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It's Probably You
Field Notes on Checking What You Believe as an Engineer
This book is 100% completeLast updated on 2026-10-04
Thirty-two short field essays for engineers, with practical checklists and questions for team discussion. From your first years on the job to leading your first team, use these accounts to examine a decision you face: what you believe, what you can check, and what remains uncertain.
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About
About the Book
Thirty-two short field essays for engineers, with practical checklists and questions for team discussion. From your first years on the job to leading your first team, use these accounts to examine a decision you face: what you believe, what you can check, and what remains uncertain.
A crash collector handling twelve million app loads a day still needed checks for losses along its reporting path. A server passed its load test while leaking a gigabyte an hour. Diagnostic data remained locked inside an instrument, and a proposal stalled on its way up five management layers. Ilhwan Seo, who built the crash collector and led a fifty-person platform organization, describes the constraints behind these experiences and the limits of what he verified.
The book combines workplace accounts with clearly marked explanatory examples, including a review of AI-generated cancellation code. Read an essay for the problem in front of you, use the review record to compare expected and observed results, or bring a discussion question to your team. Product managers and other colleagues who work with engineers can start with the chapters on communication and schedules.
Author
About the Author
Ilhwan Seo
Ilhwan Seo is an engineer who built a crash-collection system used by more than two hundred games, is a named inventor on roughly forty registered patents, led a platform organization of fifty people, and then returned to building and releasing apps and games on his own. He has developed software and led engineering teams in games, diagnostics, recruitment, and e-commerce.
He wrote GROWTH DEVELOPER in 2019 and has continued writing about developers’ work and growth. After years leading engineering organizations, he also returned to building and releasing apps and games himself. While using AI tools, he continues to value the engineering fundamentals of understanding a problem and verifying the result.
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