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

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

• 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).

• 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.

• 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.