This post introduces the use of ReactiveX programming with RxJS Observables and REST APIs in Node.js. The author guides readers through a case study project that determines the "best" movie by Quentin Tarantino based on review scores retrieved from a mock API. The project demonstrates how to perform asynchronous data retrieval, manipulate data as it arrives, and combine multiple observables to achieve a result. The post also covers the use of various RxJS operators, such as `map`, `flatMap`, and `combineLatest`, to perform actions on the emitted data and accumulate responses from multiple APIs. Finally, the author provides tips on how to add an interactive element to the command-line output using the ora library and stop a spinner once the results are ready.