blank.

Private amounts for public Ethereum payments.

Sender and receiver remain public. Payment amounts stay encrypted.

Launch app | Whitepaper | Pitch deck | Proof deck | Status | Brand kit | Blog

What Blank Is

Blank is confidential payment infrastructure for public blockchains. It is built for payments where public amounts expose commercially sensitive information: invoices, vendor payments, payroll, fundraising, commerce, and settlement.

Blank encrypts amounts in the browser and settles encrypted state through Fhenix CoFHE contracts on public testnets. It is not a mixer and does not conceal who transacted or that a transaction occurred.

Privacy Boundary

Public on-chain	Encrypted or permission-gated
Sender and recipient addresses	Payment amounts
Network, timing, contract calls, transaction hashes	Configured aggregate values and threshold checks
Public lifecycle transitions, such as created or settled	Decryption output where a permit is required

Product Surface

Area	Available capabilities
Payments	Encrypted sends, payment requests, invoices and batch payments
Shared money	Groups, gifts, claim links, inheritance planning
Commerce	Storefront purchases, crowdfund campaigns, encrypted escrow
Exchange	Private token exchange, cross-chain bridge interface, P2P offramp flow
Identity and proofs	Payment handles, public payment pages, payment receipts, encrypted proofs, proof of balance
Account safety	Guardian recovery surfaces, privacy controls, activity history

Important Product Boundaries

• Storefront records payment and purchase state. Digital-item delivery is seller-handled today.
• Offramp contracts and UI are available on testnet; the proof path uses the declared testnet verification setup until production provider and arbitration controls are activated.
• Scheduled-send authorization surfaces are present; automated execution is not yet a supported testnet capability.
• Testnet assets only. Blank is not available for mainnet value.

Live Testnet

Network	Chain ID	Application	Explorer
Base Sepolia	84532	Open app	BaseScan
Ethereum Sepolia	11155111	Open app	Etherscan

Public surfaces:

Resource	URL
Product site	www.myblank.app
Application	app.myblank.app
Technical paper	docs.myblank.app
Brand system	brand.myblank.app
Writing	blog.myblank.app/blog
Network status	www.myblank.app/status

The current public testnet scope supports standard EVM wallets across both Sepolia networks. Smart-account and sponsored transaction surfaces exist in the product, with operational readiness dependent on funded paymasters and dedicated qualification.

Responsive screens are available. Full mobile transaction qualification remains separate from the desktop testnet scope.

How Amount Privacy Works

1. The browser encrypts the payment amount before it reaches the contract call.
2. CoFHE validates encrypted input and makes ciphertext available for permitted contract computation.
3. Blank contracts update balances, totals and conditions while amounts remain ciphertext.
4. Authorized users request permitted decryption only where a product flow requires revealed output.

User input
   |
   v
Client-side encrypted amount + proof
   |
   v
Blank contract on Sepolia <-> Fhenix CoFHE coprocessor
   |
   v
Encrypted state update on a public chain

Architecture

Layer	Responsibility	Primary code
Web application	Wallet interaction, encrypted input, transaction UX, public pages	packages/app
Smart contracts	Vaults, payments, commerce, proofs, recovery and exchange state	packages/contracts
CoFHE integration	Encrypted inputs, ACL permissions and FHE operations	packages/contracts/contracts
API and indexing	Health, metadata, events and operational endpoints	packages/app/api
Product documentation	Architecture, threat boundaries and public specification	docs

Contract families include encrypted vaults and payments, business and creator workflows, commerce and escrow, exchange and offramp, handles and recovery, and privacy proofs.

For the public product documentation, start with the docs index.

Testnet Deployments

The following contracts are currently deployed on both supported testnets.

Contract	Base Sepolia	Ethereum Sepolia
FHERC20Vault_USDC	0x789f...ff23	0x3a58...AB51
PaymentHub	0xF420...e831	0xB628...b5eB
BusinessHub	0xEfD6...1EFD	0x3048...5717
ClaimLinks	0x2eD7...4665	0x9E21...12Be
Storefront	0xeA8a...d419	0x786C...695b
EncryptedCrowdfund	0x0F21...183C	0x383B...24e1
EncryptedEscrow	0x6414...e421	0x4253...0feC
P2PExchange	0xDa60...f116	0x5339...A054
P2POfframp	0xd717...32f9	0x5981...444a
ProofOfBalance	0x25e7...36Ff	0xff0F...1856
GuardianModule	0x4fa2...5B46	0xdBE8...0c3E

Complete machine-readable deployment manifests:

• Base Sepolia deployment
• Ethereum Sepolia deployment

Repository

blank/
|-- packages/
|   |-- app/                 React application, API routes and live QA flows
|   `-- contracts/           Solidity contracts, deployments and tests
|-- docs/                    Product documentation and launch scope
`-- README.md

Develop Locally

Requirements:

• Node.js 20+
• pnpm 10+
• A browser wallet for interactive testnet use

git clone https://github.com/Pratiikpy/blank.git
cd blank
pnpm install --frozen-lockfile

cd packages/app
pnpm dev

Create local environment configuration only for flows that require RPC, indexing or operational integrations:

cd packages/app
cp .env.example .env

On Windows PowerShell:

Copy-Item .env.example .env

Validation

Application:

cd packages/app
pnpm run ci
pnpm exec vitest run
pnpm check:voice:strict

Contracts:

cd packages/contracts
pnpm exec hardhat compile
pnpm exec hardhat test
pnpm storage:check

Operational testnet verification scripts are maintained with the application in packages/app/e2e. Public health is visible at www.myblank.app/status.

Security And Release Boundary

• Blank protects amount confidentiality, not participant identity or transaction existence.
• Ciphertext permissions and decryption rely on the CoFHE access model and its network assumptions.
• Upgradeable contracts are guarded by storage layout checks in development and CI.
• The storefront does not yet provide automatic digital file fulfillment.
• The offramp is a testnet product surface; production-grade provider verification, dispute operations and governance controls remain release gates.
• Mainnet use is not supported before an external audit, Fhenix production readiness, finalized operations and key-management controls.

Security issues should be reported according to SECURITY.md.

Read More

Document	Purpose
Whitepaper	Privacy model, architecture and security boundary
Pitch deck	Product story, market framing and founder context
Proof deck	Public testnet evidence and supporting material
Brand kit	Identity system and public assets
Blog	Technical and product writing
Docs index	Public repository documentation
Launch readiness	Testnet scope and release boundaries

Contributing

Please read CONTRIBUTING.md before opening a pull request. Security reports must go through private channels described in SECURITY.md, not public issues. Behavior expectations are documented in CODE_OF_CONDUCT.md.

License

MIT. Built with Fhenix CoFHE.