HashPay Confidential — FHE-gated payroll-backed credit with zero-leak underwriting

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## The use case

Salary advances are a ~$40B/year market. To get one IRL you hand a lender

your full payroll: salary amount, employer, repayment history, credit score.

They keep it. So does their data broker. So does their analytics partner.

Onchain finance is supposed to fix this — but on a public chain "compliant

payroll" means broadcasting every paycheck to the world. That’s why

tokenized real-world cashflows have stalled at ~$27B: confidentiality is the

missing layer.

## What HashPay Confidential does

A payroll-backed credit primitive where the **salary**, the **credit

score**, and the **requested loan amount** are all encrypted — and

underwriting runs entirly under FHE.

Why this is unusual

The property I want to highlight: approval and denial are
computationally indistinguishable on-chain.

That’s the lift FHE gives you that ZK doesn’t. With ZK you could prove “I
was approved for this amount given private inputs” — but emitting that
proof reveals that approval happened. With FHE the contract literally
writes the same bytes either way; whether the borrower walks away with
$1,200 or $0 is something only the borrower can decrypt.

Concretely:

  • A competing lender watching the chain can’t tell whose advance got
    rejected, so they can’t price-discriminate on that signal.

  • A government can’t tell who borrowed and who was turned down.

  • The on-chain trace contains a request and a constant-shape disbursement
    event. That’s it.

Beyond the core advance

Eleven contracts shipped. The ones the forum will probably find most
interesting:

  • ConfidentialPayrollRoster — encrypted batch payroll. An employer
    commits a roster of (employee, encrypted amount) pairs and pays them
    all in one tx. Per-employee compensation and the total are never
    revealed.

  • IncomeProver — selective proof-of-income. The employee produces
    an ebool attesting salary >= threshold and grants ACL only to a
    named verifier (landlord, second lender, insurer). The salary never
    reaches them.

  • ConfidentialEmployerRunway — encrypted runway alerts.
    hasLowRunway(employer, N) returns an ebool; balance and burn rate
    stay private.

  • ConfidentialAdvancePositionNFT — encrypted ERC-721 position.
    Principal, rate, and status as ciphertext. Transfer hands off the ACL
    so the new holder can decrypt — secondary market without revealing
    terms.

  • ConfidentialFXOracle — encrypted FX feed so foreign-currency
    salaries can underwrite against USD-equivalent without revealing the
    pair or the rate.

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