The rise of medium code is a new class of software practitioners who build and ship mission-critical code to production, but don't necessarily have full-stack engineering skills. These practitioners use more humane interfaces and tools to write code that is precise, testable, and has internal abstractions. Medium code allows more people to write production code more productively, and it has porous borders with traditional software development, making it easier for software engineers to integrate their work into medium-code projects. AI will accelerate this trend across multiple domains, not eliminate it, by increasing productivity and accessibility, but requiring human oversight and interpretation of output. Medium code is the ideal substrate for AI code generation due to its coarse-grained container for business logic, capturing intent and producing discrete artifacts that can be understood by domain experts. The future of medium code is accelerating with AI-native software development, enabling more people to build and ship software, making them economically valuable, and creating a powerful way to work.