Matías Fernández

SELECTED ENGINEERING WORK

Systems I have
helped make real.

Four projects chosen for the decisions, responsibility, and evidence behind them. Public work links to source and tests; private and client work uses explicit disclosure boundaries.

01

2024 — NOW

Published case study

Enterprise AI Platform

Frontend lead · hands-on across the stack

An Azure OpenAI product for an enterprise healthcare client. I lead its React and Next.js frontend and contribute targeted work across document processing, retrieval, streaming, .NET, and Azure Functions.

Evidence
1,000+ documents through the pipeline · sub-2s time-to-first-token target
Selected stack
React · Next.js · Azure OpenAI · Pinecone · SignalR · .NET
Read the case study
02

PUBLIC REPOSITORY

Published case study

AI Knowledge Platform

Sole author · product and engineering

A document knowledge platform where retrieval quality, honest failure states, and verifiable citations are product surfaces. Milestones 1–3 are accepted; grounded answers are implemented and await live-provider acceptance.

Evidence
3 / 5 milestones accepted · Recall@3 and MRR@3 enforced in CI
Selected stack
Python · FastAPI · Next.js · TypeScript · SQLite FTS5 · OpenAI Responses API
Read the case study
03

2026 · FUNCTIONAL MVP

Published case study

PsiNota

Sole author · product design, architecture, and full-stack engineering

A mobile-first, offline-first product that turns mental-health consultation audio into an editable clinical-note draft. It combines resilient capture, asynchronous AI processing, human review, versioning, and audit history.

Evidence
7 / 7 tests passing · API, web, and service-worker production builds verified
Selected stack
React 19 · TypeScript · Express · PostgreSQL · TypeORM · OpenAI · PWA · Docker
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04

2019 — 2021

Published case study

Serverless Platform Modernization

Full-Stack Engineer · shared technical coordination

An Angular 7-to-12 modernization and a move from Java services to Node.js and TypeScript serverless services on AWS. I shared coordination of the UI work with two other developers.

Evidence
Team migration reduced infrastructure cost by ≈ 30%
Selected stack
Angular · Node.js · TypeScript · AWS Lambda · DynamoDB · Terraform
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OPEN TO SENIOR AND LEAD ENGINEERING ROLES

Discuss a role