Clue - A C++ Build System

A C++ build system written in Go using CUE for configuration. Clue provides minimal configuration for common cases, with CUE's type system catching config errors before build time.

Installation

Install from source:

go install github.com/loov/clue@latest

Or build locally for development:

go build -o clue .

Quick Start

Create a clue.cue file in your project directory:

name: "hello"
version: "1.0.0"
toolchain: {
    compiler: "clang"
    std:      "c++17"
}
targets: {
    hello: {
        name:    "hello"
        type:    "executable"
        sources: ["main.cpp"]
    }
}

Validate and build:

clue validate    # Check configuration
clue build       # Build project

Commands

• clue validate - Validate configuration and check dependencies
• clue build - Build all targets (use -variant release for optimized builds)
• clue clean - Remove build artifacts (use -all to clean all variants)
• clue run <target> - Build and run an executable target
• clue deps <list|fetch|clean|update> - Manage external dependencies
• clue generate <ninja|compile-commands|all> - Generate build files for editors/tools

Common Flags

• -variant debug|release - Select build variant (default: debug)
• -j N - Number of parallel jobs (0 = half CPU cores, -1 = all cores)
• -v - Verbose output showing detailed build steps
• -quiet - Suppress all non-error output
• -rebuild-all - Force rebuild of all files
• -keep-going - Continue building despite errors
• -target <platform> - Cross-compile for target platform (e.g., linux-arm64, darwin-amd64)

Example Configurations

Multi-target project with library

name: "calculator"
version: "1.0.0"
toolchain: {
    compiler: "clang"
    std:      "c++17"
}
targets: {
    mathlib: {
        name:    "mathlib"
        type:    "static_library"
        sources: ["lib/math.cpp"]
        headers: ["lib/math.h"]
    }
    app: {
        name:     "calculator"
        type:     "executable"
        sources:  ["src/main.cpp"]
        includes: ["lib"]
        depends:  ["mathlib"]
    }
}

Build variants

variants: {
    debug: {
        optimization: "none"
        debugInfo:    true
    }
    release: {
        optimization: "aggressive"
        debugInfo:    false
    }
}

Build with a variant:

clue build -variant release