🔑 Wallet & signing guide

Thimbly never holds your coins. You sign each bet in your own Bitcoin wallet — and you receive a pre-signed refund before you're asked to sign anything, so your coins are safe even if the dealer disappears.

What you need

A wallet that (a) handles Taproot and (b) can sign a PSBT containing an input it doesn't solely control. Two are tested:

• Sparrow (recommended) — use version 1.9.1 or newer (older builds had a PSBT-signing regression).
• Bitcoin Core — with a descriptor (Taproot) wallet.

Other wallets can work if they're Taproot-capable and sign PSBTs, but the steps below assume Sparrow.

Why Taproot specifically?

The whole point of Thimbly is that a bet looks like an ordinary payment on-chain — and the private, script-free way you claim a win is a Taproot key-path spend. Both depend on Taproot (P2TR) addresses. A legacy or SegWit-v0 wallet can't produce what the protocol needs, so nominate a Taproot receive address:

• Sparrow: a wallet whose Script Type is Taproot (P2TR).
• Bitcoin Core: a bech32m address (a tr() descriptor wallet).

This is signet (for now)

The public demo runs on signet, a Bitcoin test network — the coins have no real value. Get some free from a faucet (e.g. signetfaucet.com) and send them to your wallet first. Put your wallet on signet (Sparrow: Tools → Restart In → Signet), and set the network picker on the main page to signet before connecting.

Signing a bet, step by step

1. Connect to the dealer, then nominate a Taproot receive address from your wallet (the one holding the coins you want to bet).
2. Choose your total stake and place the bet. The page builds a funding transaction and shows you exactly what it moves before anything is signed.
3. At the signing gate, open the transaction in your wallet:
   • Sparrow: File → Open Transaction → From Text, and paste the PSBT.
   Review it: your coin goes in, one unrecognizable Taproot output is the shared pot, and your change comes back to you. Click Sign.
4. Send the signed transaction back to Thimbly:
   • Sparrow: after signing it shows a finalized-looking hex and no paste box — use File → Save Transaction to write a .psbt file, then click load .psbt file at the gate.
   • Wallets that give you base64/hex text can paste it into the gate's box instead.
5. The dealer counter-signs and broadcasts the funding. From here the bet plays out; if you win, you claim the pot with a plain key-path spend — indistinguishable from a normal payment.