Case study 02
QR vaccine verification
Real-time verification across five million vaccination records, during a period when the answer had to be immediate and correct.
Problem
A vaccination record is only useful if someone can verify it at the moment it matters — at a border, a workplace, a hospital desk. During the COVID-19 campaign that meant turning a national reporting database into a service that answers a single question in under a second, for millions of people, from devices and networks nobody controls.
The hard constraint was that the authoritative data already lived in DHIS2, a system designed for aggregate and programme reporting, not for high-volume public lookups.
Approach
I architected and deployed the QR-based verification service and the integration path that connected it to both the national health platform and the government's citizen-facing app.
- Designed a QR-based verification flow giving real-time access to 5 million+ vaccination records.
- Integrated with DHIS2 as the authoritative source, without putting public verification load onto the reporting platform's critical path.
- Built secure API configurations connecting the service to the Government of Nepal's Nagarik App, so citizens reached it through a channel they already had.
- Handled the integration surface across multiple systems as a set of explicit, documented contracts.
Technology
- DHIS2
- Nagarik App
- REST APIs
- QR encoding
- Secure API configuration
- Linux
- Nginx
Impact
The system made vaccination status verifiable in real time at national scale, and it did so by connecting existing public infrastructure rather than standing up a parallel one.
- Real-time verification across 5M+ vaccination records.
- Citizen access through the government's existing Nagarik App rather than a new install.
- DHIS2 established as the single authoritative source, avoiding a second version of the truth.
- A reusable integration pattern between national health data and citizen-facing services.