Custodial wallet basics
What "your keys are protected for you" actually means — no jargon.
If you signed up with an email and password, you have a custodial account. This page explains what that means in plain terms.
You have keys — you just don't have to handle them
Every MailGate account has cryptographic keys. They're what make your account yours and what decrypt your mail.
With a custodial account, you don't type, store, or back up those keys. They're generated and protected for you inside a secure, sealed environment. You sign in with an email and password like any normal service, and the key handling happens out of sight.
Where the keys actually live
The keys are not sitting in a normal company database where an employee or an attacker could grab them. They live inside a secure enclave — a locked-down, tamper-evident environment whose exact software is verified by the blockchain before it's trusted.
A useful mental model: your key is split and sealed, and no single person or server holds a usable copy. Reading your mail requires the verified enclave and the on-chain rules to agree — there is no "master key" an insider can walk off with.
That's why MailGate can honestly say the people running it cannot read your mail, even though you never personally manage a key.
Custodial vs Self-custody
| Custodial (email + password) | Self-custody (Sui wallet) | |
|---|---|---|
| Sign-up | Email + password | Connect a Sui wallet |
| Who holds the account key | Protected for you in the enclave | You, via your wallet |
| Day-to-day experience | Like any web app | Approve actions in your wallet |
| Best for | Most people | People who already use a Sui wallet |
Neither option asks you to pay gas fees, and both give you the same encrypted inbox.
What this means for "losing access"
Because keys are managed for you, account access is tied to your email/password login rather than a seed phrase you could lose. The trade-off is the flip side: today a custodial account can't yet export its keys to become fully self-custody from inside the app — see the next page.
The planned upgrade path (not live yet)
In the future, you'll be able to migrate a custodial account to self-custody by connecting a Sui wallet you control. The intended flow looks like this:
This path isn't wired up end-to-end yet. The on-chain primitive exists, but there's no in-app UI to drive it. For now, if you want self-custody, sign up with a wallet from the start.