According to a profile by Mastercard, Trust Stamp uses biometrics to verify your identity without revealing any information:

The process is simple: The customer takes a photo of their face, palm or fingerprint and shares it with Trust Stamp. The company uses AI to create a 3D mask of it — and then throws away the data and adds encryptions in place of the name or records. "Only a small percentage of the data that originally existed is in the hash," [Trust Stamp co-founder Gareth] Genner says. "What you have is something safer for storing because it can't be used to directly identify you. No one would recognize you in this huge jumble of numbers."

The new program to be tested in West Africa will see Trust Stamp's technology integrated into the GAVI-Mastercard "Wellness Pass," a digital vaccination record and identity system.