This article demonstrates how to build a minimal stateful process using only Elixir’s core concurrency primitives: spawn/1, send/2, receive, and recursion.

Instead of relying on GenServer, the implementation starts from first principles to explain how a process owns private state, communicates through message passing, and implements a simple request–reply protocol. Understanding these fundamentals provides a solid foundation for learning OTP abstractions and designing distributed systems on the BEAM.

Note: This is my first technical article on Elixir. The primary goal is to explain the underlying concepts as accurately and clearly as possible. If you notice any mistakes, inaccuracies, or opportunities to improve the explanations, I’d genuinely appreciate your feedback. Corrections and suggestions are always welcome.