Security
We never hold your money, and here is exactly what that means
What we can do
- Pause new buys in an emergency, and withdrawals keep working
- Lower the spending caps straight away
- Raise the spending caps, with 48 hours’ notice
- Receive the 0.25% fee on buys that fill
What we can’t do
- Move, freeze or withdraw your money
- Change where your Bitcoin or your withdrawals go
- Stop you from withdrawing
- Change the contracts after they’re deployed
Your money is in your own vault
- Every person gets their own contract on the Sonic network, and nobody else’s money is in it
- The contracts can’t be upgraded, so the rules you sign up to are the rules that stay
- Withdrawals go only to the wallet you signed up with, and Bitcoin goes only to the addresses you set when you created the vault
- To use a different delivery address you make a new vault, so nobody can quietly swap it
Limits built into every buy
- Every buy has a price floor from Chainlink’s Bitcoin price: 1.5% below the market by default, and never more than 5%
- A buy that nobody fills within 10 minutes is cancelled, and the money returns to your vault
- A buy can’t run early, twice, or above your plan’s amount and budget
- Each buy, each plan and our total volume have a spending cap, and raising a cap takes 48 hours’ notice
The price floor limits how much you can lose on a single buy. It doesn’t promise a price, and Bitcoin can still fall after you buy.
Who else you rely on
Your vault can’t do everything alone, so some parts depend on other companies. Here is each one and what it could do.
| Who | What for | What could go wrong |
|---|---|---|
| SODAX | Swaps and delivery | It can upgrade its own contracts, so money inside an open order, and Bitcoin held as its sodaBTC token between batches, depends on it |
| Chainlink | Bitcoin and USDC prices | If a price goes stale, buys pause. A wrong price would set a wrong floor, which is why every buy is also held to the spending caps |
| Bound | Co-signs the wallet for real Bitcoin | It can refuse to co-sign, but it can’t move your coins on its own |
| Coinbase and BitGo | Issue cbBTC and WBTC | A token is only as good as its issuer, and WBTC also relies on a bridge |
| SODAX relay | Lets Solana, Stellar and other non-EVM wallets act on your vault | If it’s down, your vault waits until it’s back |
If Stackk shuts down
- Anyone can run the scheduler and earn the small tip your plan pays, because the contracts don’t care who starts a buy
- With an EVM wallet you can withdraw with one Sonic transaction, through any public connection
- With a Solana, Stellar or similar wallet you rely on SODAX’s relay, so if it’s down your vault is frozen, not lost
How it’s checked
- Unit, fuzz and invariant tests on every rule
- Tests against the real SODAX contracts and Chainlink prices on a copy of Sonic mainnet
- A staged launch: a small private run on mainnet first, then low caps that rise in steps
Not audited yet
An independent audit is scheduled before launch, and a bug bounty will follow it. Nothing is insured.
Risks
Bitcoin's price goes up and down; you can get back less than you put in. Stackk is software, not a bank, and nothing is insured.