#windows #runtime #com #winrt #uwp


Automatically generated, (mostly) safe bindings for the Windows Runtime APIs

8 releases (5 breaking)

0.5.1 Sep 10, 2018
0.5.0 Mar 30, 2018
0.4.0 Dec 27, 2017
0.3.0 Jul 21, 2017
0.0.1 May 20, 2015

#4 in Windows APIs

Download history 97/week @ 2018-12-19 14/week @ 2018-12-26 10/week @ 2019-01-02 13/week @ 2019-01-09 14/week @ 2019-01-16 9/week @ 2019-01-23 19/week @ 2019-01-30 19/week @ 2019-02-06 6/week @ 2019-02-13 12/week @ 2019-02-20 32/week @ 2019-02-27 139/week @ 2019-03-06 16/week @ 2019-03-13 65/week @ 2019-03-20 11/week @ 2019-03-27

172 downloads per month
Used in 5 crates (2 directly)


236K SLoC

winrt-rust crates.io docs.rs

This crate provides type and method definitions to use the Windows Runtime (WinRT) APIs from Rust.


This library is still subject to breaking changes, but it is already possible to use all APIs, including asynchronous ones (a completion handler can be passed as a closure). Creating custom WinRT classes using inheritance is not yet supported, so it is currently not possible to create user interfaces using XAML.


Using this crate requires at least Rust 1.20. A compatibility mode that requires only Rust 1.15 can be enabled with the lang-compat Cargo feature. Additional nightly features (e.g. using specialization) can be enabled with the nightly Cargo feature.


All definitions are automatically generated from WinMD metadata files. The module structure of the generated code reflects the namespace structure of the original definitions starting at winrt::windows (if the crate has not been renamed on import) for the Windows namespace.

All names have been adjusted to fit the Rust coding style, therefore module names are all in lower case and function names are converted to snake_case.

Since it takes a long time to compile all generated definitions (the generated files amount to more than 15 MB), Cargo features have been introduced that correspond to the WinMD files. For example, to use the definitions from Windows.Devices.winmd, use the feature windows-devices. There is no feature for definitions from Windows.Foundation.winmd, these are always available. Whenever a (method) definition references a type from a different WinMD file, it is also not available until you enable the corresponding features for all required type definitions.

With only the definitions from Windows.Foundation, this crates takes about 10 seconds to compile. With all features enabled (there is a shortcut feature all), compilation can take as long as 5 minutes, so it is highly recommended to enable features only as you need them.


extern crate winrt;

use winrt::*; // import various helper types
use winrt::windows::system::diagnostics::*; // import namespace Windows.System.Diagnostics

fn main() {
    let rt = RuntimeContext::init(); // initialize the Windows Runtime
    let infos = ProcessDiagnosticInfo::get_for_processes().unwrap().unwrap();
    println!("Currently executed processes ({}):", infos.get_size().unwrap());
    for p in &infos {
        let p = p.unwrap();
        let pid = p.get_process_id().unwrap();
        let exe = p.get_executable_file_name().unwrap();
        println!("[{}] {}", pid, exe);

Because this example uses the Windows.System namespace, we have to enable the windows-system feature in Cargo.toml:

version = "0.5.0"
features = ["windows-system"]

Running this example program should result in an output similar to the following:

Currently executed processes (132):
[4] System
[392] smss.exe
[520] csrss.exe
[604] wininit.exe
[612] csrss.exe
[708] winlogon.exe

WinRT and UWP

The Windows Runtime (WinRT) has been introduced in Windows 8 and provides the foundation for building Windows apps that run on different devices using different programming languages. The Universal Windows Platform (UWP) is an extension of WinRT, introduced in Windows 10, that allows using additional, more platform-specific APIs besides those provided by WinRT (according to MSDN). WinRT is not to be confused with the discontinued flavor of the Windows operating system for ARM devices, Windows RT.


Version 0.5.0 (2018-03-30)

  • [Breaking] Wrappers are no longer marked as unsafe 🎉
  • [Breaking] Wrappers for methods that could return null will now return Result<Option<ComPtr<...>>> instead of Result<ComPtr<...>>.
  • [Breaking] Various improvements to how iterators are handled

Version 0.4.0 (2017-12-27)

  • [Breaking] Upgrade to winapi 0.3
  • [Breaking] Default constructors are now accessible via RtDefaultConstructible trait
  • [Breaking] Fixed and improved error handling (among other changes, blocking_get() now returns Result)
  • [Breaking] Output array parameters are now passed as mutable slices (&mut [T])
  • Provide access to IMemoryBufferByteAccess
  • Add another example (hexdump)

Version 0.3.0 (2017-07-21)

  • [Breaking] The self parameter for interface calls is now passed as &self instead of &mut self
  • [Breaking] Remove (empty) contract structs from generated code
  • Documentation improvements

Version 0.2.1 (2017-04-01)

  • Add blocking_get() for async operations
  • Add toast notification example

Version 0.2.0 (2017-03-10)

  • Factories and statics now actually work
  • [Breaking] Feature names use dash instead of underscore

Version 0.1.0 (2016-09-28)

  • First release


Licensed under either of

at your option.


Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.


  • winapi 0.3+winnt+combaseapi+oleauto+roapi+roerrorapi+hstring+winstring+winerror+restrictederrorinfo