Next.js 16.3

Next.js 16.3 ships opt-in instant page navigations, AGENTS.md support for AI tooling context, Turbopack under 50ms HMR, and improved React Server Components streaming.

• Instant Navigations — add the instant prop to Link or enable globally; Next.js prefetches and caches full page payloads so clicking a link swaps DOM trees with zero loading spinners or layout shift
• AGENTS.md support — drop an AGENTS.md file in the project root and AI coding tools automatically read project conventions, architecture decisions, and style rules
• Turbopack under 50ms HMR — Rust-based bundler sustains hot-module replacement under 50ms for projects up to 10,000 modules; edge-case fallbacks to Webpack eliminated
• RSC streaming improvements — better back-pressure handling and error boundaries for server component streaming; large component trees render incrementally rather than buffering until the full render completes

Upgrade with npm i next@latest.