Buenos Aires has become one of the first cities in the world to adopt blockchain technology to manage citizens’ digital identities. The capital of Argentina recently launched QuarkID, a blockchain-based system that provides over 3.6 million residents with more control over their personal data. With QuarkID, residents can access documents like birth certificates, driver’s licenses, and academic credentials through a convenient app. This streamlined approach allows the government to efficiently manage its citizen records while reducing bureaucracy and red tape.

QuarkID runs on zero-knowledge (ZK) rollups, enabling users to verify things like age or proof of residence without sharing any extra personal information. For instance, ZK proofs can confirm that someone meets age and work eligibility requirements for a job application without revealing additional personal details like their specific age or full address.

The app supports over 60 types of official documents. Residents can share their documents with businesses or government offices as needed and verify their identity directly from the app. From confirming school records to proving residency for various services, the app speeds up these tasks, reducing the need for in-person visits and extensive paperwork.

One of QuarkID’s best features is its self-sovereign identity (SSI) model. Instead of relying on governments or companies to manage and verify personal information, SSI lets you control your data entirely, deciding when, how, and with whom to share it. Rather than using a centralized system that stores everyone’s information in a single vulnerable database, personal data is independently stored and protected on user devices. SSI uses a combination of technologies including blockchain, decentralized identifiers, and verifiable credentials to keep your information private while still allowing you to share important details when needed.  When someone needs to verify something about you, you control exactly how much information you provide.

The launch of QuarkID marks a major step toward making essential government services safer and more accessible for citizens. The goal is to lay the groundwork for a future where data ownership is a basic right, not a privilege. With QuarkID, Buenos Aires is creating a system that prioritizes privacy, providing enhanced security without compromising user control.

QuarkID’s open-source code also allows other cities and organizations to adopt it for secure login systems, fraud reduction, and broader digital ID accessibility. In the future, Buenos Aires plans to add features like expanded government service access, with hopes that Argentina will eventually roll out this technology nationwide.

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