Quiche is Cloudflare's implementation of the QUIC transport protocol and HTTP/3, written in Rust and specified according to IETF standards. The library provides a low-level API for processing QUIC packets and managing connection state, while delegating I/O operations and event loop management to the application layer. This design gives developers flexibility in how they integrate quiche with their specific networking frameworks and requirements.
The library has achieved significant real-world adoption. Cloudflare uses quiche to power HTTP/3 support across its edge network, with the cloudflare-quic.com website available for testing and experimentation. Android's DNS resolver integrates quiche to implement DNS over HTTP/3, and curl can be integrated with quiche to provide HTTP/3 support. These deployments demonstrate the library's production readiness and broad applicability across different use cases.
Quiche's API design emphasizes explicit configuration of connection parameters. The Config object controls critical aspects including QUIC version, ALPN IDs, flow control, congestion control, and idle timeout. Notably, quiche defaults several stream and data limit properties to zero, requiring applications to explicitly set values appropriate for their use case through methods like set_initial_max_streams_bidi, set_initial_max_streams_uni, and set_initial_max_data. This approach ensures applications consciously consider their specific requirements rather than relying on potentially inappropriate defaults.
The library provides both Rust and C APIs. The C API is a thin wrapper over the Rust implementation, enabling integration into C and C++ applications through FFI mechanisms. When building with the ffi feature enabled, cargo automatically produces a standalone libquiche.a static library suitable for direct linking into C/C++ applications. This dual-API approach significantly broadens quiche's accessibility beyond Rust-only projects.
Quiche includes an HTTP/3 module that provides higher-level abstractions for sending and receiving HTTP requests and responses over QUIC. The library also offers command-line tools through the quiche-apps crate for testing and experimentation, though these are explicitly not intended for production use. The repository includes comprehensive examples demonstrating both Rust and C/C++ integration patterns.
The project maintains active development with median issue and pull request response latency of 33.4 hours across 227 tracked items, though mean latency is significantly higher at 8278.5 hours, indicating some older items receive delayed attention. The most active contributor tracked is ghedo with 211 events, followed by LPardue with 165 events. Nginx-related issues represent the most common label with 12 occurrences. The repository shares contributors with microsoft/vscode, rust-lang/rust, and microsoft/typescript, indicating cross-project collaboration within the broader Rust and web standards communities.
Building quiche requires Rust 1.88 or later and automatically handles BoringSSL compilation for TLS cryptographic operations. The project supports building for multiple platforms including Android with NDK 19 or higher and iOS with appropriate Rust toolchains. Docker images are available for both standard quiche deployment and QUIC interoperability testing through the quic-interop-runner framework.
