How A/B Testing can ruin your codebase | Swift Heroes 2025

⏩ Chapter: 00:00 03:34 Code complexity 08:14 Cleaning up finished experiments 09:06 Experiment-Induced Damage 10:33 Data corruption & loss 12:29 Testing complexity 15:17 Share state can be non-obvious 16:40 Advice on Unit Testing from Optimizely 19:01 Debugging complexity 21:29 Developer Experience 26:41 Use Experience 29:18 A/B Testing tends to be short-sighted A/B Testing: The Unexpected Engineering Nightmare exposes the rarely discussed but critical impact A/B tests can have on code quality, team productivity, and long-term maintainability. In this talk from Swift Heroes 2025, iOS Engineer Anastasia Petrova dives into real-world examples of how A/B testing, when mismanaged, can lead to code complexity, data corruption, and testing hell. From debugging unpredictability to compromised user experiences, this session walks through the hidden costs of experimentation and offers strategies to mitigate damage. You’ll learn how to clean up test code, respect user consent, avoid shared state chaos, and maintain a healthy development process without sacrificing data-driven insights. If you're running A/B tests—or planning to—this talk is essential viewing. Avoid the trap of short-term wins that lead to long-term technical debt. Watch now and build smarter, not messier. 🎤 ANASTASIA PETROVA, iOS Engineer 📍Swift Heroes is the International Swift Conference. For developers, designers & project managers at all levels of experience with Swift. Was hosted in Turin. Attended by 300+ participants and broadcast to an additional 200+ participants across the globe. 📌 For more engaging content and expert insights, subscribe to our channel and hit the notification bell. 🛎️ Inform: https://swiftheroes.com/ ✅ Tweet:   / swiftheroes_it   ✅ Connect:   / swift-heroes   ✅ Read: https://telegram.me/swiftheroes #ABTesting #SwiftHeroes2025 #iOSDev #DeveloperExperience #MobileDevelopment #TechTalks #EngineeringBestPractices #CodeQuality #AppPerformance #FeatureFlags