UploadThing

File hosting with no bucket to configure — you make an app in their dashboard and get a token. The quickest of the four to get working, and the smallest free tier.

npx flare create shop --storage uploadthing

It needs one package

pnpm add uploadthing

The only driver with a dependency. Flare does not install it for you, because an app that picked a different driver should not carry it.

Getting the two values

1. Sign up at uploadthing.com with GitHub or Google. The free tier is 2 GB; no card.
2. Create an app in the dashboard. The name is yours; it becomes part of the delivery domain.
3. Your app → API Keys. The token is the only value Flare needs.

Flare needs	Where it comes from	Secret?
UPLOADTHING_TOKEN	Your app → API Keys	Yes

uploadthing.com/dashboard goes there.

The token is the newer kind

UploadThing used to issue UPLOADTHING_SECRET (a sk_live_… string). The current dashboard gives a single UPLOADTHING_TOKEN, which is what Flare wants. If your dashboard still shows a secret, the token is on the same page under the v7 heading.

Putting them in

Locally, in .env (Next.js) or .dev.vars (Cloudflare) — both git-ignored:

STORAGE_DRIVER=uploadthing
UPLOADTHING_TOKEN=…

There is no UPLOADTHING_APP_ID. The token is base64 JSON — { apiKey, appId, regions } — so the app id your files are served from is already inside it, and lib/storage/uploadthing.ts reads it from there. Flare asked for it separately until 0.13.0; the two could disagree, and when they did every upload succeeded and every read 404’d from a subdomain belonging to a different app.

For production on Vercel: Project → Settings → Environment Variables, then redeploy. On Cloudflare:

npx wrangler secret put UPLOADTHING_TOKEN

Delivery URLs are public and permanent

Files are served from <app-id>.ufs.sh, and anyone with the link can read them for as long as they exist. That is the normal way to use a CDN, and the wrong way to store a medical record. To keep reads private:

STORAGE_PUBLIC=false

Every read then goes through a signed, expiring URL your app redeems.

How Flare uses it

Worth knowing, because it explains a column you will see in their dashboard. UploadThing mints its own file key on upload, while a Flare driver is asked to store bytes under a key it was given. The two are reconciled with customId, which UploadThing accepts at upload, addresses in a delivery URL and filters by on delete.

So your key stays your key, nothing has to be stored to map between them, and the customId column in their dashboard is the path your app chose. Read it at lib/storage/uploadthing.ts.

Further reading

A beginner’s guide to file uploads in Next.js covers UploadThing’s dashboard and setup in full.

It uses their SDK end to end

That guide builds an UploadThing file router, a route handler and their React components. Flare uses the package only to talk to the API — lib/storage/uploadthing.ts is the upload route, and a file field is the component. Read it for the account setup; you do not need the file router.