An introduction to the build pipeline, and how we can orchestrate it manually

Before working with CMake, it's useful to understand the tools it orchestrates. This lesson guides you through setting up a C++ toolchain.

Building C++ Programs

Walking through the steps of the C++ compilation process, from source code to machine code.

The Compilation Pipeline

The linker's role in the build process, how it resolves symbols to combine object files, and how to troubleshoot common errors.

Object Files and the Linking Process

The difference between static and dynamic libraries, how to create them, and the trade-offs between them.

Static and Shared Libraries

The C++ Build Process

Recommended approaches for managing large projects and the libraries that they depend on

Learn how to structure your C++ projects for scalability and maintainability, from basic directory layouts to managing multiple modules.

Organizing a C++ Project

Learn to manage third-party libraries in C++, covering include/library paths, static vs. shared libraries, versioning, and platform differences.

Managing Libraries and Dependencies

An introduction to traditional build tools like Makefiles and IDE projects, highlighting the maintenance, scalability, and cross-platform challenges that result

Automated Build Systems and Their Limitations

Project Structure and Dependency Management

Setting up CMake and creating your first project

An introduction to CMake, the cross-platform, open-source meta-build system that solves the core challenges of C++ project management.

Why CMake?

A step-by-step guide to installing CMake. We'll explore command-line, GUI, and IDE workflows, and how to configure your compiler.

Setting Up a CMake Environment

Creating the bare minimum `CMakeLists.txt` file and build up to a project with an executable and a library, learning the fundamental commands along the way.

Writing a CMakeLists File

Learn the two-stage process of building a CMake project. This lesson covers configuring, generating, building, running, and troubleshooting common errors.

Building and Running CMake Projects

Learn how to organize large C++ projects in CMake using subdirectories and the `add_subdirectory()` command to create modular, maintainable builds.

CMake Project Structure and Subdirectories

Introducing CMake

Exploring CMake's programming features, caching mechanisms, and interactions with the file system

A primer on the fundamental building blocks of the CMake language: variables, string interpolation, and logging messages.

CMake Variables and Logging

Discover the CMake Cache, the mechanism for storing persistent user-configurable options, and learn how to create and manage cached variables.

The CMake Cache

Exploring CMake's command syntax and its list data type, including how to create, manipulate, and use lists in your projects.

CMake Commands, Arguments, and Lists

Transform your static build descriptions into dynamic scripts with CMake's control flow commands, if() and foreach().

CMake Conditionals and Loops

Exploring CMake's `file()` command, covering how to read, write, copy, and glob files, and how to manipulate paths.

Working with the File System

Learn to create reusable logic with CMake functions and macros, and how to organize them into modules for clean, scalable build systems.

Modularizing CMake Code

CMake Language and Fundamentals

Learn more about targets, and how their properties and links are the foundation of modern CMake

Learn to work with target properties - understanding their purpose, setting and updating them, and retrieving them when your build requires it

Target Properties

Learn about target types, and how the `PUBLIC`, `PRIVATE`, and `INTERFACE` keywords control how properties are shared.

Relationships Between Targets

Discover how CMake's `target_link_libraries()` command builds a dependency graph, and how it uses this graph to automatically manage transitive dependencies and link order.

Indirect Relationships and the Dependency Graph

Learn to use abstract target types like `INTERFACE`, `ALIAS`, and `IMPORTED` to model complex project needs, organize build properties, and integrate pre-compiled binaries.

Using `INTERFACE`, `ALIAS`, and `IMPORTED` Libraries

Adding support for user-configurable library types and an initial introduction to target installation.

Using Shared Libraries

Targets and Dependencies

Learn how to manage multiple build configurations within the same project, and how to create scripts that adapt to the environment

Learn how CMake manages different build configurations like Debug and Release, the difference between generator types, and how to apply settings conditionally using modern techniques.

Build Configurations (Debug, Release, etc.)

Learn the tools and patterns needed to write portable CMakeLists.txt files that work seamlessly across platforms and compilers

Cross-Platform Configurations

Learn to write architecture-aware CMake scripts for 32/64-bit systems and Apple's Universal Binaries (Intel/ARM).

Handling Different Architectures

Learn to build for different operating systems and architectures using CMake's cross-compilation support and toolchain files.

Cross-Compilation and Toolchain Files

Platforms and Build Configurations

Learn how to add external libraries to our build, and how to create our own packages for others to use

Learn to find and use pre-installed libraries with `find_package()`, understanding Module vs. Config mode and the power of imported targets

Finding Dependencies using `find_package()`

Learn how to make your libraries consumable by other projects using CMake by turning your build-tree into a distributable install-tree.

Creating a Consumable Package

Learn how to consume a CMake package you've installed, completing the producer-consumer cycle. We'll cover using `find_package()` and how to point CMake to your library's location

Using Installed Packages

Learn how to create self-contained, reproducible builds by fetching dependencies from source using `FetchContent()` and `ExternalProject_Add()`.

Fetching External Dependencies

Creating and Consuming Packages

Integrating the vcpkg and Conan package managers to handle external dependencies

Learn to manage C++ dependencies effortlessly with the vcpkg package manager and its seamless CMake integration using toolchain files and manifests.

Integrating CMake and vcpkg

Learn the day-to-day commands for managing dependencies with vcpkg and how to guarantee reproducible builds using baselines and version overrides

vcpkg Commands and Versioning

Combine vcpkg with CMake's cross-compilation capabilities. Learn to use triplets to target different architectures and chain-load toolchain files

Cross-Compiling with vcpkg

Discover Conan, the binary-first C++ package manager, and learn how to integrate it with CMake using profiles and lockfiles for fast, reproducible builds.

Using Conan with CMake

Learn to cross-compile C++ projects with Conan, using build and host profiles to manage dependencies for different platforms.

Cross-Compilation with Conan

Package Managers

Introducing presets, allowing us to simplify our workflow and share common configurations across our team

Learn the fundamentals of CMake Presets. This lesson introduces `CMakePresets.json` to simplify complex build commands.

CMake Presets

Learn to structure your CMake presets with inheritance and customize them for your local environment using `CMakeUserPresets.json`.

User Presets and Inheritance

Learn to make your CMake presets portable by using environment variables and conditional logic to adapt to different machine configurations.

Environment Variables and Conditional Presets

Learn how to extend the build process beyond simple compilation by integrating external tools and custom commands

Learn how to use generator expressions `$<...>` for build-time conditional logic.

Generator Expressions and Conditional Logic

Learn how to attach commands to specific points in a target's build lifecycle using `add_custom_command(TARGET)` for tasks like post-build file copying.

Integrating Tools with `add_custom_command()`

Learn to integrate code generators like Protobuf into your build process using `add_custom_command()`, creating automated file-level dependencies in CMake.

Generating Files with Protobuf and `add_custom_command()`

Custom Commands

An introduction to automating common workflow chores by creating custom targets

Learn to create standalone, non-code targets using add_custom_target() for utility tasks like code formatting and documentation generation.

Custom Targets and Build Utilities

Using the Clang-Format tool to automatically enforce a consistent coding style, and integrating it into our build using a custom CMake target

Using Clang-Format

An introduction to file sets and the `target_sources()` command, allowing us to manage our header files in a more controlled way

Using File Sets

A step-by-step guide to integrating Doxygen into your CMake build process for automated C++ documentation.

Generating Documentation with Doxygen

Custom Targets

Integrate automated tests into a CMake project using CTest, GoogleTest, and GoogleMock

Learn the fundamentals of automated testing in C++ with CTest. Create your first test suite, register tests with `add_test()`, and run them with the `ctest` command.

Automated Testing and CTest

Learn to refactor manual C++ tests into a professional test suite using the GoogleTest framework, managed by vcpkg and integrated with CTest.

Integrating GoogleTest with CMake

Learn to use a wide range of assertions, write data-driven parameterized tests, and isolate dependencies with Google Mock.

Assertions and Parameterized Tests

Learn how to isolate dependencies that our project uses, and then how to replace those dependencies at test time using Google Mock.

Dependency Injection and Mocking

Learn the standard pattern for testing application logic by refactoring it into a linkable library

Testing Executables

Move beyond individual tests to manage a full test suite. Learn to organize tests, run tests in parallel, filter by labels, and measure our code coverage

Managing a Test Suite

Automated Testing

Using static and dynamic analysis in CMake projects to automatically detect memory bugs, performance issues, and problematic code

Learn to find memory bugs at runtime by integrating AddressSanitizer (ASan) into a CMake project

Using AddressSanitizer (ASan)

Adding benchmarks to our build to measure the performance of our code, and track how it changes over time

Using Google Benchmark

Integrating Clang-Tidy to enforce good practices and find bugs before we even compile

Using Clang-Tidy

Automated Analysis

Automating the entire development lifecycle using Git for souce control, GitHub Actions for cloud builds, and CPack to create distributable packages and installers.

An introduction to Git, the version control system that underpins modern collaborative software development and automated build pipelines.

Source Control with Git

Learn how to automate your build and test process with Continuous Integration (CI) and a build server. This lesson provides a guide to creating a GitHub Actions workflow for a CMake project.

Build Servers and Continuous Integration

Learn to package your C++ projects using CMake's CPack. This lesson covers creating developer ZIP archives and professional Windows MSI installers with components.

Packaging with CPack

Learn to automate the packaging process by integrating CPack with a multi-platform GitHub Actions workflow

Packaging with GitHub Actions

Learn to automate the creation of a professional Windows installer by integrating CPack, the WiX Toolset, and a multi-platform GitHub Actions workflow.

Creating Installers with CPack and GitHub Actions

Learn to automate the release process using a GitHub Actions workflow that builds, packages, and publishes artifacts to a GitHub Release

Deployment with GitHub Releases

Continuous Integration and Packaging

If you have a basic grasp of C++ but find the build process intimidating, this course is for you. We assume you know the language, but not how to manage large projects.

Manage complex, cross-platform builds using industry-standard tools. Create scalable build systems that automate the entire development lifecycle.

This course is a comprehensive deep-dive into the entire C++ build ecosystem, centered around the power and flexibility of modern CMake. We leave no stone unturned.

Start with a foundational understanding of compilers, linkers, static vs. shared libraries, and object files.

The Full Build Pipeline

Learn every aspect of the CMake language, from variables and control flow to functions, modules, and generator expressions.

Complete CMake Language Mastery

Master the modern target-centric paradigm, including properties, usage requirements, and abstract targets.

Advanced Target Management

Explore every method for handling dependencies, from `find_package` and `FetchContent` to vcpkg and Conan, including versioning and cross-compilation.

In-Depth Dependency Management

Integrate a full suite of professional tools for testing (CTest, GoogleTest), analysis (ASan, Clang-Tidy), and packaging (CPack).

Total Workflow Automation

Build a fully automated deployment pipeline that takes your code from a Git push to a published GitHub Release with multi-platform installers.

End-to-End CI/CD and Deployment

What You'll Learn

Become a software engineer with C++.  Starting from the basics, we guide you step by step along the way

Intro to C++ Programming

If you're completely new to programming or want a thorough introduction, consider starting with our free introductory course:

New to Programming?

Managing C++ Projects Using CMake

In the previous lesson, we did the hard work of turning our `GreeterLib` into a distributable CMake package. We created an "install-tree" containing our compiled library, public headers, and the special `...Config.cmake` files that power the `find_package()` command.


In this lesson, we'll switch hats and become a consumer of our own library. We will modify our `GreeterApp` to find and use the installed version of `GreeterLib`, just as if it were any other third-party dependency like Boost or spdlog.


This will not only verify that our packaging work was successful but also teach you the final, crucial step in the dependency management puzzle: how to tell CMake **where** to look for the packages you've installed.


## Using the `GreeterLib` Package


We should test that anyone interested in our new, sharable library can use it how we expect.  Let's update `GreeterApp` to consume our library in this form, as if it were a third-party dependency.


### Using `find_package()`


First, in our root `CMakeLists.txt`, we'll CMake to try to find an installed `GreeterLib` package before reverting to the build-tree dependency using `add_subdirectory()`:


<CodeFile path="CMakeLists.txt" status="Updated">


```c++
#<cmake>
cmake_minimum_required(VERSION 3.16)

project(Greeter VERSION "1.0")

find_package(GreeterLib)#<h>
if (GreeterLib_FOUND)#<h>
  message(STATUS "Using Installed GreeterLib")#<h>
else()#<h>
  add_subdirectory(greeter)#<h>
endif()#<h>

add_subdirectory(app)
```


</CodeFile>


This approach avoids our testing environment getting stuck in a situation where we can't build our project because we haven't installed our package, and we can't install our package because our project can't be built.


We can tell which version of our library is being used by looking for the warning message generated by `find_package()` when it fails, or the `STATUS` message we added when `GreeterLib_FOUND` is true.


### Updating the Link


Over in `app/CMakeLists.txt`, we'll need to update our `target_link_libraries()` command to use the new `Greeter::Lib` name:


<CodeFile path="app/CMakeLists.txt" status="Updated">


```c++
#<cmake>
cmake_minimum_required(VERSION 3.16)

add_executable(GreeterApp src/main.cpp)

target_link_libraries(GreeterApp GreeterLib) #<d>
target_link_libraries(GreeterApp Greeter::Lib) #<h>
```


</CodeFile>


### Running the Configure Step


The final problem is that CMake doesn't know where our package is.  If we try to configure the project, our `find_package()` command will fail with a warning before falling back to `add_subdirectory()`:


```c++
//<ti>
cmake ..
```


```c++
//<oe>
CMake Warning at CMakeLists.txt:12 (find_package):
By not providing "FindGreeterLib.cmake" in CMAKE_MODULE_PATH this project
  has asked CMake to find a package configuration file provided by
  "GreeterLib", but CMake did not find one.
```


## Helping `find_package()` Find Things


We need to tell `find_package()` where to search, and the error message gives us some hints.


CMake stores the locations where it will search for packages as a list called `CMAKE_PREFIX_PATH`.  We can append our `/install` directory to that list:


<CodeFile path="CMakeLists.txt" status="Updated">


```c++
#<cmake>
cmake_minimum_required(VERSION 3.16)
project(Greeter VERSION "1.0")

list(APPEND CMAKE_PREFIX_PATH "${PROJECT_SOURCE_DIR}/install")#<h>
find_package(GreeterLib)

# ...
```


</CodeFile>


Alternatively, we can provide the specific location of `GreeterLib`'s installed configuration file (`GreeterLibConfig.cmake`) by setting the `GreeterLib_DIR` variable:


<CodeFile path="CMakeLists.txt" status="Updated">


```c++
#<cmake>
cmake_minimum_required(VERSION 3.16)
project(Greeter VERSION "1.0")

set(GreeterLib_DIR#<h>
  "${PROJECT_SOURCE_DIR}/install/lib/cmake/GreeterLib"#<h>
)#<h>

find_package(GreeterLib)

# ...
```


</CodeFile>


If we don't want to update our `CMakeLists.txt` file, we can set cached values using either approach when configuring on the command line:


```c++
//<o>
cmake -DCMAKE_PREFIX_PATH="./install" ..
```


```c++
//<o>
cmake -DGreeterLib_DIR="./install/lib/cmake/GreeterLib" ..
```


Implementing any of these techniques should be enough to let our `find_package()` command finally succeed:


```c++
//<ti>
cmake ..
```


```c++
//<o>
-- Using Installed GreeterLib
```


Success! CMake now finds our `GreeterLibConfig.cmake`, loads the imported `Greeter::Lib` target, and successfully configures the project. We can now build and run `GreeterApp`, and prove that our `GreeterLib` can now also be used as a standalone, sharable package:


```c++
//<ti>
cmake --build .
```


```c++
//<ti>
./app/GreeterApp
```


```c++
//<o>
Hello from the modular greeter library!
```


<Aside>


### Reinstalling


In our current setup, it's a little unclear how we might reinstall our package.  The `add_subdirectory(greeter)` command is not used when the package is already installed and found, meaning CMake won't load our installation instructions in `greeter/CMakeLists.txt`.


We already know a few ways to improve this - for example, we could add an `option()` variable to let users control the behaviour of our script.  We'll also learn some new techniques in the next chapter that will be helpful.


For now, simply deleting the `/install` directory and rerunning the configure, build, and install steps would work:


```c++
//<ti>
cmake ..
cmake --build .
cmake --install . --prefix "../install"
```


</Aside>


<Pw>


## Installing Arbitrary Files


A complete package often includes more than just compiled binaries and public headers. You may want to distribute important supplementary materials like:

- A `LICENSE` file
- A `README` file with usage instructions
- Assets such as images and fonts that the program needs to run

The `install()` command has subcommands specifically for handling these arbitrary files and directories.


### Installing Individual Files


The `install(FILES ...)` command is the most direct way to install one or more specific files. Let's say we add a `LICENSE` file to our project:

<CodeFile path="LICENSE" status="New">


```c++
Permission is hereby granted to...
```


</CodeFile>


We can add an `install()` rule to our `CMakeLists.txt` to place this file in a `share/doc/[ProjectName]` directory within our install-tree. This is a common convention on Unix-like systems.


```c++
#<cmake>
install(FILES "${PROJECT_SOURCE_DIR}/LICENSE"
  DESTINATION "${CMAKE_INSTALL_DATADIR}/doc/${PROJECT_NAME}"
)
```


Here, `${CMAKE_INSTALL_DATADIR}` is another helpful variable from the `GNUInstallDirs` module, which typically resolves to `share`.


### Installing Entire Directories


If you need to install a whole folder of content, such as generated documentation or a set of example projects, `install(DIRECTORY ...)` is the right tool. We've already used it to install our headers:


```c++
#<cmake>
install(DIRECTORY "${PROJECT_SOURCE_DIR}/include/"
  DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}
)
```


This command recursively copies the entire `include` directory to the destination.


You can also be more selective. Imagine you have an `assets` directory that contains both source files (`.png`) and intermediate files (`.psd`) that you don't want to distribute. You can use `PATTERN` to filter what gets copied.


```c++
#<cmake>
# Only install the .png files from the assets directory
install(DIRECTORY "${PROJECT_SOURCE_DIR}/assets/"
  DESTINATION "${CMAKE_INSTALL_DATADIR}/${PROJECT_NAME}/assets"
  FILES_MATCHING
  PATTERN "*.png"
)
```


The trailing slash on `"assets/"` is important. It tells CMake to copy the **contents** of the directory, not the directory itself. Without it, you would get an extra `assets` folder at the destination (e.g., `.../assets/assets/`).


## Summary


In this lesson, we completed the producer-consumer cycle. We learned how to use the package we created in the previous lesson, treating it as a true third-party dependency.

- **Finding Packages**: We used `find_package()` to locate our installed library.
- **Find-or-Build Pattern**: A robust approach is to first try `find_package()` and fall back to `add_subdirectory()` if the installed package isn't found.
- **Helping CMake Find Packages**: We learned the two primary ways to tell `find_package()` where to look: setting the generic `CMAKE_PREFIX_PATH` or the specific `PackageName_DIR` variable, either in the `CMakeLists.txt` or on the command line.
- **Installing Arbitrary Files**: We saw how to use `install(FILES ...)` and `install(DIRECTORY ...)` to include non-target files like documentation and assets in our final installation.

<Preview>


### Fetching Dependencies at Configure Time


Installing dependencies manually and then pointing CMake to them with `CMAKE_PREFIX_PATH` works, but it's a lot of manual steps. What if CMake could just download and build the dependencies for us automatically?


In the next lesson, we will explore CMake's built-in tools for doing just that: `FetchContent` and `ExternalProject_Add`. These commands allow you to pull dependencies directly from sources like the internet as part of your configure or build step.


</Preview>


</Pw>

Fixed missing trailing slash in include directory configuration, and fixed minor grammar issue

Vendoring and Fetching Dependencies

`install()` Command Documentation

CMakePackageConfigHelpers Module

Creating Packages

It's Time To Do CMake Right - Exporting and Installing

Everything you need to know about installing and reusing CMake projects

How to create a CMake export configuration?

Property Groups, Aliases, and Imports

This step-by-step CMake tutorial shows you how to use a library you've installed. Learn to use `find_package()` to locate your package, how to configure search paths with `CMAKE_PREFIX_PATH`, and how to link against the imported targets.

Using Installed Packages

Understanding the Basics

Practical Applications

Common Mistakes

Next Steps

Additional Resources

Assessment Preparation

Managing C++ Projects Using CMake