I wrote a deeper technical breakdown of these specific risks and the math behind the "recovery black hole" here: https://frozensecurity.com/blog/the-hidden-risks-of-using-a-...
TL;DR: Unlike your 24-word seed, a passphrase has no checksum. One typo during setup means you are sending funds into a cryptographic black hole. Digital security is useless if you fail at physical resilience.
My name is Neevai. I’m building a new Bitcoin custody product called Frozen.
The idea is simple:
Your private key is not stored in any device.
It exists only as a physical metal plate that you hold (about the size of a physical key).
When you want to sign a transaction, you insert the plate into a dedicated device.
The device reads it, signs the transaction, immediately clears all key material from memory — and only then broadcasts the transaction.
There is no digital private key stored at rest.
No secret sitting in firmware, flash, or long-term memory.
We’re launching soon and looking for feedback from serious Bitcoiners before we go live.
If this sounds interesting (or controversial), I’d genuinely appreciate thoughts from this community.