An example project with Reatom and SSR fetching and caching. Docs here:
Commit with the key changes for SSR support: https://github.com/artalar/reatom-nextjs/commit/ca0099bcddc0fbd5bc8c76eeb160f828838453d7
Try it yourself and inspect the code: https://stackblitz.com/~/github.com/artalar/reatom-nextjs