I’ve been thinking about the destination problem in post-quantum Bitcoin discussions. A lot of current work focuses on migration: how vulnerable coins could be moved under current rules, or how users might buy time if current signature assumptions weaken. That seems useful, but it still leaves an open question:
If the goal is to stay native to Bitcoin, where does the coin actually live afterward?
The direction I’ve been exploring is an opt-in Bitcoin PQ vault lane on mainnet. The idea is that any existing Bitcoin UTXO could enter a native post-quantum vault path, remain there under PQ vault and recovery rules, and later exit back to any native Bitcoin lane.
So this is not a bridge idea or an L2 pitch. It’s a question about whether Bitcoin eventually needs a native post-quantum resting place for value, not just migration techniques.
This seems related to the current BIP 360 direction, but I think it points at a gap. BIP 360 looks useful as structural groundwork for a vault-like output model, but not as a complete PQ destination by itself. My intuition is that a complete version of this probably needs both:
-
a vault-oriented output structure, likely something Merkleized
-
and a native post-quantum authorization path
A few questions I’d be interested in hearing thoughts on:
-
Is “native PQ vault lane” a useful way to frame the destination side of the problem?
-
If Bitcoin ever adds a PQ authorization path, is vault/recovery the right first use case?
-
Does “enter from any native lane, exit back to any native lane” feel like the right design goal?
I’m asking this as an architecture question first, not a polished final proposal. I’ve been working through an architectural design for this and would be happy to share more detail if the direction seems worth exploring.