DATUM (Decentralized Ad Targeting Utility Marketplace) is an experiment in on-chain programmatic advertising on Polkadot Hub using pallet-revive (PolkaVM).

Users earn DOT for attention — all browsing data stays on-device, with only a Blake2-256 hash-chain claim submitted on-chain. Advertisers get cryptographic impression attestation. Publishers embed a lightweight SDK and settle directly via smart contract. No ad server, no tracking pixels, no user profiles leaving the browser.

13 Solidity contracts compiled to PolkaVM, currently live on Paseo testnet.