Entrants from a list, file or post
Paste a list, upload a CSV file or, on Pro and Elite, import an Instagram post’s commenters as a best-effort beta. Duplicate handles are reported and entries over the plan’s limit are dropped.
INTERACTIVE 3D / PRIZE DRAWS
Nobody picks the winner.
A branded live prize-draw studio: lock the entrant list, take randomness from a public beacon, reveal the winner in 3D and let anyone re-check the result.
Drumbola
ReleasedAvailable product · current checkout availability not independently verified.
THE PRODUCT
What it solves.
A giveaway is only as trusted as its winner. Drumbola locks the entrant list before the randomness exists, derives the winner from a public drand round and keeps a draw record that anyone can re-run in their own browser. The reveal is the show; it cannot change who won.
THE ENGINEERING
How it works.
A TypeScript core fingerprints the locked list with a SHA-256 Merkle manifest and verifies League of Entropy drand quicknet BLS12-381 signatures offline, so the verifier reproduces the winner from the record alone. The studio is a Next.js static export using React Three Fiber and Three.js, with ten reveal ceremonies, served from Cloudflare Pages. Pages Functions handle Stripe subscriptions, customer branding and an append-only draw register in Supabase.
WHO IT IS FOR
Who it’s for.
Drumbola is for creators, small shops and brands that run giveaways on Instagram or on a live stream and need followers to accept the result. It suits draws of up to 500 entrants, with a branded reveal and a record any entrant can check without asking the host or DSL4.
FEATURES
What it does.
Ten reveals to choose from
From Camera Hunt and Mechanical Claw to Slot Reels and Plinko Drop. Starter and Pro hosts pick three or six and can swap them at any time; Elite runs every reveal.
A winners wall that keeps voids
Every locked draw keeps its number. A cancelled draw, an interrupted reveal or a closed page is logged as void with its reason, so a retry shows as a new draw, not a quiet swap.
CLOUDFLARE & PRODUCT ARCHITECTURE
Inside the system.
Lock first, randomise second
The entrant list is fingerprinted and locked, and the draw commits to a drand round that has not yet been published. The same list and the same round always give the same winner.
Checks anyone can re-run
A downloadable draw record can be dropped on the public verifier, which re-checks the list fingerprint, the round signature, the timing and the winner in the visitor’s own browser.
One build, many branded addresses
The app reads a customer’s brand and plan from the hostname at runtime, so each draw can run at its own dsl4.com address with its own logo and colours. Every reveal is choreographed to land on a winner the draw has already fixed.
AVAILABILITY
Status, pricing and access.
Plans are paid monthly or yearly by card, taxes included: Starter at €2.99 a month (100 entrants, three reveals), Pro at €5.99 (500 entrants, six reveals, branded stage) and Elite at €9.99 (every reveal, no credit). Cancel from the account page. The free demo takes up to 20 entrants and needs no card.
FAQ
Common questions.
- Are entrants’ handles published?
- No. The list and draw history stay in the host’s browser. The official register keeps the number, fingerprint, entrant count, times, round and outcome, with the winner stored only as a one-way code.
- What happens if drand is unavailable?
- The draw does not finish. Drumbola tries more than one drand source for a short while and accepts a winner only if the round’s signature verifies; otherwise the draw is recorded as void and can be restarted later.
- Who can run draws on my address?
- Only the host, after signing in with the operator key issued at setup, which can be reissued from the account page. Draws run anywhere else, including the free demo, never count as official draws for that address.