Arti is an official Tor Project initiative to rewrite the Tor client stack in Rust. Its primary goal is to address long-standing safety, reliability, and maintainability challenges inherent in the legacy C-based Tor implementation. By leveraging Rust’s strong compile-time guarantees for memory safety and concurrency, Arti eliminates entire classes of bugs that have historically affected Tor, including many security vulnerabilities.

Arti is architected as a modular, embeddable library rather than a monolithic application. This makes it easier for developers to integrate Tor networking capabilities directly into other applications, services, and platforms. From its earliest versions, Arti has supported multi-core cryptography, cleaner APIs, and a more maintainable internal design.

While early releases focused on client functionality such as bootstrapping, running as a SOCKS proxy, and routing traffic over the Tor network, the long-term roadmap includes full feature parity with the existing Tor client, support for onion services, anti-censorship mechanisms, and eventually Tor relay functionality. Arti represents the future foundation of the Tor ecosystem, prioritizing long-term security, developer velocity, and adaptability.

Tor Goes Rust: Introducing Arti, a New Foundation for the Future of Tor