05 · Notarization · Proof of existence
Blockchain data certification
Prove a document existed at a given date and has not been altered. We anchor its SHA-256 fingerprint on-chain: your files never leave your device and the proof is public and immutable.
Request a quote
from €790 + VAT
Deliverables
- SHA-256 cryptographic fingerprint
- Immutable timestamp
- Verifiable PDF certificate
- Bulk certification API
How we work
- 01
Specification
Requirements, architecture and a fixed quote.
- 02
Development
Contracts with tests (Foundry), frontend and staging environments.
- 03
Verification
Testnet deployment, review with you and verified source code.
- 04
Launch
Mainnet, documentation and post-delivery support.
Indicative prices excluding VAT. The final quote depends on scope, network and timeline.
Other services
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- 02Custom tokensERC-20 · SPL · Token-2022from €490
- 03Custom smart contractsSolidity · Rust · Anchorfrom €1,500
- 04Low-gas bulk transfersAirdrops · Multisender · Payrollfrom €390
- 06Smart contract auditsSecurity · Static analysis · Fuzzingfrom €1,200
- 07dApps & Web3 frontendsReact · wagmi · Wallet Adapterfrom €1,900
- 08Staking & vestingRewards · Locks · Schedulesfrom €1,100
- 09DAOs & on-chain governanceGovernor · Timelock · Snapshotfrom €1,400
- 10NFT marketplacesTrading · Auctions · Royaltiesfrom €3,500
- 11Bridges & multichain deploymentLayerZero · CCIP · Wormholefrom €2,500
- 12Real-world asset (RWA) tokenizationReal estate · Art · Invoicesfrom €3,900
- 13Consulting & tokenomicsStrategy · Modeling · Whitepaperfrom €450