Better Upload (TanStack Start)

@better-upload/server + @better-upload/client — presigned direct-to-S3 uploads via TanStack Start POST handlers and useUploadFiles / useUploadFile.

react-dropzone — optional FMC add-on for drag-and-drop multi-file UX. Add it only when the product needs that interaction (multipleFiles, batch progress). Single-file pickers, plain <input> and paste areas call upload() directly — no dropzone dependency (dropzone-ui.md).

Upstream (Better Upload): llms-full.txt · quickstart

Architecture (FMC)

Client                          Server API route                 S3
──────                          ────────────────                 ──
file picker / dropzone* onDrop
  → useUploadFiles.upload()  →  handleRequest(router)       →  PUT presigned
  → onUploadComplete         →  onBeforeUpload (auth, keys)
  → create*Fn (server fn)    →  (separate RPC, not Better Upload)
  → invalidate queries