TransitPal - Smart Public Transit Platform

Domain: Transportation / Smart City Type: Proprietary IP (launched on App Store & Play Store) Team Size: Multi-developer, full-stack

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The Problem

Public bus transport in Delhi serves millions of daily commuters, but the ticketing infrastructure was outdated -- paper tickets, manual fare collection, no real-time tracking, and no digital payment options. We built TransitPal as proprietary IP to solve this -- a multi-modal routing and cashless ticketing platform launched on both the App Store and Play Store. The platform was designed to:

• Enable multi-modal routing across bus and metro networks
• Provide a cashless, multi-modal ticketing engine with digital payments
• Provide conductors with electronic ticket machines (ETM)
• Support dynamic fare pricing (peak hours, discounts, night surcharges)
• Integrate with India's Open Network for Digital Commerce (ONDC)
• Offer voice-based route guidance for accessibility
• Enable WhatsApp-based ticketing for mass adoption

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What We Built

A comprehensive smart transit ecosystem spanning 6 interconnected systems.

1. Transit Ticketing API (Django)

The core backend powering mobile ticketing and conductor operations.

150+ API endpoints covering:

• OTP-based mobile authentication
• Route and stop discovery
• Real-time fare calculation with dynamic pricing
• Ticket creation, validation, and lifecycle management
• Conductor/ETM validation workflows
• Multi-gateway payment processing (Razorpay)
• Push notifications (Firebase, APNs, Web Push)

Dynamic Fare Engine:

• Base fares calculated from stop-to-stop distance matrix
• Peak hour surcharge (+Rs 5, configurable)
• Night surcharge (+Rs 10, 10 PM - 6 AM)
• Discount categories: Student (50%), Senior (25%), Disabled (75%)
• Redis-cached fare rules with 1-hour TTL for performance

Architecture:

• Django 5.1 + DRF with JWT stateless auth
• PostgreSQL with complex hierarchical data models
• Celery + Redis for background jobs and scheduled tasks
• OpenTelemetry instrumentation for observability
• AWS S3 for static assets, CodeDeploy for CI/CD

2. Operations Management System (RSC-Dev)

Internal platform for Delhi Transport Corporation (DTC) operational teams. DTC is the primary government-run public bus service in Delhi, operating a fleet of 3,700+ buses across 700+ routes serving millions of daily commuters.

• Automated breakdown reporting (15-minute cron intervals)
• Vehicle inspection tracking and scheduling
• Accident reporting and management
• Institutional hierarchy management (depots, routes, divisions)
• Dashboard analytics with daily operational reports

3. Real-Time Vehicle Tracking (GTFS-R Receiver)

Live bus position monitoring using GTFS Realtime protocol.

• Fetches protobuf-format vehicle positions from Delhi Transport API
• Parses and extracts: vehicle ID, trip ID, route, GPS coordinates, bearing, speed
• 5-minute polling intervals for continuous monitoring
• CSV output for analytics and historical tracking

4. ONDC Network Integration (NestJS)

Registered as a network participant on India's Open Network for Digital Commerce.

• Full ONDC:TRV11 domain compliance for unreserved ticketing
• Multi-environment deployment (staging, pre-prod, production)
• Cryptographic key pair generation for network signing
• Domain verification and challenge-response authentication
• Registry subscription and lookup integration
• Buyer app and seller app participant types

5. Voice AI Route Assistant

AI-powered voice assistant for Delhi Metro navigation.

• Speech-to-text via OpenAI Whisper
• Natural language route requests ("Take me from Huda City Centre to Rajiv Chowk")
• Fuzzy matching for 250+ station names (accent-tolerant)
• Route optimization via OpenTripPlanner with transfer calculations
• Text-to-speech output for hands-free navigation
• Built on Delhi Metro Rail Corporation (DMRC) GTFS data covering all 10 metro lines. DMRC operates one of the world's largest metro networks, spanning 390+ km with 280+ stations across Delhi-NCR.

6. WhatsApp Ticketing Interface

Conceptualized and presented WhatsApp-based ticket booking for mass market adoption.

• Bus route selection through conversational WhatsApp UI
• UPI payment integration (GPay, PhonePe, PayTM)
• QR code e-ticket generation
• Multi-language support
• Interactive presentation delivered to stakeholders

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Technical Highlights

Scale & Performance

• 150+ API endpoints with Swagger documentation
• Redis caching for fare calculations (sub-100ms response)
• JWT stateless auth enabling horizontal scaling
• Background job processing with Celery (scheduled reports, notifications)
• GTFS Realtime data processing at 5-minute intervals

Multi-Environment DevOps

• Staging, pre-production, and production environments
• Docker containerization
• AWS CodeDeploy for automated deployments
• OpenTelemetry for distributed tracing
• PM2 process management

Compliance & Standards

• ONDC:TRV11 domain certification
• GTFS and GTFS-Realtime standard compliance
• Government-grade security (JWT, role-based access)

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Tech Stack

Layer	Technology
Core Backend	Django 5.1, DRF, PostgreSQL, Celery, Redis
ONDC Service	NestJS 11, TypeScript
Voice AI	Python, Whisper, OpenTripPlanner, NetworkX
Real-Time	GTFS-R Protobuf, CSV analytics
Payments	Razorpay, UPI (GPay/PhonePe/PayTM)
Notifications	Firebase FCM, APNs, Web Push (VAPID)
DevOps	Docker, AWS (S3, CodeDeploy), PM2, OpenTelemetry

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Outcome

• Complete digital transformation of bus ticketing operations
• Dynamic pricing engine handling multiple fare rules and discount categories
• Real-time vehicle tracking for operational visibility
• ONDC-compliant network participant enabling cross-platform ticket sales
• Voice AI assistant making metro navigation accessible to all demographics
• WhatsApp channel concept validated with stakeholders for mass-market reach

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Key Takeaway

TransitPal is proprietary IP we built and productised, launched on the App Store and Play Store, showcasing our ability to work at the intersection of public infrastructure, AI, and modern commerce standards. We didn't just build an API -- we delivered an integrated transit ecosystem with multi-modal routing, cashless ticketing, real-time tracking, ONDC compliance, voice AI, and conversational commerce. Each component was production-grade and standards-compliant.