Sorry, I framed it wrong, the problem is when I deploy to Cloudflare Pages the build fails with an error

22:05:01.912    ./workers/src/index.ts:29:47
22:05:01.912    Type error: Cannot find name 'ExecutionContext'.
22:05:01.912    
22:05:01.912      27 | 
22:05:01.912      28 | export default {
22:05:01.912    > 29 |     async fetch(request: Request, env: Env, ctx: ExecutionContext): Promise<any> {
22:05:01.912         |                                                  ^
22:05:01.913      30 |         if (env.router === undefined) {
22:05:01.913      31 |             env.router = buildRouter(env);
22:05:01.913      32 |         }

In this example it is related to workers, but prior to that I had the same issues with

functions

in the root folder of the next.js project.