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Non-Custodial Design & Approvals

DustSweep never takes custody of your tokens, and never holds a standing approval that could move them later. This page explains exactly how approvals work in each flow — and how every one of them returns to zero.

Non-custodial, concretely

"Non-custodial" is often a slogan; here is what it means mechanically in DustSweep:

  • Your tokens leave your wallet only inside the sweep transaction you approve, and the output (plus any refunds) returns to your wallet in that same transaction.
  • Between transactions, the sweep contract holds no user funds and has no ability to pull any.
  • The contract's accounting is delta-based: it can only operate on what your transaction brought in. Other users' sweeps, and anything sitting on the contract, are unreachable to you — and yours to them.
sequenceDiagram
    participant U as Your wallet
    participant R as Sweep contract
    participant D as DEX (allowlisted)
    Note over U,D: All inside ONE transaction
    U->>R: Exact amounts pulled (your authorization)
    R->>D: Approve exact amount, swap
    D->>R: Output token
    R->>R: Reset approval to 0
    R->>U: Net output + refunds for failed tokens
    Note over R: Holds nothing after the transaction

The approval lifecycle, flow by flow

One-Click / batch flow: each selected token gets an approve(sweep router, exact amount) bundled with the sweep. The sweep consumes exactly that allowance in the same transaction.

Sign & Sweep flow: tokens are approved to Permit2 (the canonical, ecosystem-shared approval contract) for the exact amounts; the actual pull then requires your fresh, expiring signature per sweep.

Inside the contract, per swap: approve the DEX for the exact amount → swap → reset the approval to zero. If a swap fails, the failure rolls back that token's approvals entirely. The contract never finishes a transaction with a live approval outstanding — in either direction.

What DustSweep never asks for

  • ❌ Unlimited (max) approvals to the DustSweep router.
  • ❌ Approvals for tokens you did not select.
  • ❌ Permission to act later, outside the sweep you are looking at.
  • ❌ Your seed phrase, private key, or any off-app "verification" — never, in any context.

Checking and revoking approvals yourself

You can independently verify all of this:

  1. Open a token-approval viewer (e.g. BaseScan's Token Approvals tool, or revoke.cash) for your address on Base.
  2. After a sweep, you will find no outstanding approval to the DustSweep router beyond amounts already consumed; in the Sign & Sweep flow you may see allowances to Permit2 — the shared mechanism also used by Uniswap and other major apps.
  3. You may revoke anything at any time; DustSweep will simply re-request the exact amounts next sweep.

A token-approval viewer showing the post-sweep state (no dangling router approvals).

User Safety Note These guarantees apply to the real DustSweep at app.dustswap.wtf. A phishing clone can imitate the interface but cannot imitate the contract's rules — which is why checking the prompt contents (exact amounts, known spender) protects you even on a perfect-looking fake. When in doubt: reject, verify the URL, retry.

FAQ

Is approving Permit2 safe? Permit2 is Uniswap's canonical approval contract used across DeFi. An allowance to Permit2 alone moves nothing — every transfer through it additionally requires your fresh signature naming a specific app, amounts, and deadline.

Why did my first sweep need more prompts than my second? First-time tokens need their exact approvals set. Later sweeps reuse what is already in place where possible.

Can the team upgrade the contract to change these rules? The sweep contract is not upgradeable; rule changes require deploying a new contract and pointing the app at it. The owner's powers are limited to the allowlist, fee (≤3% cap), pause, and rescuing stuck funds.