BTC_VAULT

Bitcoin vault design (extreme cold storage)

Same economic pattern as Solana: lock BTC on the internet → mint MESH claims on the mesh → burn MESH to unlock BTC.

Mesh remains the offline truth for the claim. BTC custody is a separate internet-facing module.

Recommended v1: federated multisig vault

User BTC ──► N-of-M multisig vault (cold/watch-only operators)
                    │
                    │  attestation (deposit seen, amount, mesh short id)
                    ▼
              Bridge relayers ──Mint──► MeshChain
                    ▲
                    │  final Burn + PQ auth
              User redeems offline mesh
                    │
                    ▼
              Multisig pays BTC to fresh address

Piece	Choice
Custody	2-of-3 or 3-of-5 multisig (HW + geo separated)
Deposit detect	Watch-only xpub / electrum / bitcoin core ZMQ
Mesh credit	Mint with asset_id = 2 (BTC-claim), external_ref = txid trunc
Redeem	Burn with asset_id = 2, redeem_hint = hash(btc_address) + PQ if large
Double-pay guard	Unique burn_txid record (same idea as Solana WithdrawRecord)
Fees	Taken in BTC at deposit/withdraw; mesh gets net amount

Why not “run Bitcoin consensus on LoRa”?

Impossible at useful security. Mesh holds claims; Bitcoin holds settlement.

Optional later designs

1. DLC / adjudicator — more trust-minimized unlock conditions
2. Liquid / Fedimint — faster pegs for community operators
3. On-chain covenants (when available) — vault script enforces burn proof

Mesh multi-asset tags

asset_id	Meaning
0	Generic MESH / test
1	SOL / SPL vault claim
2	BTC vault claim

Balances may stay unified MESH units with off-mesh policy that 1 unit = 1 sat or 1 USDC — publish the peg in genesis notes. Future: separate balance maps per asset_id.

Operational cold policy

• BTC multisig keys never on the mesh radio host
• Mesh cold key (ML-DSA-65) never on the BTC signing machine
• Redeem requires both: mesh Burn finality and multisig ceremony
• Prefer new BTC receive address every unlock

Implementation order

1. Solana vault live (done as program + events)
2. Relayer Mint/Burn for SOL
3. BTC watch + multisig coordinator (this doc)
4. Unified CLI: mesh cash-out btc …