EventCHI
EventCHI is a full-stack event management platform handling ticketing, vendor marketplaces, point-of-sale payments (including NFC wearable bands), and real-time analytics. The backend is a NestJS monorepo with a Kafka worker for async event processing, PostgreSQL via Prisma, Redis for caching and pub/sub, and integrations with Stripe, Xendit, and Hyperswitch for multi-provider payment processing. An AI/RAG microservice built in Python/FastAPI handles automated product generation and multilingual content, powered by Weaviate vector DB and Azure OpenAI. The system serves web (React PWA + admin backstage), mobile (React Native), and POS clients through a KrakenD API gateway.
Screenshots
System Architecture
Service or component Connection Data flow
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Key Contributions
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AI product generation engine Show details Hide
Python/FastAPI service integrating Weaviate vector DB for document retrieval, OpenRouter and Azure OpenAI for LLM inference, SerpAPI + FAL for image search and generation. Auto-generates product listings and translates changelogs across 8 languages.
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Multi-channel notification infrastructure Show details Hide
Designed Push-to-SMS fallback with failed-message recovery. SmartNotificationUtil with Firebase push provider (18 unit tests), Dead Letter Queue service, Redis pub/sub publishWithRetry, 35 integration tests on WebSocket service.
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POS payment backend Show details Hide
Built NFC wearable and door-sale ticket checkout with multi-provider support — Hyperswitch/Xendit/Stripe integrations, eligibility filtering, transparent pricing breakdowns, Decimal(16,8) migration across 12 token fields in PostgreSQL/Prisma.
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Real-time WebSocket infrastructure Show details Hide
Unified sendToUser method for Crew/Event/Token/Vendor domains, pod-aware broadcast, authentication close codes, 35 integration tests, fixed production-blocking connection-lifecycle bugs on React Native client.
