Developer Builds Full-Chain DID App Where System Acts as Both Verifier and Issuer

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A developer has published a tutorial demonstrating a decentralized identity (DID) application that handles both credential verification and issuance within a single workflow. The system is built around a lobby reception scenario where an employee presents a digital wallet card to endorse a visitor, after which the system immediately issues a temporary, expiring visitor pass to the visitor's wallet. Unlike traditional paper-based visitor logs that collect and store personal data, the digital approach retains only one accountable data point — which employee provided the endorsement — while visitor information stays in the visitor's own wallet. The project was deployed as a standalone Cloud Run service with a static frontend, clean API separation, and wallet interactions abstracted into a reusable library. The developer also documented three development pitfalls encountered along the way, noting these real-world lessons as among the most valuable takeaways from the build.

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