Every crypto wallet is one of two species. A custodial wallet (an exchange account, most app wallets with "cloud backup") holds keys for you. A non-custodial wallet generates keys on your device and never shares them. The marketing slogans are tired; the trade-offs are concrete.
What custody risk looks like
- Exchange insolvency: funds on a custodial platform are the platform's IOU. History's ledger of frozen withdrawals and bankruptcies needs no introduction.
- Account seizure and freezes: a custodian can freeze, censor or close your access — sometimes for your protection, sometimes not.
- Data breaches: custodians store millions of users' KYC and balances; that honey pot gets attacked constantly.
What self-custody costs
- You are the recovery department. Lose your seed phrase and the funds are unrecoverable — see the recovery map.
- You are the security team. Phishing, malware and social engineering target the weakest link: you. The scam field guide is required reading.
- No chargebacks. A mistaken send is final.
How this wallet implements non-custodial
Your 12-word phrase is generated by your browser's cryptographic random source, encrypted with AES-256-GCM where the key is derived from your PIN through 600,000 rounds of PBKDF2-SHA256, and stored only in your browser's local storage. The plaintext phrase exists in memory only while you use the wallet. There is no account server to breach because there is no account. The only network requests the app makes are to public blockchain RPC nodes and public price APIs.
Who self-custody is right for
Anyone holding an amount whose loss would hurt, for longer than a trading session. The learning curve is real but one-time: a good backup, a test transfer habit, and skepticism of every link. That skill set — not any app — is what keeps self-custody safe.
