Senior Software AI Engineer

Jairo Gätjens

Senior Software Engineer with 15+ years of experience building scalable web applications and leading frontend initiatives. Specialized in React, Next.js, TypeScript and Node.js, with experience across frontend architecture, APIs, design systems, headless platforms and AI-powered product features.

available for new opportunities
Remote, Costa Ricajgatjens@gmail.com
View Projects →LinkedIn ↗

Frontend Engineering

React, Next.js, TypeScript, JavaScript, React Native, Ionic

Full-Stack Development

Node.js, APIs, PostgreSQL, MySQL, MongoDB

Architecture & Design Systems

Scalable UI, Design systems, SSR/SSG, Headless platforms

AI & Modern Development

AI integration, AI-powered applications

Professional Experience

Work history

A selection of my professional experience building web applications, leading frontend initiatives and working with modern technologies across different industries.

Select a role to see responsibilities, technologies and additional details.

Key Responsibilities

  • Develop and enhance a CRM platform with a strong focus on frontend engineering, user experience, and modern web application architecture.
  • Build scalable and maintainable frontend features using React, Redux, and RxJS, implementing reactive - programming patterns and efficient state management solutions.
  • Design and develop reusable UI components, improving application consistency, performance, and maintainability.
  • Implement new product features and user-facing functionality based on business requirements and customer needs.
  • Integrate and develop AI-powered features to enhance application capabilities, automate workflows, and improve user productivity.
  • Collaborate with product teams, designers, and engineers to deliver intuitive, high-quality user experiences. Optimize frontend performance, troubleshoot complex UI issues, and improve application reliability.
  • Contribute to frontend architecture decisions, code quality improvements, and best development practices. Work with backend services built on .NET by creating integrations, consuming APIs, and supporting end to end application functionality.
  • Participate in the complete software development lifecycle, including planning, development, testing, deployment, and continuous improvement.

Technologies

ReactReduxRxJS.NETAI

Key Responsibilities

  • Worked with senior engineers and product teams to build scalable, user-centric applications.
  • Responsible for creating demos and full products for clients.
  • Create Figma prototypes.
  • Integration with sitecore xp and xmcloud sites.
  • integration with microsoft sharepoint.
  • Ionic Apps.
  • Create design systems for backend integration.
  • React, Next.js, Storybook, Nodejs.
  • PC and macOS environments.

Technologies

ReactNext.jsStorybookNode.jsSitecore XM CloudIonic

Key Responsibilities

  • Career developer
  • Work on ni.com projects
  • Create unit tests for ni.com projects
  • Custom storybook components (angular and vanilla javascript)
  • Create a small design system for hangarworldwide.com
  • Create programs for people level skills
  • Talk directly with clients
  • Responsible for creating demos for clients
  • Follow Agile methodologies (Azure)
  • Create Figma prototypes
  • Help with ni.com design system

Technologies

AngularStorybookJavaScriptFigma

Key Responsibilities

  • Work on OrTracker React native app, Web App, and Node API.
  • Work for mergeworld.com.
  • Create multiple static and dynamic WordPress sites.
  • Create style guides for multiple sites.
  • Create SPA using react and angular.
  • Migrate www.wunderground.com to angular
  • Work with multiple APIs
  • Server side rendering with Expressjs
  • Unit test with jasmine
  • Use of Agile methodology (Jira)
  • D3 and D3 server side rendering
  • Foundation

Technologies

React NativeReactAngularNode.jsExpress.jsD3

Key Responsibilities

  • Generated a methodology for Code Reviews at least once a month within the Front–end department.
  • Fostered an environment to lunch and learn at least once a month
  • Acted as a leader in terms of technology. Manage deliverables, raise flags (risks), and ensure that the projects cames on time and in compliance with the estimate.
  • Scheduled and conducted one on one at least every 15 days with all my team members.
  • Created tasks for people who were available.
  • Collaborated with the Technology Directors, Project Managers, Creative Leads, and Account leads to design, develop and deliver digital marketing projects on mobile, web, and desktop platforms.
  • Functioned as a leader and coordinator of the Application Developers, Web Developers, and Database Developers.
  • Ensured successful involvement of Project Management, Quality Assurance, and Release Engineering team members.
  • Assisted on the architecture and development of multiple projects.

Technologies

Visual Basic 6.0C#

Key Responsibilities

  • Designed Web-based (Java/JSP) Internet applications linked to Oracle databases.
  • Analyzed business, functional, and technical requirements.
  • Technical Support.
  • IT tasks like windows updates, windows problems, new installations, users' specific requests, etc...

Technologies

JavaJSPOracle

Technical Skills

Engineering stack

A combination of modern frontend, backend and cloud technologies I use to build scalable applications, design systems and AI-powered solutions.

Focused on creating maintainable, accessible and high-quality applications using modern frameworks, best practices and AI-assisted development.

Core Engineering Stack

React

Web & mobile UI

N

Next.js

SSR / SSG / App Router

TS

TypeScript

Type-safe development

Node.js

APIs & services

PostgreSQL

Relational database

REST / GraphQL

APIs & integrations

Frontend & State

Frameworks, libraries and patterns for modern web and mobile applications.

  • React
  • Next.js
  • React Native
  • Ionic
  • Angular
  • Redux
  • Jotai
  • React Query
  • SWR
  • RxJS

Backend & Data

Server-side development, APIs and databases.

  • Node.js
  • .NET
  • GraphQL
  • REST APIs
  • PostgreSQL
  • MySQL
  • MongoDB

Architecture & Platforms

Scalable architectures, headless platforms and modern Next.js features.

  • SSR / SSG
  • Server Components
  • NextAuth
  • i18n
  • Sitecore XM Cloud
  • Contentful
  • Strapi

Design Systems & UI

Component libraries and styling tools to build consistent and accessible user experiences.

  • Storybook
  • Tailwind CSS
  • Radix UI
  • Shadcn UI
  • Chakra UI
  • Styled Components
  • Sass / SCSS
  • CSS Modules
  • BEM
  • Less

AI & Modern Development

AI integration and tools to accelerate development and build AI-powered features.

  • AI integration
  • AI-powered applications
  • Workflow automation
  • AI-assisted development

Tooling & Quality

Build tools, testing, accessibility and design tools.

  • Vite
  • Webpack
  • Gulp
  • Grunt
  • Docker
  • WCAG AA
  • SEO
  • Figma
  • Adobe XD
  • Sketch
  • Photoshop

Education & More

Education

Formal education and continuous learning have given me a strong foundation in computer science and engineering, which I continue to expand through new technologies and languages.

I'm a lifelong learner, always exploring new technologies, frameworks and languages to improve as an engineer and build better products.

Formal Education

2005 – 2008

Universidad Fidélitas, Costa Rica

Bachelor's in Computer Science

2011 – 2012

Universidad Latina, Costa Rica

Electrical and Electronics Engineering

Languages & Learning

Italian

Currently learning

Learning

Japanese

Currently learning

Learning

English

Working language

Professional

Spanish

Native language

Native

Continuous Learning

Always learning

Always exploring new technologies, tools and languages to grow as an engineer and contribute to better products and experiences.

let's work together

have a project in mind?

let's build something great together.

available for new opportunities
remote · costa rica
let's talk →
Email me ↗LinkedIn ↗View Resume ↗

let's build something great together.