Why Patching Globals Is Harmful

Kettanaito argues that patching global APIs such as fetch is harmful, citing recent examples from Next.js, React and Bun. He points to three harms: maintenance, since patching modifies code the author does not own and can clash with third-party SDKs; predictability, since Next.js's next.revalidate option leaks a framework-specific behavior through the global fetch; and learning, since such APIs teach users the tool rather than the underlying web concept. He says he reached out to Lee, who explained that next.revalidate focuses on Incremental Static Regeneration rather than just caching.