Martín Hernández

Full-Stack Developer @ Austral Solutions

Independent Contractor

Digital wallets and a fintech SaaS platform (+Pay, Billetera País), where every line of code moves real money: secure transactionality and real-time experience as the foundation, not decoration.

• End-to-end interfaces with React, Next.js and TypeScript: authentication, balance management and instant transfers.
• Data layer with TanStack Query and TanStack Router: server state synced, cached and always fresh, with typed, error-proof navigation.
• Live movements over SignalR/WebSockets: balance and operations reflected instantly, no reload.
• Custom software for clients and companies: from problem definition to a maintainable production solution.

• React
• Next.js
• TypeScript
• TanStack Query
• TanStack Router
• SignalR
• WebSockets

Full-Stack Developer @ Asociación Consultora Mutual

Independent Contractor

• Scalable architectures with Next.js (App Router) and NestJS: modular, maintainable systems.
• Integrated financial APIs and payment gateways with secure transactions.
• Complex state handling with Zustand.
• Optimized queries and data modeling with PostgreSQL and Prisma.
• Code Review cycles and testing strategies for production stability.

• Next.js
• NestJS
• Zustand
• PostgreSQL
• Prisma
• TypeScript

Full-Stack Developer & Consultant @ Freelance

Independent clients · concurrent work

End-to-end design and delivery of digital products —multi-tenant SaaS, e-commerce and fintech— from requirements gathering and UX/UI design to deployment and production operation.

• Multi-tenant SaaS: architecture and implementation of platforms from scratch —monorepo, modular backend by bounded context, per-tenant isolation, plan-based billing, realtime and admin panel—, applying Clean/Hexagonal Architecture and scalable systems.
• E-commerce: scalable platforms (renewable energy sector), optimizing Core Web Vitals and integrating payment gateways.
• Fintech: technical lead on digital wallet interfaces, prioritizing security, accessibility and complex user flows.
• UX/UI design: information architecture, wireframes and high-fidelity prototypes focused on conversion and usability, from design to code (design systems, atomic design, multi-brand theming).
• Web platforms: high-performance web apps and PWAs, focused on performance, accessibility and long-term maintainability.

• TypeScript
• React 19
• Next.js
• NestJS
• Node.js
• Zustand
• React Query
• Tailwind CSS
• Prisma
• PostgreSQL
• Redis
• WebSockets (Socket.IO)
• MercadoPago
• Turborepo
• Vitest/Playwright
• Vercel