Building the digital products of a Japan-based travel company: an eSIM e-commerce platform for international tourists, a self-hosted tour booking system and an AI travel planner. Full ownership from web frontends to serverless backends and carrier integrations.
- eSIM e-commerce platform - Customer web app and admin panel (Remix, TypeScript) for purchasing, activating and topping up eSIMs
- Order fulfillment with AWS Lambda functions integrating IIJ / KDDI carrier APIs, status polling and Stripe payments
- Tour booking platform - Multilingual (ja/en/es) storefront and back office with Next.js, Supabase and atomic anti-overbooking holds
- AI travel planner - Day-by-day itineraries generated with Claude, RAG over curated knowledge, Supabase Edge Functions and Postgres
- Travel marketplace - Next.js frontend and BFF backend with Firebase auth, catalog search, quotes and checkout
Next.js
Remix
TypeScript
AWS Lambda
Supabase
PostgreSQL
Stripe
Claude API
Engineered product features for an AI-driven communication platform in a small, fast-moving Japanese team, collaborating daily with Japanese stakeholders.
- Developed web features for the 分身コール (Bunshin Call) AI calling product, deployed on AWS Amplify
- Built workflow automations with n8n and AI integrations with LangChain
- Worked end to end across mobile, web and infrastructure with a product-oriented mindset
TypeScript
React
Node.js
AWS
LangChain
n8n
Developed and maintained a ticketing web platform for events and entertainment in Uruguay, handling event listings, ticket availability and checkout flows.
- Implemented performance optimizations with Next.js ISR, reducing page load times while keeping real-time ticket availability
- Built responsive UI components with dynamic form handling for location-based features (countries, states, cities)
- Optimized caching strategies balancing data freshness with server load efficiency
Next.js
React
TypeScript
ISR
Developed mobile applications with Flutter, ensuring high performance and user experience. Designed, developed and integrated technology solutions focused on attendance management and education for corporate and academic environments in Japan.
- PitTouch 3 device integration - Connected time-clock terminals with Flutter apps and Firebase backend
- Kanril App - Modular Flutter application for attendance logging and scheduling
- T-city - Secure in-house communication app with hardened permission system
- Kanril Web - Administrative platform built with Next.js for real-time monitoring
- 2dCodeScan - QR code scanning app with offline functionality
- Trained junior developers and optimized app performance, reducing load times by 30%
Flutter
Firebase
Supabase
Next.js
TypeScript
PostgreSQL
Successfully migrated eight 2-D games developed in Unity to Flutter over the course of a year as part of a freelance project for an educational platform. Designed and implemented a complete backend using Hasura, PostgreSQL, and Node.js with TypeScript.
- Migrated 8 Unity minigames to Flutter using Flame for improved portability
- Developed backend systems using Node.js, TypeScript, and GraphQL
- Deployed on Google Cloud with Docker and Kubernetes
- Created API documentation using Postman and Swagger
- Implemented unit testing and golden tests in Flutter
- Trained junior developers, fostering team growth and knowledge
Flutter
Unity
Node.js
GraphQL
Google Cloud
Docker
Kubernetes
Engineered two full-stack mobile applications for the health and tourism sectors, implementing subscription models and payment integrations for the Japanese market.
- Developed a video-based stretching app using Flutter with native Swift and Kotlin for performance-critical features
- Created a tourism guide app for Niigata Prefecture
- Integrated In-App Purchases (IAP) and RevenueCat for cross-platform subscription management
- Implemented Firebase authentication with Google Sign-In and Apple Sign-In
Flutter
Kotlin
Swift
Firebase
RevenueCat
IAP
Earlier experience in Mexico, before relocating to Japan in 2019
Spearheaded the complete development lifecycle of the flagship Piktia iOS app, from initial architecture and UI/UX design to App Store deployment and post-launch support.
- Engineered secure user registration, dynamic photo album creation, fluid Core Animation transitions and a full e-commerce shopping cart
- Provided technical leadership: defined the MVVM architectural roadmap, conducted code reviews and mentored junior engineers
Swift
SwiftUI
UIKit
XCTest
REST APIs
Firebase
Improved audience engagement for the 'Sports World' apps by diagnosing and resolving critical bugs, refactoring legacy code and optimizing app performance.
- Partnered with Product, UI/UX and Backend teams to design, develop and launch new features within an Agile/Scrum framework
- Championed code quality by introducing unit/UI testing and rigorous code reviews
Kotlin
Swift
REST APIs
Jira
Engineered a secure and streamlined onboarding experience for the company's online banking application, with biometric login (Face ID / Touch ID) and multi-factor authentication.
- Implemented end-to-end encryption and certificate pinning to safeguard sensitive financial data
- Ensured strict adherence to PCI DSS and KYC standards, passing all required security audits
Swift
CryptoKit
Keychain
REST APIs
