Credify
A browser extension + smart contract system that tracks course viewing behavior to issue gasless, behavior-verified NFT certificates on Base Sepolia — proving students actually watched, not just clicked through.
Submitted Jun 22, 2026
Team size 6
Problem
Traditional online certificates are meaningless — anyone can click through a course without learning anything. LearnCert solves certificate fraud and lack of proof-of-engagement by: Verifying actual watch behavior (pauses, rewinds, attention patterns) before issuing a certificate Minting certificates as on-chain NFTs, making them permanently verifiable by anyone Removing the crypto barrier — students need zero ETH to receive their certificate (gasless...
How UGF was used
UGF was used to enable gasless NFT minting so students don't need ETH to receive their certificate. The flow works in 4 stages: Authentication — the payer wallet logs into UGF Quoting — UGF estimates the gas cost for the mint transaction on Base Sepolia Settlement — gas fee is paid using TYI_MOCK_USD (UGF's testnet token), not ETH Execution — UGF sponsors and submits the transaction to Base Sepolia on the student's behalf The result: a student with...