Next.js v16.5.0-canary.42 released with Request Insights updates and automatic route handler response compression
Vercel published Next.js v16.5.0-canary.42 on its GitHub releases page on 2026-11-05. The canary includes changes to Request Insights, automatic compression of route handler responses, an SWC bump to v84, and the removal of optimizeImage from the public next/image-optimizer-transform API, along with several Turbopack fixes.
Why it matters
Route handler responses are now compressed automatically when not already compressed, which can change response sizes and headers for API endpoints. Removing optimizeImage from the public next/image-optimizer-transform API breaks any code that imported it directly. This is a prerelease canary, so behavior may change before a stable release.
Who should care
Next.js developers, teams running API route handlers, teams using next/image-optimizer-transform directly, and ecommerce builders on canary channels.
What you can do
If you use next/image-optimizer-transform, check your imports against the release notes and plan a migration before upgrading past this canary.