ort 2.0.0-rc.14 requires an explicit ONNX Runtime environment

ort 2.0.0-rc.14, the Rust binding for ONNX Runtime published by pyke, went out on 12 October 2026 at 20:34 UTC. The previous tag, v2.0.0-rc.13, was published on 28 July 2026 at 08:13 UTC, about two and a half months earlier. This is still a release candidate. On crates.io, 2.0.0-rc.14 is the newest version. ort is a community wrapper. The Cargo.toml names the authors as pyke.io and Nicolas Bigaouette, and it describes the crate as a wrapper for ONNX Runtime 1.31. It is not a Microsoft product. This piece does not include a local build.

The crates.io API, fetched at 05:38 UTC on 13 October, reported 21,755,077 total downloads for the ort crate and 8,413,966 in the API’s recent-downloads field. Version 2.0.0-rc.14 itself had 239 downloads. The license line in that manifest is MIT OR Apache-2.0. The rust-version field is 1.92, matching the release notes’ MSRV bump.

The environment is no longer global

The notes replace the global ort::init().commit() pattern. You create an Environment and pass it to Session::builder. The sample below is the one in the release notes:

// pre-rc.14
{
    // optional, even!
    ort::init().commit()?;

    let mut model = Session::builder()?
        .with_optimization_level(GraphOptimizationLevel::Level3)?
        .with_intra_threads(4)?
        .commit_from_file("yolov8m.onnx")?;
}

// rc.14
{
    let env = ort::init().build()?; // <-- must build an environment first
    let mut model = Session::builder(&env)?
        .with_optimization_level(GraphOptimizationLevel::Level3)?
        .with_intra_threads(4)?
        .commit_from_file("yolov8m.onnx")?;
}

The notes say you do not have to keep env unless you will create more sessions. They also say not to store environments or sessions as global variables, because the project cannot fix the issues that causes inside ONNX Runtime. Library authors are told to let callers pass their own Environment. There is no separate migration page: ort.pyke.io/migration answered 404 on 13 October. The notes are the upgrade text.

Rust 1.100 and copy-dylibs

The notes add support for the upcoming v2 build-dir layout, linking Cargo pull request 17354, which they say will ship in Rust 1.100. releases.rs lists 1.100.0 as unreleased and says it will be stable on 12 November 2026. That date is the schedule on that page.

The failure mode is qualified. The notes say older ort versions will fail to build when copy-dylibs is enabled, and that anyone who intends to update to Rust 1.100 should move to rc.14. copy-dylibs is a default feature. The cargo-features page, last updated 28 July 2026, marks it “enabled by default,” and the rc.14 manifest’s default list still includes copy-dylibs along with std, ndarray, tracing, download-binaries, tls-native and api-31. That docs page was not rewritten for rc.14. The manifest was.

Under the new layout, the notes say, tests can no longer see dylibs copied by copy-dylibs. They suggest trying ort::util::preload_dylib to set the path to provider dylibs by hand.

Binaries, other breaks, and a checklist

The new prebuilt binaries, as the notes list them: CUDA builds add RTX 50xx and Blackwell on x64, and aarch64 builds for Jetson Orin and Thor, Grace Hopper and Blackwell, and DGX Spark. Turing and Ampere stay supported, the notes say. MIGraphX binaries are on x64 Linux. OpenVINO builds are for Windows and Linux x64. x64 Android binaries were added. Windows builds with the Vitis AI execution provider, for Ryzen AI NPUs, are described as future work, not as something rc.14 ships.

Also in the notes: ONNX Runtime 1.31.0, with ort-web at 1.30.0; ort::util::probe on the load-dynamic feature, to check the ONNX Runtime version before loading it; removal of get_ and set_gpu_device; an execution-provider refactor in which ep.name() becomes EP::name() and ep.is_available() becomes EP::is_available(); and a preload_dylibs update for CUDA 13. The memory-safety lines are a double-free fix in run_async, a memory leak in Session::overridable_initializers(), and memory-leak and use-after-free fixes in Trainer. Those are the project’s descriptions of its patches.

For a crate that depends on ort:

1. Build an environment with ort::init().build()? and pass &env to Session::builder. Drop ort::init().commit() and Session::builder() with no environment.
2. If you publish a library, take the caller’s Environment. Do not store environments or sessions as globals.
3. If you will compile on Rust 1.100, move to rc.14 while copy-dylibs remains enabled. That feature is on by default.
4. In tests, the copied dylibs may be invisible under the v2 build directory. The notes point at ort::util::preload_dylib.
5. Remove calls to get_gpu_device and set_gpu_device. If you call execution providers through the old methods, switch to EP::name() and EP::is_available().
6. Treat rc.14 as a candidate. crates.io does not list a 2.0.0 stable release above it.