REST, Kafka, gRPC, NATS… The list of technologies for inter-process communication is long. But when we take a step back and look at how information flows, we find just two fundamental patterns: Request-Reply and Fire-and-Forget.

This talk explores the differences between these two approaches and highlights their impact on error handling, versioning, and scalability. We’ll see that the logical communication mode is largely independent of the technology in use.

The goal is to raise awareness among developers about the implicit design decisions behind inter-process communication – and to offer concrete insights for building robust, future-proof systems.

I've seen developers choosing between Request-Reply and Fire-and-Forget without considering that this choice has implications on error handling, versioning, retry strategies and so on. Sometimes this leads to unnecessarily complicated designs during the project, and I want to bring this to the developers attention.

This is a new talk, intended for intermediate level software developers and architects.