Crafting Digital Experiences
Full-stack developer turning complex ideas into simple, elegant solutions. From concept to production.
Who I Am
I'm a full-stack developer specializing in building production-ready mobile and web applications that solve real-world problems.
I work across the complete technology stack—from database design and API architecture to React components and CI/CD pipelines. I've delivered applications with real-time data synchronization, offline capabilities, and complex business logic, ensuring quality from development through deployment.
I believe great software emerges from attention to detail at every layer—clean database schemas, efficient backend services, and responsive interfaces. My goal is simple: build systems that are a pleasure to use and a joy to maintain.
Alfredo Alcántara
Full-Stack Developer
Tech Stack
Front End
- React / React Native
- Next.js
- Vue.js
- Angular
- HTML5 / CSS3
Back End
- Express.js
- Supabase Edge Functions
- Back 4 App Cloud Code
- Spring Boot
- ASP.NET Core
Database
- SQL / NoSQL / Serverless
- Supabase
- Back4app
- Firebase
CI / CD
- Render, Railway, Vercel
- Expo EAS
- Jenkins
- Docker
- AWS
What I Can Build For You
I'll build you a professional authentication system that's ready to scale. This isn't just a login screen—it's a complete, production-grade foundation for your mobile app, architected to grow with your business.
This MVP showcases what I can deliver quickly while laying the groundwork for long-term collaboration. Let's start with authentication done right, then expand based on your needs.
Starter
Perfect foundation to get started
- Full authentication flow (signup, login, password reset)
- Display & edit user information
- Supabase backend with Row Level Security
- 1 platform deployed (iOS or Android)
- Form validation and error handling
- Dark/light theme with system detection
Standard
Complete backend & full deployment
- Everything in Starter
- Express.js backend with TypeScript
- One complete CRUD feature with UI (e.g., tasks, notes)
- Deployed on both iOS and Android
- Redux for predictable state management
- RESTful API design with proper middleware
Advanced
Enterprise-ready with complex features
- Everything in Standard
- Parent-child CRUD with UI (e.g., projects→tasks, teams→members)
- Advanced state management patterns
- Optimized performance and code splitting
- Custom UI with your branding
- Comprehensive error handling & logging
Technical Excellence
Frontend Excellence
- Expo/React Native for true cross-platform
- Redux for predictable state management
- Custom UI with your branding
- Dark/light theme with system detection
- Form validation and error handling
- Responsive design for all screen sizes
Backend Architecture
- Express.js with TypeScript
- Supabase Row Level Security (RLS)
- RESTful API design
- Middleware for auth, validation, error handling
What I Build
DiviMate
Comprehensive expense app with offline-first architecture, multi-currency support, and smart debt simplification
Advanced Redux Architecture
Production-grade setup with 8+ slices, async thunks, and optimized selectors
Offline-First Architecture
Local SQLite with Supabase sync, conflict resolution, and background sync
Authentication & Authorization
JWT-based auth with OAuth integration and secure session management
Complex Business Logic
Multi-currency expense splitting with settlement algorithms and balance tracking
Multi-Channel Notifications
Email, push notifications, and encrypted deep linking with templates
Backend API Design
Three-layer MVC with type-safe Supabase operations and DTO transformation
Internationalization
i18next integration with dynamic locale switching and translations
Data Export Systems
Excel/XLSX generation
E2E Testing
Maestro test suite with 10+ scenarios covering core user flows
In-App Purchases
Expo IAP for subscription management and cross-device synchronization
Utility Library Development
Published npm package with TypeScript, AES-256 encryption and bussiness logic utilities
AI-Powered Receipt Scanning
Scan receipts with AI to automatically extract and pre-fill expense data
Production Landing Page
Live at divimateapp.com with Locomotive Scroll, custom SVG animations with Framer Motion and SEO optimization
DiviMate Crypto
Real-time cryptocurrency arbitrage monitor tracking ETH/USDC price differences between Uniswap and Sushiswap on Polygon
WebSocket Integration
Custom Redux middleware with auto-reconnection and real-time communication
Blockchain Development
Uniswap V3 and SushiSwap V3 integration using ethers.js on Polygon
Multi-Token Price Tracking
Monitor WETH, WMATIC, USDC, WBTC, USDT and more with visual trend indicators
Arbitrage Detection
Cross-DEX price comparison with gas estimation and profit calculations
Profit Calculator
Simulate trades with custom amounts and compare net profits after gas costs
Circuit Breaker Pattern
Resilience patterns with exponential backoff and rate limiting
Real-Time Data Streaming
Event-driven architecture for live updates and opportunity detection
24-Hour Analytics Dashboard
Track total opportunities, average/max profits, gas trends, and bot status in real-time
Customizable Settings
Choose display currency, select trading pairs, set profit thresholds, and theme preferences
Secure & Private
Encrypted local storage, Google Sign-in auth, read-only monitoring with no wallet connections
Gas Optimization
EIP-1559 support with configurable buffers and volatility protection
Push Notifications
Real-time alerts for high-profit arbitrage opportunities to never miss a trade
My Library
Search millions of books, import with one click, and organize your collection with categories and custom views
SQLite Database
Local database with schema design, prepared statements, and complete CRUD operations
REST API Integration
Google Books API integration with Axios for search and data transformation
Advanced Filtering
Sorting by date, title, or author with category-based organization
Image Management
Image picker with local storage and optimized handling for book covers
Context API State
Custom Provider pattern for global state management across components
Form Validation
Custom validation hooks with input sanitization and user feedback
Scientific Calculator
Two calculators in one - rotate your device to unlock 30+ scientific operations
Custom React Hooks
Reusable hooks for state management and device adaptation with clean separation
Orientation-Aware UI
Dynamic layout switches between portrait and landscape for optimal mobile experience
Error Handling
Prevents invalid operations, detects edge cases, and ensures accurate calculations
Theme System
Automatic dark/light mode switching that follows system preferences