QRPRUF is a mobile-first zero-trust proof-of-presence protocol designed to certify that a person, event, or field action happened at a specific place and time.
It generates a signed, geolocated and timestamped QR badge from a mobile device, using local evidence capture, cryptographic hashing, GPS/time validation and a verification-first architecture.
The project is part of the WITI ecosystem and was designed for high-trust field operations where presence, traceability and evidence integrity are critical.
Many field operations still rely on manual declarations, screenshots, paper forms, phone calls or trust-based reporting to confirm that an action happened on-site.
This creates several risks:
- location spoofing;
- unverifiable attendance;
- weak audit trails;
- fragmented evidence;
- delayed reporting;
- lack of trusted proof in offline or low-connectivity environments.
QRPRUF addresses this problem by allowing a mobile device to generate a verifiable proof package locally, then synchronize it later when connectivity is available.
QRPRUF provides a zero-trust mobile proof layer that combines:
- mobile identity verification;
- geolocation evidence;
- trusted timestamping logic;
- cryptographic hashing;
- QR badge generation;
- local-first proof chain;
- optional cloud synchronization;
- public or controlled verification.
Instead of trusting a user declaration, the system produces a structured proof object that can be verified independently.
- Signed QR proof badge generation
- GPS-based proof-of-presence
- Timestamped local evidence capture
- On-device cryptographic hashing
- Offline-first proof creation
- Supabase integration for synchronization and storage
- Clean Architecture and feature-driven Flutter structure
- Riverpod-based state management
- Biometric/local authentication support
- Designed for field operations, LegalTech, GovTech and compliance workflows
I designed and developed QRPRUF as the creator and software architect of the protocol.
My work included:
- defining the proof-of-presence architecture;
- designing the local-first proof chain;
- implementing the Flutter/Dart mobile client;
- structuring the application with Clean Architecture and feature-driven modules;
- integrating cryptographic hashing and evidence capture workflows;
- designing the Supabase synchronization layer;
- preparing the protocol for integration with the broader WITI ecosystem.
QRPRUF follows a modular mobile architecture focused on maintainability, security and field reliability.
Main architectural layers:
- Presentation Layer — Flutter UI and user workflows
- State Management Layer — Riverpod providers and generated state logic
- Domain Layer — proof entities, use cases and validation rules
- Service Layer — geolocation, proof generation, storage, authentication and sync
- Data Layer — local proof persistence and Supabase integration
- Verification Layer — QR badge output and proof validation logic
The system is designed to work in offline-first environments where the proof can be generated locally and synchronized later.
QRPRUF is based on a zero-trust approach:
- evidence is captured and structured locally;
- proof data is hashed before synchronization;
- GPS and timestamp data are treated as verifiable evidence inputs;
- the QR badge acts as a portable proof reference;
- cloud synchronization does not replace local proof generation;
- sensitive secrets and runtime configuration are excluded from the public repository.
The public repository is portfolio-safe and does not contain production credentials, private keys or confidential deployment data.
- Flutter / Dart
- Riverpod
- Supabase
- Local authentication
- Cryptographic hashing
- GPS / geolocation services
- Clean Architecture
- Feature-Driven Design
QRPRUF can be adapted to several high-trust scenarios:
- field agent proof-of-presence;
- legal or institutional field operations;
- certified attendance;
- delivery or service verification;
- inspection workflows;
- event check-in verification;
- technician intervention reports;
- compliance and audit trails.
This repository is a public portfolio version of the QRPRUF project.
Some production-specific configuration, credentials, private deployment details and sensitive operational data are intentionally excluded.
QRPRUF is designed as a trust layer within the broader WITI ecosystem, which also includes:
- mobile field applications;
- institutional dashboards;
- legal workflow tools;
- proof generation and verification modules.
Samir Chatwiti Software Architect | Flutter & Laravel Developer | LegalTech / GovTech / Zero-Trust Systems
LinkedIn: https://www.linkedin.com/in/samir-chatwiti/ GitHub: https://github.com/SamirChatwiti Website: https://qrpruf.com