Both a sobering and interesting read from Stacey Tay on how the team at Carousell gathered the metrics to define a performance budget and, in turn, developed a better experience for their customers:
Our new PWA listing page loads 3x faster than our old listing page. After releasing this new page, we’ve had a 63% increase in organic traffic from Indonesia, compared to our our all time-high week. Over a 3 week period, we also saw a 3x increase in ads click-through-rates and a 46% increase in anonymous users who initiated a chat on the listing page.
The team inlined critical CSS, reduced the number of resources the app was loading, and implemented a lazy loading strategy, among many other things. I think it’s interesting to note that they also changed the design of the app in certain ways to make things more performant, too. I reckon it’s easy to fall into the trap of thinking that performance is solely a task for developers and posts like this prove that it's more collaborative than that.