Nimbus: A Modern C++ Build System and Package Manager

Nimbus is a lightweight and modern C++ build system and package manager designed to streamline your C++ development workflow. With a simple command-line interface, easy configuration through nimbus.toml, and intelligent handling of build options, Nimbus helps you focus on writing code rather than wrestling with build files.

Features

• Initialize New Projects: Quickly set up a new C++ project with sensible defaults using nimbus init. It automatically creates a source and include directory, generates a nimbus.toml configuration file.

• Build with Ease: Compile your project using nimbus build. Nimbus leverages your compiler of choice and the settings defined in nimbus.toml to create an optimized or debug-friendly binary, depending on your specified build type.

• Intelligent Build Types: Select from various build types such as Debug, Release, RelWithDebInfo, or MinSizeRel. Nimbus automatically applies the corresponding compiler flags and preprocessor macros (e.g., DEBUG, RELEASE, RELWITHDEBINFO, MINSIZEREL) at compile time, enabling or disabling certain debugging features, optimization levels, or size-reduction strategies as needed.

• Flexible Configuration: Control your project’s compiler, standard, and build type directly from nimbus.toml. Easily tweak settings without touching build scripts, thanks to an intuitive TOML-based configuration.

Getting Started

1. Installation (Ensure you have a clang++/g++ supporting modules, as well as toml11 and CLI11 on your machine):

   git clone https://github.com/nimbus-cpp/nimbus.git
   cd nimbus
   mkdir build && cd build
   
   # init module
   clang++ -std=c++20 ../src/commands/init.cppm --precompile -o init.pcm -I/path/to/includes/CLI11+toml11
   clang++ -std=c++20 ../src/commands/init.cppm -c -o init.o -I/path/to/includes/CLI11+toml11
   
   # build module
   clang++ -std=c++20 ../src/commands/build.cppm --precompile -o build.pcm -I/path/to/includes/CLI11+toml11
   clang++ -std=c++20 ../src/commands/build.cppm -c -o build.o -I/path/to/includes/CLI11+toml11
   
   # main
   clang++ -std=c++20 ../src/main.cpp -fprebuilt-module-path=. init.o build.o -o nimbus -I/path/to/includes/CLI11+toml11

2. Project initialization:

   To initialize the current directory as a nimbus project (which will use the dir name as the name of the project in the generated nimbus.toml):

   nimbus init

   To create a new project from scratch:

   nimbus init my_project

   This sets up a basic directory structure:

   my_project/
   ├─ include/
   ├─ src/
   └─ nimbus.toml

   Inside nimbus.toml, you'll find default values for your project's name, version, authors, and build configuration:

   [project]
   name = "my_project"
   version = "0.1.0"
   authors = ["Your Name <you@example.com>"]
   
   [build]
   compiler = "clang++"
   standard = "c++20"
   build_type = "Debug"

   Adjust these as needed. For example, changing build_type from "Debug" to "Release" switches your project from including debugging symbols and DEBUG macro to producing an optimized binary with the RELEASE preprocessing macro.

3. Building the project:

   Once your project is initialized and configured, running:

   nimbus build

   Will:

   • Create the build directory if it doesn’t exist.
   • Read configuration options from nimbus.toml.
   • Compile all .cpp, .c, or .cxx files in src/ using the specified compiler and flags.
   • Apply the appropriate preprocessor definitions based on the selected build type.
   • Generate the output binary in build/, naming it using the name config from nimbus.toml.

   Supported build_type values and their generated preprocessor macros(available to use in-code):

   • Debug -> DEBUG
   • Release -> RELEASE
   • RelWithDebInfo -> RELWITHDEBINFO
   • MinSizeRel -> MINSIZEREL

   #include <iostream>
   
   int main() {
   #ifdef DEBUG
     std::cout << "Build Mode: Debug\n";
   #elif defined(RELEASE)
     std::cout << "Build Mode: Release\n";
   #elif defined(RELWITHDEBINFO)
     std::cout << "Build Mode: RelWithDebInfo\n";
   #elif defined(MINSIZEREL)
     std::cout << "Build Mode: MinSizeRel\n";
   #else
     std::cout << "Build Mode: Unknown\n";
   #endif
     return 0;
   }