Next.js 15 New Features and Upgrade Guide: Migrating Your Project

Wed, 08 Jul 2026 10:00:00 +0900

Next.js 15 is officially released, built on React 19 stable. This major update brings a stable Partial Prerendering (PPR) system, a revamped caching strategy, and Turbopack integration for development builds.

This article walks through the key new features and provides a step-by-step upgrade guide for migrating from Next.js 14.

1. Key New Features

Native React 19 Support

Next.js 15 fully embraces React 19. Server Components are now stable, and new hooks like use() and useOptimistic() work directly within the App Router. Server Actions are also more efficient with improved performance for action-oriented hooks.

Developing Browser Extensions with Manifest V3

Fri, 10 Apr 2026 12:00:00 +0900

Manifest V3 is now the official and mandatory specification for building Google Chrome extensions. With the deprecation of Manifest V2, developers must adopt non-persistent Service Workers for background processing and adapt to the declarative net request model. This guide explains the core architectural shifts in Manifest V3 and provides a simple walkthrough of setting up a compliant extension.

1. Primary Shifts from Manifest V2 to V3

Manifest V3 (MV3) was designed to make browser extensions more secure, privacy-respecting, and performant.

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Next.js 15 New Features and Upgrade Guide: Migrating Your Project

1. Key New Features

Native React 19 Support

Developing Browser Extensions with Manifest V3

1. Primary Shifts from Manifest V2 to V3