Private
Bearer Notes
for Bitcoin
ArcMint issues cryptographic bearer notes backed by BTC — privately, with full accountability. No separate token. No custodial risk. Threshold-secured by a FROST federation, settled via Lightning.
Built on proven cryptographic foundations
How ArcMint Works
Four steps from Bitcoin to private e-cash — secured by mathematics, not trust.
Register
Zero-knowledge identity
Sample a secret identity scalar. Commit to it cryptographically. The federation registers your commitment — not your identity. You stay completely private to everyone except yourself.
Issue
Threshold-signed bearer note
Submit multiple note candidates. The federation challenges all but one using cut-and-choose. The survivor is threshold-signed by FROST signers. Your note is now a cryptographic bearer instrument.
Spend
Anonymous proof of ownership
Present your note to a merchant. Respond to a random challenge with a selective opening proof. Your identity is never revealed. Double-spend detection is cryptographic and automatic.
Settle
Bitcoin-anchored, Lightning-fast
Redemption via Lightning is instant. Every issuance and spend is Merkle-committed to Bitcoin every 10 minutes. Provably settled, publicly auditable — forever on-chain.
Double-spend detection is automatic — if a note is spent twice, the spender's identity is mathematically recovered. No trusted party required.
Built for Institutions,
Secured by Mathematics
Every component of ArcMint is designed with an institutional-grade threat model in mind. No shortcuts, no trusted parties, no extra tokens.
Threshold Signing
FROST 2-of-3 signatures across an independent federation. No single party can forge, censor, or selectively block notes. Quorum compromise is required to break security.
Cryptographic Privacy
Pedersen commitments and selective opening proofs mean merchants learn only that a note is valid — nothing about who is spending it.
Bitcoin Native
Notes are directly redeemable for BTC. No wrapped token, no bridge, no custodian. The value is always Bitcoin.
Lightning Settlement
Instant redemption via LND. Sub-second payment confirmation, full HTLC security, and native Lightning routing.
Accountable Anonymity
Unique to ArcMint: double-spenders are automatically and mathematically identified — without compromising honest users. Accountability without surveillance.
Bitcoin Anchoring
Merkle roots of all issued and spent note serials are committed to Bitcoin via OP_RETURN every 10 minutes. Fully auditable.
A Federated Network
You Can Trust
ArcMint is built around a threshold federation where no single node has power. All inter-service communication uses mutual TLS. Your notes are cryptographically secured end-to-end.
Mutual TLS everywhere
Every service has its own certificate signed by a federation CA. Inter-service communication is fully authenticated and encrypted.
No coordinator trust
The coordinator orchestrates but cannot forge notes. FROST threshold signing requires quorum of independent signers.
Atomic double-spend registry
SQLite WAL with BEGIN IMMEDIATE transactions ensures zero race conditions in the double-spend registry. PostgreSQL migration is in progress.
Docker Compose deployment
Full federation including Bitcoin Core, LND, and all services launches with a single command. Production-ready with env var secrets validation.
Production-Grade
Security Posture
ArcMint has undergone a thorough internal security review. All critical and high findings are resolved. Zero compiler warnings. No unsafe code.
Audit Findings
Cryptographic Hardening
Code Standards
Built for Real-World
Bitcoin Settlement
From OTC desks to merchant payments, ArcMint provides the privacy layer that professional Bitcoin operations need.
OTC Desk Settlement
Transfer large Bitcoin values between counterparties with full privacy and instant confirmation. No transaction graph. No exposure to block timing.
Notes are threshold-signed and bearer — hand them off like physical cash, but with cryptographic guarantees neither party can forge.
Institutional Clearing
Multi-party settlement across desks or entities without any party learning the counterparty's position, timing, or volume.
The federation holds no value — it only signs. Clearing happens at the cryptographic layer, not via an intermediary custodian.
Private Merchant Payments
Accept Bitcoin privately. Verify notes cryptographically without learning anything about who is spending — just that they can.
Merchants receive standard Lightning payments. The privacy layer is transparent to their stack — just a faster, cheaper, more private input.
Deploy Your
Federation Today
A full ArcMint federation — Bitcoin node, Lightning, threshold signers, gateway, and merchant — launches with a single Docker Compose command.
Open-source under MIT license · Requires Docker · Bitcoin mainnet or regtest