The Wallet Code Is Now Public

The wallet code that runs on your device is now public. If you have ever wondered exactly what a Bitcoin wallet is doing with your seed phrase, you can read it.

For most people, this changes nothing. The apps work the way they always have. But for the small slice of users who care to verify rather than trust (security researchers, auditors, the genuinely paranoid), the option now exists.

Why It Matters (a Little)

A self-custody wallet handles your private keys. There is no "undo" if a wallet behaves badly. The conservative way to evaluate one is not to read marketing copy. It is to check the code.

You probably will not. That is fine. The vast majority of Bitcoin holders use wallets without ever opening the source. What matters is that someone could.

What's Open

Everything that runs on your device: the seed generation, the address derivation, the signing logic, the encryption, the entire interface. If you are curious whether seeds are transmitted anywhere, whether telemetry is hidden somewhere, whether the cryptography uses standard libraries, the answers are in the code.

What's Not

The small server we run for blockchain queries, market prices, and optional push notifications is not open. It does not see your keys, does not store anything that identifies you, and does not need to. Anything that touches your seed lives on your device, and that part is what's published.

What to Do With This

Probably nothing. Use the wallet. The fact that the code is open is one of those background facts that should make you slightly more comfortable using bit21, in the same way it should make you uncomfortable to use a wallet whose code is hidden. That's the whole point.

If you do feel like reading some Bitcoin code on a quiet afternoon, the repository is one click away. If not, the apps are doing the same things they did yesterday.