Using await in loops seems intuitive until your code silently stalls or runs slower than expected. If you’ve ever wondered why your API calls run one-by-one instead of all at once, or why map() and await don’t mix the way you’d expect, grab a chair. Let’s chat. The problem: awaiting...

Front-end developers frequently transform arrays: filtering, mapping, reducing. And sometimes grouping. Grouping used to require custom reduce() logic, which often felt like more boilerplate than it was worth. But that’s changing. JavaScript now has native grouping with Object.groupBy() and Map.groupBy(). No external libraries or reduce() patterns needed. What are Object.groupBy()...

If you’ve ever needed to search an array from the end, you’ve probably used .slice().reverse().find(...), or looped backward manually. It works, but it’s clunky. We now have a better way: Array.prototype.findLast() and Array.prototype.findLastIndex(). They search from the end without reversing anything. The problem with reversing arrays Working with lists in...