Wilber Ulloa

Senior Frontend Engineer

React · Next.js · TypeScript

AI-Powered Products

wuj890312@gmail.com ·Whatsapp·LinkedIn

Senior Frontend Engineer with 8+ years building web products for enterprise clients including Walmart, DoorDash and UberEats. Specialises in React, Next.js and TypeScript. Most recently delivered AI agent infrastructure at Woflow: MCP integrations, an agent configuration wizard and a human-in-the-loop data pipeline at enterprise scale.

Beyond the code

Away from the keyboard I'm usually chasing the perfect espresso — slowly turning a coffee obsession into proper barista skills, one latte-art pour at a time. I'm a huge sports fan: baseball above all (die-hard New York Yankees supporter, still dreaming of a seat at Yankee Stadium) and football, with Real Madrid in my heart. And I don't just watch from the couch — working out and keeping a healthy life are part of the routine.

Seville, Spain

wuj890312@gmail.com ·Whatsapp·LinkedIn

years building web products

200k+

users served on a single product

85%+

test coverage maintained

Shipped for

Walmart · DoorDash · UberEats · Square · Lightspeed

Experience

Nov 2022 – Apr 2026 (3 yrs 6 mos) · San Francisco, CA, USA (Remote)
Senior Fullstack Engineer · Woflow Inc
Built the customer-facing AI agent platform — MCP tool integrations, a no-code agent wizard and a human-in-the-loop data pipeline for Walmart.
React · Next.js · TypeScript · Ruby on Rails · Supabase · Tailwind CSS · LangGraph · LangChain · MCP
Apr 2017 – Oct 2022 (5 yrs 7 mos) · Remote
Frontend Developer · Fonoma LLC
Led the full AngularJS-to-React migration and the shared component library behind a product serving 200,000+ users.
React · Next.js · TypeScript · Python · Django · styled-components · Jest · React Testing Library
2021 – 2022 · Remote
Frontend Developer · Self-employed (Freelance)
Shipped a full e-commerce platform solo in under 8 weeks, alongside cross-platform apps in Ionic and Flutter.
React · Next.js · TypeScript · Ionic · Angular · Flutter
May 2016 – Aug 2017 · Remote
Software Engineer · Copsonic
Built native Android apps for ultrasound-based device communication on the CopSonic SDK.
Java · Android SDK · JavaScript

Skills

React
Next.js
TypeScript
JavaScript (ES6+)
Tailwind CSS
styled-components
Redux
Material UI
HTML5
CSS3
SASS

Education

2023 · Seville, Spain
Master's — Web Design & Development
CEI Centro de Estudios de Innovación
2008 - 2013 · Havana, Cuba
Engineer's Degree — Automation & Software Design
Instituto Superior Politécnico José Antonio Echeverría

Languages

Spanish
Native
English
C1 · Advanced

Open to Senior Frontend Engineer roles

Remote, or hybrid in Europe · Based in Seville, Spain

Get in touch Download CV

Senior Frontend Engineer / React / Next.js / TypeScript / AI-Powered Products

Seville, Spain
+34 695 135 544
wuj890312@gmail.com
linkedin.com/in/wilber-ulloa-jorge-868960a0

Professional Summary

Senior Frontend Engineer with 8+ years of experience building high-quality web products — from fast-moving startups to platforms serving enterprise clients including Walmart, DoorDash, UberEats, Square, and Lightspeed. Specialises in React, Next.js, and TypeScript, with deep experience in component architecture, performance optimisation, and test-driven development. Comfortable contributing across the full stack (Ruby on Rails, Python/Django, Supabase) while keeping frontend quality as the primary craft. Most recently delivered customer-facing AI agent infrastructure at Woflow: MCP tool integrations, an agent configuration wizard, a version-control system for agent snapshots, and a human-in-the-loop data ingestion pipeline at enterprise scale. Proven in remote, cross-functional teams and open to Senior Frontend Engineer roles — remote or hybrid in Europe.

Technical Skills

Frontend: React, Next.js, TypeScript, JavaScript (ES6+), Tailwind CSS, styled-components, Redux, Material UI, HTML5, CSS3, SASS
Testing: Jest, React Testing Library, Storybook
Backend: Node.js, Ruby on Rails, Python, Django, FastAPI, REST APIs, Supabase, Google App Engine
AI & Agents: LangGraph, LangChain, MCP (Model Context Protocol), RAG, Claude Code, Prompt engineering
Mobile: React Native, Flutter, Ionic
Tools & Methods: Git, GitHub, CI/CD, Docker, Figma, Agile/Scrum

Professional Experience

Senior Fullstack Engineer · Woflow Inc · San Francisco, CA, USA (Remote)

· Nov 2022 – Apr 2026 (3 yrs 6 mos)

Woflow automates structured data operations for enterprise clients including Walmart, DoorDash, UberEats, Square, and Lightspeed.

Contributed to the company's customer-facing AI agent platform, implementing an MCP-based tool integration layer that exposed capabilities to AI agents, and a configuration wizard enabling clients to build and deploy agents without engineering support.

Designed and implemented an agent versioning system introducing snapshot-based version control — allowing users to compare agent performance across draft, published, and historical versions with different tools, knowledge bases, and skills. Previously, agents had no version history.

Built a human-in-the-loop data ingestion pipeline for Walmart: a fullstack feature enabling operators to upload large retail CSVs, parse them into products and sub-products, review structured output, and trigger agent ingestion — handling high-volume catalog data at enterprise scale.

Maintained and extended Ruby on Rails backend services, navigating a complex monolith across models, controllers, and API layers — owning cross-layer features end-to-end without handoff.

Led engineering support for legacy XtremeAI clients post-acquisition, maintaining platform stability and resolving critical issues during migration.

Collaborated within a cross-functional team of 10–20 engineers to deliver scalable solutions across frontend and backend.

Stack: React · Next.js · TypeScript · Ruby on Rails · Supabase · Tailwind CSS · LangGraph · LangChain · MCP

Frontend Developer · Fonoma LLC · Remote

· Apr 2017 – Oct 2022 (5 yrs 7 mos)

Fonoma is a telecom-focused SaaS product with 200,000+ users, delivered by a lean frontend team of fewer than 5 developers.

Led the full AngularJS-to-React migration across the entire client codebase — modernising architecture under continuous production constraints with no downtime.

Built and maintained the shared React/Next.js component library powering the full product UI/UX surface for 200,000+ users, as part of a frontend team of fewer than 5.

Established and maintained test coverage above 85% using Jest and React Testing Library across 5+ years of continuous delivery.

Contributed to backend REST API development using Python and Django on Google App Engine.

Stack: React · Next.js · TypeScript · Python · Django · styled-components · Jest · React Testing Library

Frontend Developer · Self-employed (Freelance) · Remote

· 2021 – 2022

Delivered a full e-commerce platform using React, TypeScript, Next.js, NextAuth, and Material UI — solo, in under 8 weeks.

Built two cross-platform Ionic/Angular 12 applications for American Iron & Metal (AIM): one for managing auto parts sales and one for tracking vehicle catalysts across physical warehouse locations.

Developed and maintained mobile application features for Aerial using Flutter (Dart).

Stack: React · Next.js · TypeScript · Ionic · Angular · Flutter

Software Engineer · Copsonic · Remote

· May 2016 – Aug 2017

Built SonicQRCode, a native Android application enabling ultrasound-based communication between mobile devices and web components using the CopSonic SDK.

Developed Nikon 360 Viewer, a native Android app for displaying 360° video content from Nikon's 360-degree camera hardware.

Built additional Android SDK demo applications for testing CopSonic on mobile and wearable devices.

Stack: Java · Android SDK · JavaScript

Education

Master's — Web Design & Development Seville, Spain

CEI Centro de Estudios de Innovación · 2023

Focus: HTML5, CSS3, MERN stack (MongoDB, Express, React, Node.js)

Engineer's Degree — Automation & Software Design Havana, Cuba

Instituto Superior Politécnico José Antonio Echeverría · 2008 - 2013

Languages

Spanish · Native

English · C1 · Advanced