Use the versions pinned by the current AFFiNE repository: Node from .nvmrc, Yarn from package.json, and Rust from the repository toolchain file.
The web app is available at http://localhost:8080. Browser-local workspaces are enough for most editor and UI work. Accounts, sync, collaboration, AI, and other cloud features also require the local server.
If these commands diverge from the repository, follow the current Building AFFiNE Web guide.