matcher/serialization in `mockserver-core`, Netty transport in `mockserver-netty`, language-specific clients in `mockserver-client-*`, and a React UI in `mockserver-ui`. The codebase demonstrates strong engineering practices including DTO patterns with Jackson serializers, a matcher hierarchy with compiled-once validators, bounded caches, constant-time equality checks, and extensive test coverage with integration tests across multiple environments.
chaoskube is a Kubernetes chaos engineering tool that periodically terminates random pods in a cluster. It runs as a long-lived process (deployment or CLI) and uses the Kubernetes API to list, filter, and delete pods. The architecture is a single binary with a main entry point that wires together configuration (flags/env vars), a Kubernetes client, pod filters (labels, annotations, namespaces, kinds, name regex, age, time-based exclusions), a terminator (currently only delete-pod), and optional notifiers (Slack). The core loop in `chaoskube.Run()` ticks on a configurable interval, calls `TerminateVictims()` which checks time-based exclusions, selects victims via `Victims()` (which calls `Candidates()` applying all filters), and deletes them. The code is well-structured with clear interfaces for termination and notification, comprehensive test coverage using fake Kubernetes clients, and a Helm chart for deployment. It is a mature, actively maintained project with 1935 stars and a strong community.