Seastar is a high-performance C++ asynchronous framework built on a shared-nothing, reactor-based architecture. It provides core primitives like futures/promises, coroutine support, per-CPU sharding, and a sophisticated I/O scheduler with fair queuing and token-bucket throttling. The framework includes a production-grade networking stack (TCP, UDP, TLS, HTTP, WebSocket, RPC), a custom memory allocator, comprehensive metrics (Prometheus, collectd), and extensive testing/benchmarking infrastructure. Seastar is used by real-world systems such as ScyllaDB, Redpanda, and Ceph Crimson. The codebase is mature, but exhibits some technical debt in the form of deprecated API usage, platform-specific workarounds, and a few license inconsistencies. Overall, it represents a strong example of systems-level C++ engineering with reusable algorithmic components and a well-documented architecture.
vkbottle is an asynchronous Python framework for building VK (VKontakte) bots and interacting with the VK API. It provides both high-level abstractions (Bot, User, labelers, rules, middlewares, state dispensers) and low-level API clients with pluggable request/response validation, token rotation, and error handling. The framework is fully async, built on asyncio and aiohttp, and supports long polling, callback API, and dual mode (simultaneous polling and callback). It includes extensive tooling for keyboards, templates, uploaders, markdown-to-VK-format conversion, VKScript generation, event deduplication, and a waiter machine for awaiting future events. The architecture is modular with abstract base classes for nearly every component, enabling custom implementations. The codebase is well-structured with clear separation of concerns, extensive test coverage, and CI/CD pipelines. Deprecated components (LoopWrapper, Blueprints) are clearly marked, and the library is actively maintained with a mature version 4.11.0.