Pay Like Sending an Email

Send crypto to an email address or phone number. No wallet address needed. No QR codes. Just type and send.

Blockchain Addresses Are Not Human-Readable

Blockchain addresses like 0x7a3b...4f2c are not designed for humans. They cannot be spoken aloud, cannot be remembered, and are easy to mistype. Sending a transfer requires copying 42-character hex strings — a process that is error-prone and intimidating for mainstream users.

Not Speakable

Try telling someone your Ethereum address over the phone. Hex strings are designed for machines, not conversations.

Easy to Mistype

One wrong character sends funds to a non-existent address. No confirmation, no reversal. Funds are permanently lost.

Copy-Paste Attacks

Clipboard malware replaces copied addresses with attacker-controlled ones. A common vector for theft that is invisible to the user.

Intent-Based Payment Flow

HFI-Pay uses an intent-based architecture. The sender expresses a payment intent using a human-readable identifier, and the protocol handles discovery, locking, verification, and settlement.

Send Flow

Sender email + amount
Payment Intent locked on-chain
Notification recipient alerted
Claim verify + receive

The sender specifies the recipient by email or phone number and the amount. The system creates a payment intent that is locked on-chain, bound to the recipient's DiscoveryID (HMAC-derived from their identifier). The recipient receives a notification, verifies their identity, and claims the funds. If unclaimed after a timeout period, the sender can reclaim.

Claim Flow

The recipient does not need a pre-existing wallet. When they verify their identity (email or phone), the system discovers or creates their on-chain identity via VA-DAR and releases the locked funds to their account. The first payment someone receives can also be their wallet creation event.

Cross-VM Payment Support

HFI-Pay intents can target multiple VMs within ACE Chain. When you pay to an email address, the recipient receives tokens on their preferred VM — EVM, SVM, or any other supported execution environment.

VM-Agnostic Intents

Payment intents are not bound to a specific VM. The recipient's preference determines where the funds land. Same payment, flexible delivery.

Unified Token Ledger

Because all VMs share one token ledger, cross-VM payments are just balance changes. No wrapping, no bridging, no conversion fees.

ZK Claim Verification

Claims are verified using zero-knowledge proofs. The recipient proves ownership of the identifier (email or phone) without revealing it on-chain. The verification happens off-chain, and only the proof is submitted for settlement.

Claim Verification // Recipient proves: "I own identifier X" // Without revealing: X itself ZK Proof = prove( public: DiscoveryID, // HMAC(secret, identifier) private: identifier, secret // never revealed on-chain ) // Verifier checks: // 1. HMAC(secret, identifier) == DiscoveryID ✓ // 2. Proof is valid ✓ // 3. Release funds to recipient's idcom ✓

This ensures that the on-chain record contains no human-readable information. An observer sees a DiscoveryID and a ZK proof — they cannot determine which email address or phone number was used.

Privacy by Design

HFI-Pay is built with privacy as a core requirement, not an afterthought. Payment intents are bound to DiscoveryIDs (HMAC-derived), not plaintext identifiers. On-chain observers cannot determine the human-readable recipient of any payment.

No Plaintext on Chain

Email addresses and phone numbers never appear on-chain. Only HMAC-derived DiscoveryIDs are stored, which are computationally irreversible.

Unlinkable Payments

Without the HMAC secret, observers cannot link a DiscoveryID to a real-world identity. Payment history is visible but attribution-resistant.

Use Cases

HFI-Pay transforms blockchain payments from a technical operation into a human-friendly experience. The same UX patterns that made email ubiquitous — type an address, hit send — now work for value transfer.

Person-to-Person

Split a dinner bill, pay back a friend, send a gift. Just type their email and the amount. No QR codes, no address books, no friction.

Merchant Payments

Customers pay to a merchant's email address. No payment processor integration needed. Settlement is instant and on-chain.

Payroll

Pay employees by email address. No need to collect wallet addresses. Employees receive funds and can set up their wallet when convenient.

Airdrops

Distribute tokens to an email list. Recipients do not need wallets to be eligible. They claim when ready, creating their wallet in the process.

Cross-Border Remittance

Send money across borders using a phone number. Sub-cent fees and instant settlement make micro-remittances economically viable for the first time.

AI Agent Payments

AI agents can send and receive payments using identifiers. Combined with ACE Chain's sub-cent fees, this enables autonomous economic agents at scale.

Read the HFI-Pay Research

Technical specification of the human-friendly payment protocol with ZK claim verification.