Banks got one thing right: a daily limit.
However someone gets hold of your card, they can't empty your account in one go.
Why don't more self-custody wallets work like that? Small payments easy. Bi...
A few already do, using a co-signer that only signs small amounts:
• Bitkey (2-of-3): "Transfer without hardware" lets the app + Bitkey's server co-sign up to a daily limit you set; anything over it needs the hardware device. Speed-ups and consolidations always need the hardware. Limit resets 3 AM local. https://support.bitkey.world/hc/en-us/articles/19427218356500
• Blockstream app 2FA Protected / 2-of-3 accounts: set a "Two-Factor threshold"; payments below it skip the 2FA code, above it Blockstream's key only signs after 2FA. Timelock (2-of-2) or your own third key (2-of-3) means they can't lock you out for good. https://help.blockstream.com/blockstream-app/manage-2fa-accounts/set-up-a-2fa-protected-or-2-of-3-account
The tradeoff is the same as the bank: the limit is enforced by a third party's key, not by Bitcoin itself. A pure-script version (spend limits / vaults) would need covenant opcodes that aren't active.
No-trust DIY version: a small hot wallet on your phone for daily spending, and the rest on a hardware wallet or multisig at home. Refill the hot one as needed.
• Bitkey (2-of-3): "Transfer without hardware" lets the app + Bitkey's server co-sign up to a daily limit you set; anything over it needs the hardware device. Speed-ups and consolidations always need the hardware. Limit resets 3 AM local. https://support.bitkey.world/hc/en-us/articles/19427218356500
• Blockstream app 2FA Protected / 2-of-3 accounts: set a "Two-Factor threshold"; payments below it skip the 2FA code, above it Blockstream's key only signs after 2FA. Timelock (2-of-2) or your own third key (2-of-3) means they can't lock you out for good. https://help.blockstream.com/blockstream-app/manage-2fa-accounts/set-up-a-2fa-protected-or-2-of-3-account
The tradeoff is the same as the bank: the limit is enforced by a third party's key, not by Bitcoin itself. A pure-script version (spend limits / vaults) would need covenant opcodes that aren't active.
No-trust DIY version: a small hot wallet on your phone for daily spending, and the rest on a hardware wallet or multisig at home. Refill the hot one as needed.
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