Mastering Next.js Deployment on Cloudflare Pages: Overcoming Edge Runtime & Static Generation Challenges

August 12, 2025 development notes Next.js Cloudflare Pages Deployment Edge Runtime SSG

Deploying Next.js applications to platforms like Cloudflare Pages offers incredible performance benefits due to their global Edge Network. However, this powerful environment comes with specific constraints, particularly concerning the Edge Runtime and how it interacts with Node.js-specific APIs. This post explores common challenges and their solutions.

The Edge Runtime Paradox: fs and path Modules

Cloudflare Pages often mandates that dynamic routes run on its Edge Runtime. While highly performant, the Edge Runtime is a lightweight environment that does not support Node.js built-in modules like fs (filesystem) or path.

Problem: Your Next.js application uses fs or path to read files (e.g., Markdown blog posts) at runtime, but the deployment platform requires Edge Runtime.

Initial Misconception: Attempting to add export const runtime = 'edge'; to pages that use fs will lead to build failures (Module not found: Can't resolve 'fs'). Conversely, removing runtime = 'edge' might cause the platform to complain that dynamic routes are not configured for the Edge.

Solution: Embrace Static Site Generation (SSG) The key to resolving this paradox is to ensure that any operations requiring Node.js-specific APIs (like reading from the filesystem) happen only during the build process, not at runtime. Next.js's Static Site Generation (SSG) is designed for this.

• getStaticProps (Pages Router) / Data Fetching in Server Components (App Router): Use these mechanisms to fetch data (e.g., read Markdown files) at build time.
• generateStaticParams (App Router): For dynamic routes (e.g., blog/[lang], blog/[lang]/[slug]), generateStaticParams tells Next.js which paths to pre-render at build time. This makes the pages fully static, eliminating the need for fs at runtime.

By making your pages fully static, the output served by Cloudflare Pages will be pre-generated HTML/JSON, which is perfectly compatible with the Edge Network without needing fs at runtime.

Removing Redundant Dynamic API Routes

Sometimes, you might have dynamic API routes that were designed for server-side data fetching (e.g., /api/posts/[lang]/[slug]). If your frontend pages are now statically generated and fetch data at build time, these dynamic API routes might become redundant.

Problem: Unnecessary dynamic API routes that cannot be made static or Edge-compatible.

Solution: If an API route is no longer needed (e.g., its functionality is replaced by SSG), consider removing it. This simplifies your application and eliminates potential build conflicts with platform constraints.

By strategically leveraging Next.js's SSG capabilities and understanding the nuances of Edge Runtime, you can successfully deploy robust applications on Cloudflare Pages, delivering content efficiently to users worldwide.