Mitzael Serna

Senior Software Engineer and Full-Stack ML Engineer / Tech Lead open to global remote roles, with 14+ years of experience architecting and building scalable web applications, microservices, AI-powered platforms, and robust backend systems across diverse technology stacks and programming languages.

Proven versatility in full-stack development and machine learning, having successfully delivered projects using multiple languages (Python, Ruby, JavaScript, TypeScript, C#, PHP, Elixir, Java) and frameworks (Ruby on Rails, .NET, Node.js, FastAPI, PyTorch, React.js, Vue.js) across various industries and use cases.

Currently building production AI systems with computer vision pipelines, LLM integration, and microservices architecture.

Continuously adapts to and adopts emerging technologies, with a track record of quickly mastering new languages and frameworks to deliver innovative solutions.

Experienced in leading cross-functional teams, designing distributed systems, and optimizing high-traffic applications handling 1M+ requests monthly.

Expert in AI-assisted development workflows, machine learning infrastructure, and modern DevOps practices.

• Tech lead for AI-native products and customer platforms: conversational AI, humanized support experiences, intelligent automation, and real-time integrations.
• Hands-on across architecture, backend, frontend, infrastructure, and AI-driven product development.
• Stack includes Ruby on Rails 7.1 / Ruby 3.4, PostgreSQL, pgvector, Redis, Sidekiq, OpenSearch, Vue 3, Vite, Pinia, Tailwind CSS, JWT and role-based permissions.
• Integrations: AWS, Azure, and GCP storage; Stripe, Twilio, Slack, and push notification systems.

• Designed and implemented microservices architecture with 12+ ML services using FastAPI, PyTorch, and CUDA for GPU acceleration on AWS EC2 with NVIDIA instances.
• Built API Gateway and orchestration layer (Express.js/TypeScript) coordinating multi-model inference pipelines for real-time biometric analysis.
• Deployed production computer vision models including YOLOv8, EfficientNet-B0, ResNet, and Faster R-CNN for image classification and object detection.
• Integrated Google Gemini LLM for automated narrative generation from structured analysis data, enabling personalized content creation.
• Developed modern React 18 SPA with TypeScript, Material UI, Redux Toolkit, and Framer Motion, implementing real-time features using Socket.io.
• Built image preprocessing pipelines using OpenCV, MediaPipe, and dlib for facial landmark detection and biometric feature extraction.
• Reduced TTS service memory footprint from ~800MB to ~50MB by migrating to edge-based solution, optimizing infrastructure costs.
• Containerized 15+ services with Docker and Docker Compose with optimized multi-stage builds for consistent deployments.
• Implemented Stripe payment system handling subscriptions, credits, and usage tracking for SaaS billing model.
• Built end-to-end pipeline processing 5 image types (frontal, profile, body, palms, eyes) in single request for comprehensive analysis.

• Promoted to Tech Lead (Jan 2025); led Acumatica team—microservice connector syncing Paystand payments to Acumatica ERP and syncing invoices, sales orders, and customers via push notifications and custom projects.
• Contributed to 2.0 ERP sync architecture for Acumatica and other ERPs (NetSuite, Sage Intacct) using Temporal and Node.js.
• Built proxy microservice in Elixir to authorize requests to any ERP, resolving credentials on incoming traffic.
• Architected and developed microservice connecting with Acumatica's custom Extended API, enabling bidirectional data synchronization for Payments, Invoices, Sales Orders, Refunds, Fees, Transfer Funds, and Disputes.
• Created custom Acumatica project implementing Extended API endpoints, Push Notifications, Generic Inquiries, and Custom Email Templates, reducing integration complexity and improving workflow efficiency.
• Resolved critical integration challenges including rate limiting issues and continuous integration complexities with Acumatica's platform, ensuring system reliability and performance.
• Improved development delivery velocity by implementing AI-assisted workflows: internal GPTs, Cursor automation rules, and agent notepads using MCPs.
• Worked across multiple programming languages and technology stacks (Elixir, TypeScript, JavaScript) within the same organization, demonstrating versatility and ability to adapt to project requirements and technology choices.
• Designed and implemented microservices architecture in Elixir/Phoenix to optimize internal processes, demonstrating adaptability by mastering functional programming paradigms and improving system scalability and maintainability.
• Implemented event-driven architecture using Apache Kafka for asynchronous messaging and real-time data streaming between microservices, ensuring reliable and scalable inter-service communication.
• Maintained and expanded NetSuite integrations using TypeScript, ensuring data consistency across multiple ERP systems while working across different technology stacks.
• Integrated Stripe and other payment processors to enable secure transaction processing and payment gateway integrations.
• Built internal monitoring dashboards in Appsmith for proactive monitoring and incident reduction, improving system observability.
• Containerized services with Docker and managed PostgreSQL/MySQL databases, optimizing deployment processes and database performance.
• Collaborated across teams using GitLab and Jira in agile environments, ensuring efficient project delivery.

• Tech lead for no-code tools and AI solutions; delivered doctor payment system with NestJS and React (Vite).
• Architected and developed KYC (Know Your Customer) system using .NET with C# and Razor, JavaScript, MS SQL Server, and Azure infrastructure, demonstrating proficiency across multiple technology stacks and ensuring compliance and secure data processing.
• Built full-stack applications using Node.js, NestJS, React.js, and Vite, seamlessly transitioning between different technology ecosystems and integrating payment gateways (Stripe, NetPay, STP) for seamless transaction processing.
• Led adoption of No-Code tools and AI-assisted development workflows using Cursor IDE, improving team productivity and standardizing development processes.
• Designed and implemented agent notepad prompts to standardize flows and accelerate team productivity across cross-functional teams.
• Mentored and led cross-functional teams in building scalable, user-centric solutions, applying MCP approaches (Graph Knowledge & Sequential Thinking) for faster problem-solving.

• Developed high-performance communication system using Twilio to mask personal phone numbers for customer contact, handling approximately 1 million requests per month with 99.9% uptime.
• Integrated comprehensive Twilio-based solutions including WhatsApp, Voice, Emails, Flex for Cloud Call Centers, Twilio Studio, Twilio Functions, and WhatsApp Templates, enabling multi-channel customer communication.
• Built mobile-first web applications using PHP, Node.js, and Express, ensuring responsive design and optimal user experience across devices.
• Architected serverless APIs with Azure Functions and implemented caching strategies with Redis, reducing API response times and infrastructure costs.
• Designed and managed Azure infrastructure including MS SQL Server database, Redis, Azure Functions, Event Hub, API Manager, and Ingest Manager, ensuring scalable and reliable system architecture.
• Transitioned from full-time to hourly model (since 2024), maintaining high-quality deliverables while optimizing work structure.

• Evolved a student and operations platform from PHP 7, CodeIgniter, MySQL, jQuery, and Bootstrap toward a modern stack.
• Current PWA: Angular 19, Ionic 8, TypeScript, Capacitor 7 (Android/iOS), RxJS, SCSS, ESLint, Karma/Jasmine, Playwright.
• Backend: NestJS 10, Node.js, TypeORM, MySQL, JWT (Passport), Swagger, Axios, class-validator / class-transformer.
• Earlier delivery included Ionic PWA and NestJS migration path from legacy LAMP features (files, tasks, tests, student tracking).

• Built and maintained critical applications with custom PHP, MySQL, jQuery, IndexedDB, and LAMP deployments on AWS.
• MySQL administration, GitLab workflows, Docker containers, and Mattermost for team collaboration.
• Implemented database migrations and CI/CD automation using GitLab and Docker, reducing deployment time by 60% and improving release reliability.
• Developed and executed DevOps strategy for reliable production deployments, ensuring zero-downtime releases and improved system stability.

• TuuKuul Network (May 2016 – Oct 2019) — PHP (CodeIgniter), MySQL, Ionic, Angular, Android app, APIs, project management, and server administration; workgroups, Dropbox-like sharing, and academic papers with tag-based discovery.
• Prisco Desarrollos (Jul 2017 – Feb 2018) — Completed podiatry clinic franchise web app: PHP (CodeIgniter), MySQL, Vue.js (library integration).
• COTecnologías (Corporativo Operador de Tecnologías) (Oct 2015 – May 2016) — Lead web developer: planned, designed, and built a PHP (CodeIgniter) business intelligence web system for economic and operational management.
• Grafav SA de CV (Feb 2015 – Oct 2015) — Web applications in PHP and C# with MySQL and SQL Server.
• Dearrollo de Soluciones Tecnológicas SA de CV (Jul 2013 – Feb 2015) — Gasoline dispensary control systems; main control module in Java with RMI.
• CIAD (May 2012 – Apr 2013) — Web module for papers and thesis participation and NRS ranking for research staff.