Knockin' on Header's Door: An Overview of C++ Modules - Alexsandro Thomas - NDC TechTown 2025

This talk was recorded at NDC TechTown in Kongsberg, Norway. #ndctechtown #ndcconferences #developer #softwaredeveloper Attend the next NDC conference near you: https://ndcconferences.com https://ndctechtown.com/ Subscribe to our YouTube channel and learn every day: / ‪@NDC‬ Follow our Social Media!   / ndcconferences     / ndc_conferences     / ndc_conferences   #cplusplus #language C++20 modules introduce a major shift in how code is organized and built, aiming to solve long-standing issues with headers and improve both compile times and code encapsulation. This talk offers an overview of what modules are and how they differ from traditional header files. We will cover practical considerations for introducing modules into existing codebases and designing new projects with a module-first approach, while exploring the latest and upcoming advancements of this feature as of 2025. We'll walk through the differences in compilation, visibility, and dependency management compared to the preprocessor-based model. We'll also explore the current landscape of C++ module support across major compilers and briefly examine the state of tooling integration with build systems and package managers. In addition, we’ll discuss the limitations, ongoing ecosystem gaps, and trade-offs that developers should be aware of when adopting C++ modules today. By the end of this talk, attendees will have a clear understanding of how to begin integrating C++20 modules into their projects, recognizing both the advantages and the current challenges of this evolving feature. Outline: Introduction: Why Modules? What Are C++ Modules? Traditional Headers vs. Modules Compiler Support Landscape Build Systems and Tooling for Modules Adopting Modules in Projects Current Limitations and Practical Considerations Future and Current Outlook Conclusion: The Future of C++?