This document discusses the concept of "marginal gains" in software development. It describes how small improvements in many areas, such as the developer's skills, tools, and processes, can lead to significant overall gains in productivity and performance, just as marginal gains achieved success for British Cycling. The document provides examples of marginal gains that could be made for developers, including improving language fluency, tool and framework knowledge, desk and chair ergonomics, keyboard usage, monitor setups, IDE customization, logging and debugging practices, work item definition, meeting processes, coding standards, testing, and continuous integration. It argues these small changes applied systematically across many areas could yield performance increases of 30-40% over traditional approaches to software development