The article shares 20 lessons learned by a software engineer over their 20-year career, covering topics such as the importance of understanding the context of advice, the value of humility, and the need to focus on delivering value. The author emphasizes that software engineering is a complex and nuanced field, and that there is no one-size-fits-all approach to success. The lessons are drawn from the author's experiences working in small and large teams, and are intended to be applicable to a wide range of software engineering contexts. The article concludes by encouraging readers to share their own experiences and lessons learned.