Sergiy Yevtushenko is a Senior Software Architect with over 35 years of hands-on programming experience. Based in Poland, he specializes in building robust, high-performance backend systems using Java and Rust, with a particular focus on type safety and functional programming patterns that make invalid states unrepresentable.

He is the creator of Pragmatica Lite, a zero-dependency Java library providing monadic types (Result, Option, Promise) that eliminate null pointer exceptions and simplify asynchronous code. His technical writing on functional programming in Java has appeared on Medium and DEV Community, where articles like "Beautiful World of Monads" and "We Should Write Java Code Differently" have introduced thousands of developers to pragmatic functional approaches.

Sergiy's work bridges theory and practice - he believes that well-designed types and patterns can transform backend development from an error-prone craft into an engineered discipline. This book distills those insights into a practical methodology for modern Java development.