cargo-crossbuild is a production-grade Rust cross-compilation platform for building crates across Windows, Linux, and macOS without Docker or virtual machines. It automatically discovers installed toolchains, linkers, and sysroots to produce correct cross-compilation configurations.

• Multi-platform targets — Build for any Rust target triple from any host
• Automatic provider resolution — Discovers rustup, Zig, MSVC, GCC, Clang, LLD, and Mold toolchains
• Native MSVC detection — Finds Visual Studio's link.exe on Windows automatically
• Zig cross-compilation — Uses Zig's C frontend as a drop-in cross-compiler
• Cargo config generation — Writes .cargo/config.toml with correct linker and target settings
• Dry-run planning — Preview the build plan without executing it
• Cache management — LRU eviction, expiry, and compression for downloaded toolchains and sysroots
• Lockfile support — Reproducible builds with configuration hashing and verification
• Provider registry — Pluggable provider architecture for custom toolchain/sysroot/linker backends

The workspace is organized into 24 crates with a narrow CLI frontend and a shared core library:

# List available subcommands
cargo crossbuild --help

# Build for a specific target
cargo crossbuild build --target aarch64-unknown-linux-gnu

# Dry-run to preview the build plan without executing
cargo crossbuild build --dry-run --target x86_64-pc-windows-msvc

# Run system diagnostics
cargo crossbuild doctor

# List known target triples
cargo crossbuild list-targets

# Clean build artifacts and cache
cargo crossbuild clean

Usage: cargo-crossbuild build [OPTIONS] --target <TARGET> [CARGO_ARGS]...

Arguments:
  [CARGO_ARGS]...  Extra arguments passed through to cargo

Options:
  -t, --target <TARGET>          Target triple (e.g. x86_64-unknown-linux-gnu)
  -m, --manifest-path <PATH>     Path to Cargo.toml [default: ./Cargo.toml]
      --dry-run                  Plan the build without executing it
      --release                  Build in release mode
      --features <FEATURES>      Comma-separated list of features
      --no-default-features      Do not include default features
      --workspace                Build the entire workspace
  -v, --verbose                  Verbose output
      --profile <PROFILE>        Build profile name
      --exclude <PACKAGE>...     Packages to exclude (for workspace builds)

1. Request — CLI parses the target triple and build options into a BuildRequest
2. Discovery — Platform detection identifies the host triple, architecture, and OS
3. Provider Resolution — The provider registry iterates through toolchain, sysroot, and linker providers by priority, selecting the first that can_provide() for the target
4. Planning — The planner constructs a BuildPlan with command line, cargo config, environment variables, and execution steps
5. Execution — The runner executes cargo with the configured environment and linker, capturing output and reporting diagnostics

Production-ready architecture with a working build pipeline. All 24 crates compile and pass tests.