Santiago M.

Full-Stack Engineer & Product Builder · Agentic AI Development (Claude, Cursor, etc) · LLM Integration (APIs)

Buenos Aires, Buenos Aires Province, Argentina

About

Full-stack engineer with 15+ years shipping end-to-end products across fintech, crypto, and consumer apps. I work best in high-autonomy environments: translating a founder's vision into scoped technical plans, making architecture decisions independently. I run an AI-native development workflow — Claude Code and Cursor for agentic coding, spec-driven development, and AI-generated test suites — which lets me ship production-grade MVPs solo at the pace of a small team. I also build with LLMs directly: API integration (Anthropic/OpenAI/Gemini), structured outputs, and rapid prototyping of AI-powered features.. I've taken products from zero to production with full ownership over architecture, delivery, and business outcomes — from technical decisions through deployment, SEO, and monetization. I've operated as the most senior technical voice in lean startup teams, owned integrations with financial infrastructure (PIX, blockchain, BaaS providers), and driven product strategy directly with founders. If the goal is to go from idea to shipped product quickly, I thrive in that environment. SKILLS Backend: Python · FastAPI · Django · Celery · Kafka · Event-driven architecture · REST APIs Frontend: React.js · JavaScript · TypeScript Mobile: Android Native (Java) Infra & Delivery: PostgreSQL · Docker · Kubernetes · AWS · Heroku · CI/CD · TDD Fintech: PIX integration · BaaS provider APIs · Cross-border payments · Payment reconciliation · Blockchain/Bitcoin Product: 0→1 product ownership · MVP scoping · Architecture decisions · Direct founder collaboration · SEO · Monetization AI Engineering: LLM API integration (Anthropic, OpenAI) · Prompt engineering & structured outputs · RAG prototyping · ML pipelines · Pandas · NumPy AI-Native Workflow: Agentic coding (Claude Code, Cursor) · Spec-driven development · AI code review & verification · MCP

Experience

  • Software Engineer — Cross-border Payments Platform (1→100) at kamiPay
    Dec 2024 - Present · 1 yr 7 mos

    Architected event-driven payment processing systems using Python/FastAPI and a message streaming architecture. Led end-to-end integration of PIX (Brazil's instant payment network) and third-party financial APIs — owning architecture design, implementation, and transaction processing logic. Designed and built backend systems for multi-currency payment workflows, improving settlement reliability and reducing manual intervention in transaction processing. Operated as the most senior engineer by tenure, making independent architecture decisions and driving technical strategy in a lean team with high autonomy. Designed a data-informed rate-limiting and traffic management architecture to improve system resilience under high-load payment scenarios. Architected an automated exception triage engine using Anthropic's API to resolve complex payment reconciliation discrepancies via structured tool-calling.

  • Software Engineer — Real Estate Tech at Stealth Startup
    Jun 2021 - Sep 2024 · 3 yrs 4 mos

    Owned the full-stack architecture and delivery of property management web applications — Python/Django, React.js, PostgreSQL — from requirements to production. Drove architecture decisions for scalable, multi-stakeholder workflows (clients, agents, operations), balancing rapid delivery with long-term maintainability. Led cross-functional collaboration across product, design, and business teams, translating ambiguous strategic goals into scoped technical plans and shipped features. Delivered performance optimizations and infrastructure improvements that meaningfully reduced latency and improved system reliability.

  • Full Stack Engineer & Data Engineer — Algorithmic Trading (0→1) at Tradi
    Apr 2017 - Jun 2021 · 4 yrs 3 mos

    Architected and built microservices interfacing with live crypto markets in real-time, processing streaming data to feed analytical and trading models. Designed and owned a trading algorithm performance analytics platform: monitoring dashboards, control mechanisms, and optimization feedback loops. Owned backend architecture (Python, Django, Celery, async), data pipelines (Pandas, NumPy), and deployment (Kubernetes, CI/CD) in a fintech environment demanding high reliability.

  • Founder & Mobile Engineer — Android App (0→1) at LectorApp
    Jul 2015 - Jul 2017 · 2 yrs 1 mo

    Owned concept-to-production delivery of a news aggregator Android app — 5,000+ downloads on Google Play. Clean Architecture, RxJava, Firebase Analytics, AdMob monetization. Full technical accountability across the stack: Android native app + Python/Django REST API backend, Heroku deployment, CI with Travis, crash reporting, and remote config via Firebase.

  • Full Stack Engineer — Fintech / Blockchain at Ripio
    Oct 2014 - Feb 2017 · 2 yrs 5 mos

    Led development of the Ripio Bitcoin Wallet for Android at one of Latin America's leading crypto exchanges — owned architecture, features, and security implementation. Built and maintained critical backend features with Python/Django for blockchain integrations, wallet operations, and exchange APIs. Spearheaded development of an automated identity verification system using Python and ML, reducing manual review while improving onboarding security.