Miguel is available for hire
Hire MiguelMiguel Duarte
Verified Expert in Engineering
JavaScript Developer
Lisbon, Portugal
Toptal member since October 24, 2016
Bio
Miguel is a hands-on full-stack and AI engineer who, as the founding CTO of Care&, built a healthcare platform from scratch into an AI-native product: a custom AI Scribe, patient-facing assistants, and agentic operations automation. On the executive team, he helped grow the business to 7-figure revenue while leading a small engineering team. He applies frontier AI across the business: engineering, QA, infrastructure costs, SEO, and ads, giving AI agents the feedback loops to iterate and ship.
Portfolio
Ludo.ai
AI Agents, Large Language Models (LLMs), Model Context Protocol (MCP)...
Care & Family Health
Amazon Web Services (AWS), Express.js, Redux, Docker, React, Node.js...
Kaja (via Toptal)
Java, AngularJS, PHP, Node.js, Google Maps, MongoDB
Experience
- JavaScript - 16 years
- Node.js - 11 years
- Artificial Intelligence (AI) - 9 years
- Amazon Web Services (AWS) - 9 years
- React - 9 years
- CTO - 8 years
- TypeScript - 3 years
- Large Language Models (LLMs) - 3 years
Preferred Environment
Amazon Web Services (AWS), JetBrains IDE, Git, MacOS, Claude Code, Google Cloud Platform (GCP)
The most amazing...
...project I've worked on is building an AI-native healthcare platform end-to-end, from the first line of code to the AI Scribe clinicians use every day.
Work Experience
Head of Engineering & Growth
2020 - PRESENT
Ludo.ai
- Owned engineering and growth for Ludo.ai, an AI game-creation platform used by hundreds of thousands of game developers and studios; worked part-time alongside a CTO role until July 2026 and full-time since August 2026.
- Built the entire product platform: game ideation, GDD editor, AI chat assistant, image generation and editing, sprite animation with motion transfer, 3D with auto-rigging, video, audio (SFX, music, and voice), tile and map editor, and team collaboration.
- Designed a multi-provider LLM layer (Claude via Vertex AI, Gemini, OpenAI, OpenRouter, and DeepSeek) with fallback chains and cost tracking, and a tool-calling coding agent that vibe-codes playable HTML5 games (Phaser, PixiJS, and Three.js) streamed live.
- Shipped a hosted MCP server (TypeScript, MCP SDK, and Hono) with 32 tools generated from the OpenAPI spec, listed in the official MCP Registry, and a public REST API; studios use them to automate thousands of asset generations a day.
- Architected the Node.js and Express back end (OpenAPI-first, MongoDB, Redis, and Socket.IO), orchestrating around 80 generative ML operations via a custom job queue with pre-charging and refunds, plus a credit economy and Stripe billing with atomic charging.
- Built the React 18 SPA (Vite, MUI, Socket.IO, Vitest) with browser-side creative tools: three.js 3D viewer with rig posing and GLB merging, fabric.js mask editor, sprite animator, GDD editor with PDF export, audio waveforms, PostHog, and Sentry.
- Run production on GCP (instance groups behind HTTPS load balancers, zero-downtime deploys, Cloud Run, Cloud Build) with around 2,800 tests sharded in CI, a drill-tested disaster-recovery vault, and security hardening (2FA, passkeys, and anti-abuse scoring).
- Led growth as an engineer by building the analytics console and data pipeline (Stripe, PostHog, Brevo, and Search Console), running lifecycle email campaigns with holdout tests, grading every experiment weekly against its metric, and recovering failed payments through dunning.
- Drove programmatic SEO and GEO (generative engine optimization) on a Next.js marketing site, getting Ludo cited in AI assistant answers and tracking those citations with custom monitoring tooling.
- Built a games ETL scraping 14+ sources (Steam, App Store, Google Play, itch.io, TikTok ads, and YouTube) into a normalized 1.5+ million game database for market research, with Tor/VPN rotation, stealth Puppeteer, and resumable crawls.
Technologies: AI Agents, Large Language Models (LLMs), Model Context Protocol (MCP), Claude API, Generative Artificial Intelligence (GenAI), OpenAI API, Gemini API, Prompt Engineering, Node.js, TypeScript, React, Express.js, MongoDB, Redis, OpenAPI, Google Cloud Platform (GCP), Socket.IO, Next.js, PostHog, Web Scraping, CI/CD Pipelines, Three.js, Search Engine Optimization (SEO), Growth Marketing, Stripe, Puppeteer, Claude, AI Integration, LLM Integration, Workflow Automation, Workflow Automation & System Integration, API Integration, Third-party APIs, Full-stack Development, Full-stack, Data Pipelines, Data Extraction, Tailwind CSS, OpenAI, Architecture, Database Architecture, Pipelines, Workflows, User Roles, User Interface (UI), User Experience (UX), Reports, Reporting, Data Processing, CSV, Web Applications, Document Parsing, AI Automation, AI Tools, Back-end Development, Front-end Development
CTO
2017 - PRESENT
Care & Family Health
- Architected and built the company's healthcare platform end-to-end as founding CTO, from the first commit to the system that runs every aspect of a multi-provider primary care practice: patient-facing apps, clinical tooling, and infrastructure.
- Led the platform's evolution into an AI-native product: a custom AI Scribe that drafts visit notes and summarizes charts, patient-facing AI assistants for intake and booking, and an AI inbox that routes and drafts replies to patient messages.
- Served on the executive team from inception, shaping product strategy and growth as the company scaled to seven-figure annual revenue.
- Ran an AI-first engineering and business practice, applying frontier models to development, QA, infrastructure cost optimization, and growth (SEO and ads), and giving AI agents the tools to iterate and verify their work (CI, infrastructure, and logging).
- Built agent-based automation for back-office operations such as user provisioning, scheduling, and administrative workflows, substantially reducing manual operational work.
- Hired, mentored, and led a small engineering team, owning technical direction, code quality, and delivery across all projects.
- Implemented security and privacy by design for sensitive health data (PHI), with encryption at rest and in transit across all components, in line with Canadian healthcare privacy requirements (PHIPA).
- Designed and operated the company's cloud infrastructure on AWS (ECS, S3, DynamoDB, SNS, and SQS) with Docker-based CI/CD, reliably serving 50,000+ patients while optimizing resource costs.
- Integrated dozens of third parties, including payments (Stripe), government health systems (OHIP, Ontario Ministry of Health), HL7 clinical data exchange, eFax, telephony (Twilio and Microsoft Teams), and AI providers (Anthropic, OpenAI, and Google).
- Implemented fully-featured telemedicine capability into the system, where patients can have video appointments with a practitioner.
Technologies: Amazon Web Services (AWS), Express.js, Redux, Docker, React, Node.js, TypeScript, Artificial Intelligence (AI), Large Language Models (LLMs), AI Agents, Claude API, OpenAI API, Amazon DynamoDB, Stripe, WebRTC, Linux, Sass, JSON, REST, Swagger, Twilio API, Prompt Engineering, Socket.IO, HL7, Firebase, Redis, Amazon Bedrock AgentCore, Vertex AI, WebSockets, Vite, Material UI, Amazon S3 (AWS S3), Amazon Simple Queue Service (SQS), Speech-to-Text (STT), Deepgram, Amazon Transcribe, Optical Character Recognition (OCR), Technical Leadership, Telemedicine, Electronic Health Records (EHR), HIPAA Compliance, CTO, Infrastructure, Hands-on Implementation, HIPAA, Healthcare, Security, Scaling, High Code Quality, Leadership, Code Review, Puppeteer, Claude, AI Integration, LLM Integration, Workflow Automation, Workflow Automation & System Integration, API Integration, Third-party APIs, Full-stack Development, Full-stack, Data Pipelines, Privacy, Playwright, Tailwind CSS, AWS Lambda, Healthcare Software, OpenAI, Architecture, Database Architecture, Workflows, Role-based Access Control (RBAC), User Roles, User Interface (UI), User Experience (UX), Reporting, Maps, Geolocation, Data Processing, CSV, Web Applications, Document Parsing, AI Automation, AI Tools, Back-end Development, Front-end Development
Full-stack Developer
2016 - 2017
Kaja (via Toptal)
- Developed an intelligent itinerary planner accounting for user preferences and point-of-interest properties (location, rating, category) using machine learning techniques such as spatial clustering and genetic algorithms.
- Built a recommender system for events based on the users' Facebook liked pages. The system further cross-referenced the Facebook data with Last.fm's API to discern musical tastes.
- Added i18n to the product (both static and dynamic elements) using Microsoft Azure's Cognitive Services for automatic cached content translation.
- Implemented a customized itinerary viewer with Google Maps.
- Developed custom map overlays and integrated with the Directions API with client-side caching.
- Handled the complete redesign/rebranding of the website.
Technologies: Java, AngularJS, PHP, Node.js, Google Maps, MongoDB
Invited Assistant Professor
2016 - 2016
Universidade Europeia (Laureate International Universities)
- Taught and handled the curricular unit databases given to first-year students majoring in game and app development.
- Taught and contributed to the curricular unit computer architecture given to first-year students majoring in computer science and computer science with management.
- Placed in the top 10% of faculty with regard to student satisfaction.
Technologies: Assembly, MySQL
Postdoctoral Researcher
2016 - 2016
Instituto de Telecomunicações
- Developed a novel technique to automatically synthesize neural-based control for robots with complex morphologies.
- Built a client-server application to interact with the V-REP robotics simulator via its API, enabling the parallel and distributed evaluation of robotic controllers.
- Published three peer-reviewed publications in evolutionary robotics.
- Won the Fraunhofer Portugal Challenge 2016 for my PhD research work.
Technologies: V-REP, Artificial Neural Networks (ANN), Evolutionary Computation, Java
Doctoral Researcher
2012 - 2016
University Institute of Lisbon (ISCTE-IUL)
- Developed a novel artificial intelligence approach for automatic synthesis of robotic control.
- Designed and developed the hardware, software, and artificial intelligence for a real-world swarm robotics system.
- Published 24 peer-reviewed publications in evolutionary robotics and AI.
- Maintained and improved a custom distributed computing system.
- Applied digital fabrication techniques for fast, iterative hardware design.
- Won a Paper of Excellence award (IEEE ICDL-EPIROB, 2012), was nominated for a Best Paper award (PPSN, 2016), and won a Best Robot Video award (AAAI Video Competition, 2016).
- Wrote my PhD thesis and won the "Fraunhofer Challenge" (Fraunhofer Portugal AICOS) and the "Best PhD Thesis in Robotics" award (Portuguese Robotics Society).
Technologies: Electronics, Robotics, Machine Learning, Artificial Neural Networks (ANN), Evolutionary Computation, Java, Artificial Intelligence (AI), Robot Operating System (ROS), C, OpenCV, R, Python, Eclipse IDE, Ggplot2, Eclipse
Teaching Assistant
2013 - 2015
University Institute of Lisbon (ISCTE-IUL)
- Taught the curricular unit: Introduction to Programming to first-year students majoring in computer science, computer science with management, and computer science with telecommunications.
- Taught the curricular unit: Object-Oriented Programming to first-year students majoring in computer science, computer science with management, and computer science with telecommunications.
- Organized multiple events at the university in collaboration with the local IEEE student branch.
Technologies: Object-oriented Programming (OOP), Java
Web Developer
2009 - 2012
PTWS Lda
- Developed custom full-stack eCommerce solutions based on open-source platforms.
- Created third-party payment gateways for multiple eCommerce platforms.
- Managed a small team of developers and coordinated client project deliveries.
- Installed, configured, and developed modules for web software (Joomla, PrestaShop, WHMCS, and more).
Technologies: CSS, HTML, JavaScript, PHP, PrestaShop, Windows, jQuery, RedBean ORM, ASP.NET, XML, Ajax, Adobe Photoshop, Adobe Illustrator
Experience
JBotEvolver
https://github.com/BioMachinesLab/jbotevolverJBotEvolver is a Java-based open-source and versatile simulation platform for education and research-driven experiments in evolutionary robotics (ER). JBotEvolver has been used in previous ER studies of our research group: in offline evolution to online evolution and learning, single to multi-robot systems, and in a number of undergraduate and graduate courses at the University Institute of Lisbon (ISCTE-IUL).
Conillon
https://github.com/BioMachinesLab/conillonConillon is a lightweight distributed computing platform. It allows Java-based tasks to be computed on a grid of computers with minimal effort and overhead. The necessary Java classes are loaded by worker nodes as needed.
A Sea of Robots
https://www.youtube.com/watch?v=JBrkszUnms8Won the "Best Robot Video" award at the annual video competition of the AAAI international conference. The video showcases a real-world swarm robotics system for which I designed and developed the hardware, the software, and the artificial intelligence controllers as part of my doctoral research.
Color Orbs
https://www.microsoft.com/en-us/p/color-orbs/9wzdncrdrhpfA game for Windows Phone that tests the player's memory and reaction speed. The player has to click colored spheres in the correct order and can also use power-ups to make the task easier. Color Orbs received the first prize in the Windows Phone App Code Camp competition.
Jhip8
https://github.com/miguelduarte42/Jhip8Jhip8 is a Chip-8 interpreter written in Java and was intended as a first experiment in the world of emulation. The project implements all the opcodes and features with the exception of sound, and it was a fun exercise in low-level programming and virtual machine internals.
Chip8JS
https://github.com/miguelduarte42/Chip8JSThis is a JavaScript port of my Jhip8 Chip-8 emulator that runs directly in the browser, using an HTML5 canvas for rendering. Porting the interpreter from Java to JavaScript was a fun exercise in translating low-level emulation logic across languages.
A working version can be found at the link below:
http://miguelduarte.pt/2012/07/09/chip-8-emulator-in-javascript/
A working version can be found at the link below:
http://miguelduarte.pt/2012/07/09/chip-8-emulator-in-javascript/
Moppy and Floppy Guitar
I adapted the open-source project Moppy to be able to play sound in multiple floppy drives using a MIDI keyboard as input. A later version allowed music to be played on the drives using a real guitar (see URL for videos).
Education
2012 - 2016
PhD in Computer Science
University Institute of Lisbon (ISCTE-IUL) - Lisbon, Portugal
2010 - 2012
Master's Degree in Computer Science
University Institute of Lisbon (ISCTE-IUL) - Lisbon, Portugal
2007 - 2010
Bachelor's Degree in Computer Science
University Institute of Lisbon (ISCTE-IUL) - Lisbon, Portugal
Skills
Libraries/APIs
Node.js, Stripe, OpenAPI, Twilio API, Google Maps, React, jQuery, Socket.IO, Three.js, Puppeteer, Playwright, OpenCV, Ggplot2, Claude API, OpenAI API, WebRTC
Tools
PrestaShop, Eclipse IDE, Claude, RedBean ORM, Git, Adobe Photoshop, Adobe Illustrator, Claude Code, Amazon Simple Queue Service (SQS), Amazon Transcribe
Languages
Java, CSS, HTML, SQL, JavaScript, PHP, Assembly, Sass, XML, C#, C, Prolog, R, Python, TypeScript
Frameworks
ASP.NET, Redux, Swagger, AngularJS, Express.js, Material UI, Next.js, Tailwind CSS
Paradigms
Object-oriented Programming (OOP), HIPAA Compliance, REST, Model Context Protocol (MCP), Search Engine Optimization (SEO), Role-based Access Control (RBAC)
Platforms
MacOS, Linux, Google Cloud Platform (GCP), Amazon Web Services (AWS), Windows, PostHog, Eclipse, Docker, Firebase, Vertex AI, AWS Lambda
Storage
JSON, Database Architecture, MySQL, Redis, Amazon S3 (AWS S3), Data Pipelines, MongoDB, Amazon DynamoDB, PostgreSQL
Industry Expertise
Healthcare
Other
Evolutionary Algorithms, Neural Networks, Robotics, Artificial Intelligence (AI), Large Language Models (LLMs), Technical Leadership, Web Scraping, CI/CD Pipelines, AI Integration, LLM Integration, Workflow Automation, Workflow Automation & System Integration, API Integration, Third-party APIs, Full-stack Development, Full-stack, Healthcare Software, OpenAI, Architecture, Pipelines, Data Processing, CSV, Web Applications, Back-end Development, Front-end Development, Ajax, Prompt Engineering, WebSockets, Telemedicine, Electronic Health Records (EHR), Generative Artificial Intelligence (GenAI), Gemini API, Growth Marketing, Data Extraction, Privacy, Workflows, User Roles, User Interface (UI), User Experience (UX), Reports, Reporting, Document Parsing, AI Automation, AI Tools, Evolutionary Computation, Artificial Neural Networks (ANN), V-REP, Machine Learning, Electronics, JetBrains IDE, Robot Operating System (ROS), AI Agents, HL7, Amazon Bedrock AgentCore, Vite, Speech-to-Text (STT), Deepgram, Optical Character Recognition (OCR), Algorithms, CTO, Infrastructure, Hands-on Implementation, HIPAA, Security, Scaling, High Code Quality, Leadership, Code Review, Maps, Geolocation
Collaboration That Works
How to Work with Toptal
Toptal matches you directly with global industry experts from our network in hours—not weeks or months.
1
Share your needs
Discuss your requirements and refine your scope in a call with a Toptal domain expert.
2
Choose your talent
Get a short list of expertly matched talent within 24 hours to review, interview, and choose from.
3
Start your risk-free talent trial
Work with your chosen talent on a trial basis for up to two weeks. Pay only if you decide to hire them.
Top talent is in high demand.
Start hiring