The Reactive Manifesto ( is several paragraphs long and lists a large number of alleged advantages of reactive programming; so many in fact, that reactive programming appears to be offered as some sort of panacea that will solve all of our problems forever.

Despite what the manifesto says, I posit that the sole purpose of existence of reactive programming is performance, in other words saving threads.

Incidentally, this means that in any environment that offers virtual threads (for example, in Java starting from version 19) reactive programming is irrelevant.

Change my mind.


Unfortunately, when people become salespersons for a certain cause, they seem to be never content with just mentioning the one game-changing advantage of their product over the competition; they seem to always have to throw as much as possible at the potential customer, in order to make them buy; so, they tend to include a torrent of inconsequential or even entirely fictitious advantages, which often has the effect of drowning the one important advantage in the noise. For example I have seen this with microservices, whose lists of advantages often contain twenty or more items, most of which are preposterous, and almost all of them are nothing but filler, because in fact microservices have just one game-changing advantage, which is scalability, or two if we want to add resilience to the picture.