iroh reaches first 1.0 release candidate after four years of work

iroh has crossed into release-candidate territory with 1.0.0-rc.0, a milestone that matters because it moves the Rust networking stack from fast-moving experimentation toward something builders can depend on. After roughly four years of development and more than 50 release iterations, the project’s maintainers said the public API was finally close enough to stable for downstream code to build against with confidence. For anyone wiring up peer-to-peer links or direct device-to-device connections without assembling a custom stack from scratch, that is the kind of inflection point that changes whether a project feels promising or practical.

The release did more than stamp a version number on the repo. The maintainers cleaned up the API surface, removed most of the pre-1.0 type re-exports, and split the original PathWatcher into two clearer pieces: Connection::paths() for a snapshot of current paths and Connection::path_events() for a stream of changes. They also pushed optional capabilities into separate crates, moving DhtAddressLookup into iroh-mainline-address-lookup, MdnsAddressLookup into iroh-mdns-address-lookup, and AccessLimit into iroh-util. That modular split lowers pressure on the core stack and gives the ecosystem a cleaner path toward 1.0. Even noq, the QUIC implementation iroh uses, is now on a 1.0 candidate track so it can stabilize alongside the rest of the system instead of lagging behind as a moving target.

The road to rc.0 had already been mapped out in public. In a roadmap published on October 28, 2024, the maintainers committed to shipping iroh 1.0 in the second half of 2025, said the network had seen about half a million unique nodes in a 30-day span, and said they knew of at least 40 projects building on iroh. The project later shifted into a canary series with v0.90 on June 27, 2025, reserving stability for the 1.0 line. Two 2026 releases showed how much transport work sat underneath that promise: 0.96.0, released on January 27, added QUIC multipath and QUIC-NAT-Traversal, while 0.98.0, released April 17, focused on restoring NAT traversal reliability after regressions and expanded the patchbay test matrix to reproduce failing network cases.

That technical groundwork is already showing up downstream. sendme, the file and directory transfer app built on iroh, has updated to iroh@1.0.0-rc.0, a strong signal that other Rust projects now see this as a serious target rather than a preview to ignore. With direct connections whenever possible and relay fallback when needed, plus encrypted end-to-end QUIC transport, iroh’s value still depends on ordinary networks cooperating. This release says the stack is finally mature enough to make that bet at 1.0.