tonic 0.6.2

A gRPC over HTTP/2 implementation focused on high performance, interoperability, and flexibility.

A Rust implementation of gRPC, a high performance, open source, general RPC framework that puts mobile and HTTP/2 first.

tonic is a gRPC over HTTP/2 implementation focused on high performance, interoperability, and flexibility. This library was created to have first class support of async/await and to act as a core building block for production systems written in Rust.


Examples can be found in the tonic-examples crate.

Getting Started

Follow the instructions in the tonic-build crate documentation.

Feature Flags

  • transport: Enables the fully featured, batteries included client and server implementation based on hyper, tower and tokio. Enabled by default.
  • codegen: Enables all the required exports and optional dependencies required for tonic-build. Enabled by default.
  • tls: Enables the rustls based TLS options for the transport feature. Not enabled by default.
  • tls-roots: Adds system trust roots to rustls-based gRPC clients using the rustls-native-certs crate. Not enabled by default. tls must be enabled to use tls-roots.
  • tls-webpki-roots: Add the standard trust roots from the webpki-roots crate to rustls-based gRPC clients. Not enabled by default.
  • prost: Enables the prost based gRPC Codec implementation.
  • compression: Enables compressing requests, responses, and streams. Note that you must enable the compression feature on both tonic and tonic-build to use it. Depends on flate2. Not enabled by default.


Generic implementation

The main goal of tonic is to provide a generic gRPC implementation over HTTP/2 framing. This means at the lowest level this library provides the ability to use a generic HTTP/2 implementation with different types of gRPC encodings formats. Generally, some form of codegen should be used instead of interacting directly with the items in client and server.


The transport module contains a fully featured HTTP/2.0 Channel (gRPC terminology) and Server. These implementations are built on top of tokio, hyper and tower. It also provides many of the features that the core gRPC libraries provide such as load balancing, tls, timeouts, and many more. This implementation can also be used as a reference implementation to build even more feature rich clients and servers. This module also provides the ability to enable TLS using rustls, via the tls feature flag.