Self-custody, with grown-ups.
Coinbase Custody and Fireblocks lock you into their key topology. Greenhouse is open — FROST threshold signing across your own devices, with Garden as one possible signer, never enough to move funds alone.
Transactions · Crypto Bank
Crypto custody
Self-custody wallets under FROST threshold signing. Garden holds public descriptors and HMR/Sigil lineage — private keys never leave the signer ring.
Assets under custody
Custody wallets
FROST threshold rings
Cold storage share
Wallets & assets
| Wallet | Asset | Network | Custody | USD value | Status |
|---|---|---|---|---|---|
| Treasury · cold/01 | 12.4021 BTCBTC | Bitcoin | FROST 2-of-3 | $812,440.00 | Active |
| Operating · ops/03 | 486,200.00 USDCUSDC | Solana | FROST 2-of-3 | $486,200.00 | Active |
| Reserve · cold/02 | 184.90 ETHETH | Ethereum | FROST 3-of-5 | $612,680.00 | Active |
| Payouts · hot/07 | 94,120.00 USDTUSDT | Ethereum | Single-sig | $94,120.00 | Restricted |
| Escrow · vault/11 | 220,000.00 USDCUSDC | Base | FROST 2-of-3 | $220,000.00 | Active |
| Mint float · sigil/04 | 1,480,900 MINTMINT | Sigil | FROST 2-of-3 | $148,090.00 | Active |
| Guardian · cold/paper | 3.1000 BTCBTC | Bitcoin | FROST 3-of-5 | $203,100.00 | Suspended |
FROST 2-of-3 signer ring
ProvenTransfer cold/01 → ops/03 · 8,041.06 USDC · Solana. Threshold reached; policy-checked within daily band and vendor allowlist.
Every spend, six policy checks and a partial-signature collection.
When you draft a transfer, Garden evaluates six policy checks: threshold, allowlist, daily cap, sage screen, off-hours guardrail, step-up. It then collects partial signatures across the ring. The aggregate Schnorr signature posts to chain — and to Bean as a balanced journal entry, atomically.
Transfer · 120,400.00 USDC · cold/01 → northwood:0x8f1c…
- 1CFOYubiKey 5C · sn 19284441did:oas:org:acme:cfosigned@ 16:41:24
- 2CEOLedger Nano X · acme/02did:oas:org:acme:ceosigned@ 16:42:11
- 3ops/03Garden Apex · this machinedid:agent:basil/ops-03pending
- 4AuditorTrezor Safe 3 · colddid:oas:org:acme:auditoroffline
- 5GuardianCold paper · Shamir 2-of-3guardians@anchorageoffline
- Threshold met2-of-3 required · 2 signed · waiting for 3rd
- Counterparty allowlisteddid:oas:org:northwood · whitelist age 14d
- Amount below daily cap$120,400.00 < $500,000 daily cap
- Sage screening freshscreening 4 min ago · no hits
- Off-hours guardrailoperator timezone within policy window
- Step-up signatureCFO YubiKey · touch confirmed @ 16:41:24
Self-custody that survives a guardian going dark.
Picking a custodian means trusting one company forever. Greenhouse is a key topology you own.
| Capability | Coinbase Custody | Fireblocks | BitGo | Greenhouse |
|---|---|---|---|---|
| You hold the keys | — | MPC, you co-sign | MPC | ✓ FROST, your devices |
| Hardware-backed signing | ✓ HSM | — | ✓ HSM | ✓ YubiKey, Ledger, Trezor |
| Threshold customisable | — | ✓ | ✓ | ✓ 2-of-N up to 7-of-N |
| No vendor lock-in | — | — | — | ✓ open key, exportable |
| Policy-as-code spending | limited | ✓ | ✓ | ✓ |
| Posts transfers to Bean | — | — | — | ✓ atomic |
| Agent-initiated transfers | — | — | — | ✓ with threshold + policy |
| Guardian ceremony recovery | — | — | — | ✓ Shamir-on-paper option |
Agents can initiate — never sign — alone.
An agent drafts a transfer. Signing requires the threshold. Garden's signer is one share, never the threshold. Any human can revoke their share mid-flight — the transfer dies.
What Greenhouse signs.
- 01FROST threshold Schnorr signing (no single party ever holds the key)
- 02YubiKey, Ledger, Trezor, Garden Apex, cold paper signer types
- 03Policy-as-code spending rules (per-counterparty caps, allowlists)
- 04Recovery via guardian ceremony (Shamir-on-paper supported)
- 05Native USDC on Base, Solana, Polygon, Arbitrum, Optimism
- 06Native BTC + ETH custody with HD wallet derivation
- 07Multi-sig sweep rules from hot to warm to cold tiers
- 08Posts every transfer to Bean as a balanced journal entry
Kale
