s2n-tls is a C99 implementation of the TLS/SSL protocols designed by AWS for simplicity, small size, and security. It supports TLS 1.2 and 1.3, including features like 0-RTT early data, session tickets, post-quantum KEMs (ML-KEM, ML-DSA), and QUIC transport integration. The library provides a public C API (api/s2n.h) and multiple libcrypto backends (OpenSSL, AWS-LC, BoringSSL, LibreSSL). Extensive formal verification (CBMC, SAW, SideTrail) and fuzz testing ensure memory safety and constant-time execution. The architecture is highly modular with a stuffer buffer abstraction, blob/array utilities, a table-driven TLS extension framework, and a robust error-handling macro system. Rust bindings are first-class, offering safe wrappers (s2n-tls), async Tokio integration (s2n-tls-tokio), an HTTP client connector for Hyper (s2n-tls-hyper), and a metrics subscriber for handshake analysis. The library is used by AWS services like S3 and KMS, and includes interoperability tests against OpenSSL, GnuTLS, Java, and rustls. It is actively maintained with a sophisticated CI pipeline covering unit, integration, fuzz, formal proof, and performance regression tests across multiple platforms and libcrypto versions.
Flecs is a high-performance Entity Component System (ECS) framework for games and simulations, written in C99 with a C++17 wrapper. It provides a data-oriented storage model where entities are stored in archetype tables with component columns, enabling cache-efficient iteration. The framework includes a powerful query language with support for relationships, inheritance, traversal, grouping, and sorting. It features an extensive addon system covering systems (pipelines), observers, prefabs, reflection/meta, JSON serialization, an embedded scripting language (Flecs Script) with async/await, a REST API with an HTTP server, statistics/metrics, alerts, and more. Flecs has zero external dependencies and is designed for lockless multi-core scheduling. It is used in commercial games and has a large ecosystem of examples and community bindings. Architecture: The library is modular with a core C API and optional addons compiled via preprocessor flags. The C++ API provides a fluent builder pattern for constructing entities, systems, queries, and observers. Key entry points include ecs_init/flecs::world for world creation, ecs_progress for running the game loop, ecs_insert for entity creation, ecs_system for defining systems, ecs_query for cached queries, and ecs_script for running Flecs Script files. Data flows involve creating entities with components, which are stored in tables; systems iterate over matching entities each frame; observers react to component changes; and the script engine allows runtime entity manipulation. External dependencies: None. Flecs is self-contained and uses only standard C library functions.
cgltf is a single-file, stb-style C library for parsing and writing glTF 2.0 files. It provides a comprehensive set of data structures mirroring the glTF spec, along with functions to parse JSON/GLB, load buffers, validate data, and write back glTF/GLB. The library is self-contained, requires no external dependencies, and includes an embedded copy of the JSMN JSON parser. It supports core glTF 2.0 and many extensions (KHR_materials_*, KHR_lights_punctual, EXT_mesh_gpu_instancing, etc.). The code is well-structured, uses C99, and is designed for easy integration into any C or C++ project. It is used by major projects like bgfx, Filament, and raylib. The writer component (cgltf_write.h) is separate but similarly crafted. The repository includes a comprehensive test suite and fuzz testing setup.
This repository is a curated, structured dataset of C and C++ standard features (from C99 to C++29) with per-compiler support status across multiple toolchains (GCC, Clang, MSVC, Xcode, etc.). It includes YAML data files defining features, toolchain releases, and frontend metadata, along with a C++ validation tool that enforces schema compliance and semantic consistency (e.g., verifying that referenced tool versions exist and issue trackers are properly used). The dataset is designed to power a reference website (cppstat) and is accompanied by detailed Markdown explanations for each feature. While the primary artifact is the data itself, the validator and CI pipeline demonstrate strong data engineering practices, making the repository a reliable source for compiler feature support information.