TypeScript in LWC: What Spring '26 Actually Changes

TypeScript in LWC: What Spring '26 Actually Changes If you've been writing Lightning Web Components in plain JavaScript and crossing your fingers that your property names are spelled right, Spring '26 has something for you. Salesforce finally shipped official TypeScript type definitions for LWC base components, and honestly, it's about time. I've spent more hours than I'd like to admit debugging issues that a type checker would have caught in seconds. A misspelled attribute on a lightning-input , passing a string where a number was expected, forgetting that validity is an object with specific properties - all of it. TypeScript won't fix every problem, but it kills an entire category of bugs before your code ever hits an org. Let's walk through what's new, how to set it up, and whether it's actually worth adopting right now. What Salesforce Actually Shipped The headline feature is the @salesforce/lightning-types npm package. This gives you real TypeScript definitions for every Lightning