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

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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:

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Managing C++ Projects Using CMake

In the <InlineLessonPromo url="cmake/cmake-presets" title="CMake Presets" description="Learn the fundamentals of CMake Presets. This lesson introduces `CMakePresets.json` to simplify complex build commands.">previous lesson</InlineLessonPromo>, we took our first step into the world of CMake Presets. We saw how a `CMakePresets.json` file can transform a long, cumbersome command line into a single, memorable name, making our build workflows easier to use and share.


This is a great start, but as a project grows, so does its configuration complexity. You'll need presets for different operating systems, compilers, build types, and architectures. A simple, flat list of presets quickly becomes a repetitive, unmaintainable mess. Furthermore, how do you handle a developer's personal preferences without cluttering the shared, team-wide configuration?


This lesson builds on the fundamentals by introducing two powerful concepts: **user presets** for personal customization and **inheritance** for creating a scalable, layered preset architecture.


As a reminder, the example `CMakePresets.json` from the previous lesson is provided below:


<CodeFile path="CMakePresets.json">


```json
{
  "version": 3,
  "configurePresets": [{
    "name": "windows-x64-debug",
    "displayName": "Windows x64 Debug",
    "description": "Build for 64-bit Windows with MinGW (Debug)",
    "binaryDir": "${sourceDir}/build/windows-x64-debug",
    "cacheVariables": {
      "CMAKE_BUILD_TYPE": "Debug",
      "CMAKE_TOOLCHAIN_FILE":
        "${sourceDir}/toolchains/mingw-windows-x64.cmake"
    }
  }],
  "buildPresets": [{
    "name": "windows-x64-debug",
    "configurePreset": "windows-x64-debug",
    "displayName": "Build Windows x64 (Debug)"
  }]
}
```


</CodeFile>


## User Presets


This system works perfectly, but what if a developer on the team wants to create a preset that isn't likely to be useful to the wider team?


Or what if they have a personal preference that doesn't match what is in the shared presets that everyone else is using? Maybe they want to use a different generator, or they want to output the build in a different directory.


This is solved by a CMake recognizing **two** different preset files:

1. `CMakePresets.json`: This file is for **shared, team-wide configurations**. It should be maintained and shared across the whole team and checked into your version control system (like Git, which we cover later). It defines the canonical ways to build your project that should work for everyone.
2. `CMakeUserPresets.json`: This file is for **personal, machine-specific presets**. Each developer can create their own to customize the build for their local environment.

### A Practical Example


Let's imagine we prefer our build outputs to be placed in an `/output` directory instead of `/build`. This is just a personal preference - not something we want to force on the entire team. To implement this, we'd create a `CMakeUserPresets.json` file, and set up our values just like we did in the shared `CMakePresets.json`. For example:


<CodeFile path="CMakeUserPresets.json" status="New">


```json
{
  "version": 3,
  "configurePresets": [{
    "name": "windows-x64-debug-out",
    "displayName": "Windows x64 Debug (Out)",
    "description": "Build for 64-bit Windows with MinGW (Debug)",
    "binaryDir": "${sourceDir}/out/windows-x64-debug",
    "cacheVariables": {
      "CMAKE_BUILD_TYPE": "Debug",
      "CMAKE_TOOLCHAIN_FILE":
        "${sourceDir}/toolchains/mingw-windows-x64.cmake"
    }
  }]
}
```


</CodeFile>


Now, when we list our presets, we will see both the shared and personal preset. We can use our personal preset without affecting the rest of the team:


```c++
//<ti>
cmake --list-presets
```


```c++
//<o>
Available configure presets:

  "windows-x64-debug"     - Windows x64 Debug
  "windows-x64-debug-out" - Windows x64 Debug (Out)
```


## Preset Inheritance


We probably noticed something was off about the previous example. We only wanted to override one setting (`binaryDir`) of a preset that already exists (`windows-x64-debug` in the shared `CMakePresets.json` file).


Duplicating the entire preset to change one setting isn't ideal. CMake saves us from this with inheritance. Just like a C++ class can inherit the values of some other class, a CMake preset can inherit the values of some other preset. We set this up using the `inherits` key, passing the name of the base preset we want to inherit from:


<CodeFile path="CMakeUserPresets.json" status="Updated">


```json
{
  "version": 3,
  "configurePresets": [{
    "name": "windows-x64-debug-out",
    "displayName": "Windows x64 Debug (Out)",
    "inherits": "windows-x64-debug",//<h>
    "binaryDir": "${sourceDir}/out/windows-x64-debug"
  }]
}
```


</CodeFile>


Now, we only need to specify the things we want to override - `displayName` and `binaryDir` in this example. Every other value will be inherited from the shared `windows-x64-debug` preset. When the shared preset gets updated with new or changed values, that update will propagate to our personal user preset too.


<Pw>


## The Need for Structure


Inheritance isn't just for user presets; it's the key to creating a scalable and maintainable `CMakePresets.json` for the whole team.


As a project grows, the number of build configurations can explode. You might need:

- Windows, Linux, and macOS builds.
- Debug and Release configurations for each.
- Maybe a special "Address Sanitizer" build for debugging memory errors.

A flat list of presets for every combination quickly becomes a maintenance nightmare, full of duplicated JSON.


<CodeFile path="CMakePresets.json">


```json
{
  "version": 3,
  "configurePresets": [{
    "name": "windows-debug",
    "binaryDir": "${sourceDir}/build/win-dbg",
    "cacheVariables": {
      "CMAKE_BUILD_TYPE": "Debug",
      "CMAKE_TOOLCHAIN_FILE":
        "${sourceDir}/toolchains/mingw-windows-x64.cmake"
    }
  }, {
    "name": "windows-release",
    "binaryDir": "${sourceDir}/build/win-rel",
    "cacheVariables": {
      "CMAKE_BUILD_TYPE": "Release",
      "CMAKE_TOOLCHAIN_FILE":
        "${sourceDir}/toolchains/mingw-windows-x64.cmake"
    }
  }, {
    "name": "linux-debug",
    "binaryDir": "${sourceDir}/build/linux-dbg",
    "cacheVariables": {
      "CMAKE_BUILD_TYPE": "Debug",
      "CMAKE_TOOLCHAIN_FILE":
        "${sourceDir}/toolchains/linux.cmake"
    }
  }, {
    "name": "linux-release",
    "binaryDir": "${sourceDir}/build/linux-rel",
    "cacheVariables": {
      "CMAKE_BUILD_TYPE": "Release",
      "CMAKE_TOOLCHAIN_FILE":
        "${sourceDir}/toolchains/linux.cmake"
    }
  }]
}
```


</CodeFile>


The solution is to think in **layers**. We can create abstract "base" presets that define a common set of options, and then compose them together to create our final, user-visible presets.


## Creating Hidden Base Presets


A common convention is to create abstract presets that are not meant to be used directly by a developer. We can signal this by setting the `"hidden"` property to `true`.  By convention, hidden presets also have their names prefixed with an underscore (e.g., `"_base"`) but this is not strictly necessary.


Let's start refactoring our "bad" example by creating a base preset that defines a standard directory structure for all our builds.


<CodeFile path="CMakePresets.json" status="Updated">


```json
{
  "version": 3,
  "configurePresets": [{
    "name": "_base",
    "hidden": true,//<h>
    "binaryDir": "${sourceDir}/build/${presetName}"
  }]
}
```


</CodeFile>


The `${presetName}` variable automatically expanded by CMake to the `name` of the final, user-visible preset. So, when we create a `windows-debug` preset that inherits from this, the `binaryDir` will automatically become `".../build/windows-debug"`.


<CodeFile path="CMakePresets.json" status="Updated">


```json
{
  "version": 3,
  "configurePresets": [{
    "name": "_base",
    "hidden": true,
    "binaryDir": "${sourceDir}/build/${presetName}"
  }, {
    "name": "windows-debug",
    "inherits": "_base",//<h>
    "cacheVariables": {
      "CMAKE_TOOLCHAIN_FILE":
        "${sourceDir}/toolchains/mingw-windows-x64.cmake"
    }
  }]
}
```


</CodeFile>


This single base preset has already eliminated the `binaryDir` duplication from all our final presets.  If we list our presets, our `hidden` preset should not be listed:


```c++
//<ti>
cmake --list-presets
```


```c++
//<o>
Available configure presets:
  "windows-debug"
```


## Layering with Multi-Inheritance


Inheritance becomes even more useful when we realize that the `inherits` key can take an **array of strings**. This allows a preset to inherit from multiple parents.


```javascript
inherits: ["_parent1", "_parent2", "_parent3"]
```


Settings from presets that appear later in the array will override settings from earlier ones. This lets us build up our final configuration by layering a series of base presets.


Let's complete our refactor. We'll create base presets for the OS and for the build type, and then compose them.


<CodeFile path="CMakePresets.json" status="Updated">


```json
{
  "version": 3,
  "configurePresets": [{
    "name": "_base",
    "hidden": true,
    "binaryDir": "${sourceDir}/build/${presetName}"
  }, {
    "name": "_windows",
    "hidden": true,
    "cacheVariables": {
      "CMAKE_TOOLCHAIN_FILE":
        "${sourceDir}/toolchains/mingw-windows-x64.cmake"
    }
  }, {
    "name": "_linux",
    "hidden": true,
    "cacheVariables": {
      "CMAKE_TOOLCHAIN_FILE":
        "${sourceDir}/toolchains/linux.cmake"
    }
  }, {
    "name": "_debug",
    "hidden": true,
    "cacheVariables": {
      "CMAKE_BUILD_TYPE": "Debug"
    }
  }, {
    "name": "_release",
    "hidden": true,
    "cacheVariables": {
      "CMAKE_BUILD_TYPE": "Release"
    }
  }, {
    "name": "windows-debug",
    "inherits": ["_base", "_windows", "_debug"]
  }, {
    "name": "windows-release",
    "inherits": ["_base", "_windows", "_release"]
  }, {
    "name": "linux-debug",
    "inherits": ["_base", "_linux", "_debug"]
  }, {
    "name": "linux-release",
    "inherits": ["_base", "_linux", "_release"]
  }]
}
```


</CodeFile>


Each piece of configuration (`binaryDir`, toolchain, build type) is now defined in exactly one place.


The final, user-visible presets are just simple one-liners that compose these building blocks


```c++
//<ti>
cmake --list-presets
```


```c++
//<o>
Available configure presets:
  "windows-debug"
  "windows-release"
  "linux-debug"
  "linux-release"
```


Defining a new configuration is now trivial:


```json
{
  "name": "windows-asan",
  "inherits": ["_base", "_windows", "_debug"],
  "cacheVariables": {
    "ENABLE_ASAN": "ON"
  }
}
```


This `ENABLE_ASAN` variable enables **AddressSanitizer**, which we'll cover in more detail later in the course.


## User Presets as the Final Layer


This layered approach fits perfectly with the `CMakeUserPresets.json` file we saw earlier. The shared `CMakePresets.json` defines the team-wide standard configurations. The user presets file acts as the final, outermost layer for personal, machine-specific overrides.


This is the standard solution to a very common problem: how to handle paths to external tools that might be installed in different locations on different machines.


Let's imagine we were using vcpkg, and our build expects the location of vcpkg toolchain file to be provided in a variable called `VCPKG_TOOLCHAIN_FILE`:


<CodeFile path="toolchains/mingw-windows-x64.cmake">


```c++
#<cmake>
# 1. Set the target system
set(CMAKE_SYSTEM_NAME Windows)
set(CMAKE_SYSTEM_PROCESSOR x86_64)

# 2. Specify the cross-compilers
set(CMAKE_C_COMPILER x86_64-w64-mingw32-gcc)
set(CMAKE_C_FLAGS_INIT "-static -static-libgcc")

set(CMAKE_CXX_COMPILER x86_64-w64-mingw32-g++)
set(CMAKE_CXX_FLAGS_INIT
  "-static -static-libgcc -static-libstdc++")
set(CMAKE_EXE_LINKER_FLAGS_INIT
  "-static-libgcc -static-libstdc++")

# 3. Configure search for external dependencies
set(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM NEVER)
set(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY)
set(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY)

set(MINGW TRUE)
set(VCPKG_TARGET_TRIPLET x64-mingw-static)
include("${VCPKG_TOOLCHAIN_FILE}")#<h>
```


</CodeFile>


The team's standard convention might be to install vcpkg in `C:/vcpkg`, and the shared `CMakePresets.json` could reflect this:


<CodeFile path="CMakePresets.json">


```json
{
  "version": 3,
  "configurePresets": [{
    "name": "_base",
    "hidden": true,
    "binaryDir": "${sourceDir}/build/${presetName}"
    "cacheVariables": {
      "VCPKG_TOOLCHAIN_FILE"://<h>
        "C:/vcpkg/scripts/buildsystems/vcpkg.cmake"//<h>
    }
  }]
}
```


</CodeFile>


However, on our machine, we've installed vcpkg to `D:/vcpkg`.  Remember, we can still override preset values on the command line as needed:


```c++
//<ti>
cmake \
  --preset=windows-vcpkg-debug \
  -DVCPKG_TOOLCHAIN_FILE= \
    "D:/vcpkg/scripts/buildsystems/vcpkg.cmake"
```


But always remembering to do this can get annoying, so we'd prefer to use a preset instead.  Instead of modifying the shared `CMakePresets.json` and causing issues for the rest of the team, we can create a personal preset in `CMakeUserPresets.json`:


<CodeFile path="CMakeUserPresets.json" status="New">


```json
{
  "version": 3,
  "configurePresets": [{
    "name": "user-windows-debug",
    "inherits": ["windows-debug"],//<h>
    "cacheVariables": {
      "VCPKG_TOOLCHAIN_FILE"://<h>
        "D:/vcpkg/scripts/buildsystems/vcpkg.cmake"//<h>
    }
  }]
}
```


</CodeFile>


By using `inherits`, we keep all the other settings from the shared preset and only change the one thing we needs to: the path to the toolchain file.


### Hardcoded Paths are Still not Ideal


While this pattern works, hardcoding paths, even in a user preset, is not the most robust solution.  Creating a load of new presets to handle variations in a single variable is quite a lot of work.  This is particularly true when working with **build servers**, which we'll cover later.


A more flexible and standard approach is to use **environment variables**. In the next lesson, we'll see how to use the `$env{...}` syntax in our presets to read paths from the system environment, making our configurations even simpler.


## Summary


In this lesson, we expanded our understanding of CMake Presets from a simple shortcuts to an architectural tool for managing build complexity.

- **Shared vs. User Presets**: Use `CMakePresets.json` for team-wide configurations that go into version control. Use `CMakeUserPresets.json` for personal, machine-specific overrides.
- **Inheritance is Key**: Use the `inherits` key to avoid duplication. This is the fundamental mechanism for creating maintainable presets.
- **Layered Architecture**: Structure your presets by creating hidden base presets (e.g., `_base`, `_windows`, `_debug`) that are responsible for small, discrete blocks of configuration. Then, compose them into final, user-visible presets using multi-inheritance.
- **User Presets as the Final Override**: A user can create a personal preset just for themselves.  User presets can inherit from shared presets.

<Preview>


### Environment Variables and Conditional Presets


We've designed a layered preset system, but it still relies on some hardcoded paths, even if they're confined to a user-specific file. The next and final step is to remove these hardcoded values and instead read them from the system environment.


In the next lesson, we will introduce the `$env{...}` syntax to read environment variables, and the `condition` key to make presets appear or disappear based on the environment. This will allow us to create presets that can intelligently adapt to the machine they're running on.


</Preview>


</Pw>

CMake Presets Fundamentals

Environment Variables and Advanced Integration

Configure and build with CMake Presets in Visual Studio

The Power of CMake Presets

CMake: One Tool To Build Them All - Bill Hoffman

CMake Presets in CLion

What's the difference between CMakePresets.json and CMakeSettings.json?

Master advanced CMake Presets. This guide covers how to use inheritance to create scalable, maintainable presets and how to override them with personal configurations in CMakeUserPresets.json.

User Presets and Inheritance

Understanding the Basics

Practical Applications

Common Mistakes

Next Steps

Additional Resources

Assessment Preparation

Managing C++ Projects Using CMake