The NulloGuides.
Short, plain notes on what wallet permissions are, how they stay open, and how to read a transaction before you sign it.
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Approvals
What a token approval is, and why it outlives the app.
An approval is a standing instruction inside the token contract. Here is what it lets a spender do, where it lives, and why closing the app does not close it.
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Allowances
Unlimited allowances: convenient, and worth a second look.
Why so many apps ask for the largest possible amount, what that number means in practice, and how to decide which ones to keep.
NFTs
NFT operator approvals cover the whole collection.
setApprovalForAll is how marketplaces list your items. It is also the widest permission an NFT contract can give. What it covers and how to close it.
Signing
Read the call before you sign it.
Every revoke in Nullo shows its target, function and call data first. How to read those few lines, and why you should check them in your wallet too.