Xmake Rust

Building Rust with Xmake

Xmake builds Rust projects via rustc (and optionally cargo for dependency resolution). It gives you the same declarative target() / add_files() model you use for C/C++, plus special support for Cargo package integration and C↔Rust FFI.

1. Minimal project

xmake create -l rust -t console hello
cd hello
xmake run

Generated xmake.lua:

add_rules("mode.debug", "mode.release")

target("hello")
    set_kind("binary")
    add_files("src/main.rs")

That's it — same shape as C++, just .rs files.

2. Target kinds

target("app")       set_kind("binary")      -- executable
target("mylib")     set_kind("static")      -- .rlib / .a
target("mydyn")     set_kind("shared")      -- cdylib

3. Editions / flags

target("app")
    set_kind("binary")
    add_files("src/main.rs")
    set_values("rust.edition", "2021")       -- or "2018", "2015", "2024"
    add_rcflags("-C", "opt-level=3", {force = true})

add_rcflags is the Rust equivalent of add_cxflags. {force = true} bypasses the flag auto-filter.

4. Cargo dependencies — the quick way

For a handful of crates, use cargo::name version in add_requires:

add_requires("cargo::base64 0.13.0")
add_requires("cargo::serde 1.0", {configs = {features = {"derive"}}})

target("app")
    set_kind("binary")
    add_files("src/main.rs")
    add_packages("cargo::base64", "cargo::serde")

Downside: if two of your direct deps share a transitive dep at different versions, you hit "multiple versions of crate" errors. For non-trivial dep trees, use the full-Cargo.toml path below.

5. Cargo dependencies — the full Cargo.toml way

Write a normal Cargo.toml next to your xmake.lua, then let xmake read it:

add_requires("cargo::deps", {configs = {cargo_toml = path.join(os.projectdir(), "Cargo.toml")}})

target("app")
    set_kind("binary")
    add_files("src/main.rs")
    add_packages("cargo::deps")

Cargo resolves the full graph (including transitives) once, xmake consumes the result. Use this for any project with more than a couple of crates.

6. Rust ↔ C++ interop

Call Rust from C++ (cxxbridge)

add_requires("cargo::cxx 1.0")

target("bridge")
    set_kind("static")
    add_files("src/lib.rs")
    add_packages("cargo::cxx")

target("app")
    set_kind("binary")
    add_files("src/main.cpp")
    add_deps("bridge")

Use #[cxx::bridge] in src/lib.rs as with a normal cxx project. Xmake wires up the header generation.

Call C++ from Rust

target("cxxlib")
    set_kind("static")
    add_files("src/cxx/*.cpp")

target("app")
    set_kind("binary")
    add_files("src/main.rs")
    add_deps("cxxlib")

Rust links cxxlib as a native static library via -l. Use extern "C" on the C++ side, extern "C" { ... } block on the Rust side.

Full examples: tests/projects/rust/cxx_call_rust_library and rust_call_cxx_library.

7. Toolchain

xmake f --toolchain=rust                       # force rustc as the toolchain
xmake show -l toolchains                       # see what else is available

Xmake auto-detects rustc on PATH. Pin a specific install via --sdk:

xmake f --toolchain=rust --sdk=$HOME/.rustup/toolchains/stable-x86_64-apple-darwin

8. Cross-compile

xmake f -p windows -a x86_64 --toolchain=rust
xmake

Under the hood xmake passes --target=x86_64-pc-windows-msvc (or equivalent) to rustc. The corresponding Rust target component must be installed:

rustup target add x86_64-pc-windows-msvc

9. Running tests

xmake run app --some-arg

Or add test cases:

target("app_test")
    set_kind("binary")
    add_files("tests/*.rs")
    add_tests("default")

See xmake-tests.

Pitfalls

• Multiple crate versions. cargo::foo + transitive cargo::foo at a different version → link errors. Switch to the full Cargo.toml route.
• Missing rustup target add. Cross-compile fails with "can't find crate for std". Install the Rust target component first.
• set_languages("..."). Doesn't apply to Rust — use set_values("rust.edition", "2021").
• Mixing cargo:: and manual -l flags. Let add_packages("cargo::...") own the link line; mixing hand-rolled add_links gets messy.
• .rs and .cpp in the same target. Not supported — split into two targets with add_deps.

When to branch out

• Build modes / debug vs release → xmake-targets, xmake-build-optimization
• Cross-compile plumbing → xmake-cross-compilation
• Package management concepts → xmake-packages
• Testing → xmake-tests