The text discusses the evolution of Content Management Systems (CMSs) from custom, monolithic systems to modern, modular architectures. In the 2000s, custom CMSs were common, but they didn't scale as businesses grew and new technologies emerged in the 2010s. The rise of headless CMSs and decoupled front-end architectures led to the standardization of modern CMSs as a service, providing content modeling, page building, and publishing capabilities. However, this also created challenges, such as managing multiple tools and services. By the late 2010s, technical architects began breaking out each business function into separate cloud-based SaaS services, leading to the development of modular web design architecture. This approach combines API-based services with modern JavaScript development environments to build high-performing websites, optimizing for growth and adaptability. Modular web design offers benefits such as mix-and-match building blocks, faster shipping and iteration, and maximized performance and productivity.