diff --git a/packages/next/build/entries.ts b/packages/next/build/entries.ts
index db3f6292df69..cde116766a2f 100644
--- a/packages/next/build/entries.ts
+++ b/packages/next/build/entries.ts
@@ -109,7 +109,7 @@ const cachedPageRuntimeConfig = new Map<string, [number, PageRuntime]>()
 // could be thousands of pages existing.
 export async function getPageRuntime(
   pageFilePath: string,
-  nextConfig: NextConfig
+  nextConfig: Partial<NextConfig>
 ): Promise<PageRuntime> {
   if (!nextConfig.experimental?.reactRoot) return undefined