S2 E9 - RxJS Operators Ep. 4: Multicasting, Error Handling, & Utility Operators

In the final part of our series on RxJS operators we welcome Zack DeRose, senior engineer at Nrwl, back to the show to learn about multicasting, error handling and utility operators. To kick things off we do a quick recap of hot vs cold Observables, unicast vs multicast, and then the Subject class as well as a few of its child-classes. You might be wondering, "What is a multicasted Observable; Why would I want that; and what is the implication for my application?" In short, the multicast operators provide the functionality to create a multicasted Observable (duh! and huh?). The complexity and confusion usually arise around what operators to choose from. Why would I choose publish() over shareReplay()? And, what about ref counting? Don't worry - panelists Aaron Frost, Brian Love, and Jennifer Wadella, along with our esteemed guest Zack, answer these very questions. We then go into detail on error handling in RxJS and the various operators for error handling, from catchError() to throwError(), and everything in between. Finally, we talk through various utility operators such as tap() and delay(). While you don't need to have listened to the first 3 episodes on RxJS operators in this series to enjoy this episode, we do recommend you check them out if you haven't already. Be sure to subscribe so you don't miss a single episode of the Angular Show! Show Notes: WTF is a cold observable: https://www.youtube.com/watch?v=4btjdWHM6lI&ab_channel=AngularSeattle DeRose Hpothesis on Code Complexity: https://www.youtube.com/watch?v=H9EZZDREMEk&t=779s&ab_channel=AngularSeattle zackderose.dev Multicasting: https://dev.to/bitovi/understanding-multicasting-observables-in-angular-2371 Connect with us: Brian F Love - @brian_love Aaron Frost - @aaronfrost Jennifer Wadella - @likeOMGitsFEDAY Zack DeRose - @zackderose The Ai Dev Craft Show is a part of the Ai Dev Craft Conference happening Master October 27-28, 2026 Las Vegas. Join us weekly as we discuss the rapidly changing AI-scape and how developers can adapt and excel. Master developing with AI, become your team’s AI expert Join us for Ai Dev Craft Get tickets now! https://ai-devcraft.com/ Special thanks to our hosts: Lara Newsom Jay Bell Mike Hartington James Spivey Brian Love