Next 15 what's new and migration guides here

codemods used:

react:
main migration codemod
types-react-codemod

nextjs:
async request api

Plus changed the next config file

Note: After updating deps, compile times for se-2 homepage were crazy 60-100 seconds, but then the problem eventually disappeared. Currently compile times in dev mode for me is like 8-13sec. Hopefully, for you it will work fine from the start

Things I thought about but decided it's not worth it

• https://nextjs.org/docs/app/building-your-application/upgrading/version-15#client-side-router-cache . staleTimes is experimental and also has default 5 mins for static
• https://nextjs.org/blog/next-15#turbopack-dev . Works only for dev mode and also for me server startup and compile times with and without --turbo are almost the same . I think it's better just to wait until it will become default for nextjs
• https://nextjs.org/docs/app/api-reference/config/typescript#statically-typed-links Available from next v13 but still experimental

TODOs after migration to next15

1. Update SRE extensions

• https://nextjs.org/docs/app/building-your-application/upgrading/version-15#nextfont
• https://nextjs.org/docs/app/building-your-application/upgrading/version-15#serverexternalpackages for challenge 0

2. Update Eslint to v9 and all related packages, finally

Fixes #1033