Feature Flags: Pitfalls and Lessons Learned from Configurable Systems Research

This article explores the potential problems of feature flags, a widely used technique in software development. While convenient, the authors argue that feature flags can lead to difficult-to-maintain code, especially concerning feature interactions, flag removal, and testing. The article reviews existing research in configurable systems and software product lines, summarizing lessons learned such as: clearly defining configuration decision-makers, choosing appropriate binding times, using standardized implementation and documentation, and leveraging techniques like combinatorial testing to improve software quality.