How can constraints make software development assistants more efficient? Carl and Richard talk to Don Demcsak about his work on getting LLMs to build higher-quality software with fewer resources. Don talks about how domain-driven language techniques help to define and constrain language around a given application problem space, but that largely hasn't been applied to coding agents so far. And as powerful as domain-driven is, it has challenges when it comes to building applications - and, more importantly, testing them. That's where behavior-driven approaches have advantages, which can also be applied to agents. Applying techniques of the past to tools of the future can accelerate development even further!