What’s in 15.4, what’s landing in 16, and what’s still missing
What 15.4 gave us (and why 16 matters)
Next.js 15.4 landed quietly in July 2025, but it laid serious groundwork: Turbopack was locked in with full test coverage, cacheComponents entered beta to unify Next's confusing caching behaviors, and new devtools started peeking through. There...