Alexander is an architect and design theorist, and is perhaps best known for his 1977 book A Pattern Language. Reasoning that users are more sensitive to their needs than any architect could be, he produced and validated a "pattern language" to empower anyone to design and build at any scale. Ryan created the the software Basecamp. They both rule.
A great introduction to Christopher Alexander
Source: https://youtu.be/e3GZ5ygrLM4