Status AVAILABLE
Role Senior Frontend · UI Designer
Location Concordia, AR
Timezone UTC−3 · AR

JUAN LANGE — Senior Frontend Developer & UI Specialist

ENGINEERING_FLOW
PRODUCTION_READY
NETWORK LATENCY
Z:−0300 UTC
NODE:SR_FRONTEND_01
SIG:ACTIVE · REMOTE

PROFILE_SPEC // v2026

Senior Front-End Developer with a design core.

20+ years of experience designing and building modern web applications across UI systems, frontend architecture, and full-stack development. I now use Spec-Driven Development, AI-assisted workflows, and automated testing to deliver software faster and with greater confidence.

Philosophy
Craftsmanship • Performance • Scalability
Years of Experience
20+
Delivery
Specification → Development → Delivery
DESIGN
UI Systems
Design systems that scale across products.
PRIMARY FOCUS
Frontend
High-performance interfaces built for real users.
SPECIALIZATION
Full Stack
From UI implementation to backend architecture.
ENGINEERING
Code Quality
Reliable, tested and production-ready software.
AI DEVELOPMENT
Spec-Driven
AI-assisted development powered by clear specifications.

STACK // MATRIX

Total cells23
Active23
Styles
CSS3
Animation
GSAP
Markup
HTML5
Language
JavaScript
Framework
Next.js
Testing
Playwright
Library
React
State
Redux
Styling
Tailwind
3D
Three.js
Language
TypeScript
State
Zustand
Auth
Auth.js
API
Express
Database
MongoDB
Database
MySQL
Runtime
Node.js
Database
PostgreSQL
ORM
Prisma
ORM
Sequelize
Design
Figma
Workflow
Git · GitHub
Agile
Scrum

PORTFOLIO // SELECTED WORKS

Next.js 15 TypeScript Prisma Playwright
QA_LAB
A personal learning project built while studying QA Automation. QA Lab centralizes test cases, executions, reports, and quality metrics into a single platform. It ingests real Playwright JSON reports, processes them through an ETL pipeline, and visualizes actionable quality metrics with historical tracking.
TypeFull-Stack
StackNext.js + Prisma + SQLite
StatusLive
View Project ↗
QA Lab
React TypeScript Three.js Zustand Vite
PLANNER_3D
A commercial demo developed with Dinamo Studio. Visual proposal builder that composes real playground equipment into a 3D site plan, with physical dimensions, capacities, age ranges, metric grids, and computed safety areas that surface spatial conflicts before review. Includes autosave and PDF export.
TypeClient
StackReact + Three.js + Zustand
StatusLive Demo
View Project ↗
Planner 3D
React Three.js Vite
RASTI_LAB
A conceptual demo of a digital Rasti model constructor. Built as a personal project to explore 3D interaction and WebGL in the browser. Features a playful kids-themed boot loader and an immersive 3D building experience.
TypePersonal
StackReact + Three.js + Vite
StatusIn Progress
View Project ↗
Rasti Lab
React Tailwind CSS GSAP NASA API
HUBBLE_PROJECT
A personal project where I practice new development and animation techniques. Fully designed and developed by me, from visual identity and UI/UX structure to front-end implementation. Integrates images and videos from NASA's API.
TypePersonal
StackReact + GSAP
StatusLive / In Progress
View Project ↗
Hubble Project
HTML CSS JavaScript GSAP
PORTFOLIO V01
Personal portfolio showcasing 25+ years of UI design and frontend development experience. Brutalist technical aesthetic with scroll-driven animations, interactive HUD widget, and a career timeline spanning Argentina, Spain, and the U.S.
TypePortfolio
StackHTML + GSAP + Three.js
StatusLive
View Project ↗
lange.com.ar Portfolio
UI/UX Design React Next.js
TERO
UI redesign for Tero, an open-source framework for building and running AI agents connected to real tools, systems, and organizational data. Enables prototyping and deploying agents that automate tasks and integrate with existing workflows.
TypeRedesign
StackReact + Next.js
StatusLive
View Project ↗
Tero UI Redesign
Branding Identity Design
R20
R20 is a radio code used by firefighters to indicate a "wildfire." A branding project as tribute to the brigades who worked during the 2025 Valle Magdalena fire in Argentina. A clothing brand concept that captures the spirit, purpose, and resilience of the brigadistas.
TypeBranding
Year2025
FocusIdentity
R20 Branding

Let's build something that works beautifully.

EXPERIENCE // TIMELINE

2023-PRESENT
Freelance Software Developer
Freelance · Concordia, Argentina
Building modern, mobile-first websites and interfaces for small businesses and entrepreneurs. Delivering end-to-end solutions from concept to deployment. Applying React, Next.js, and Tailwind CSS where project scope allows. Collaborating directly with clients, managing requirements, timelines, and delivery.
2021-2023
Frontend Web Developer
Latitur · San Martín de los Andes, Argentina
Led a full UI revamp of a large-scale tourism platform, improving visual consistency and maintainability. Re-structured legacy CSS and styling systems across multiple technologies. Worked with Angular-based CMS and built standalone React components for content management and front-facing features.
2009-2022
Creative Director
Estudio 22 · Remote
Delivered custom websites and web applications for clients and studios in the U.S. and Spain. Specialized in front-end development and UI design, balancing technical requirements with visual quality. Built and maintained WordPress-based solutions and custom PHP/MySQL projects.
2008-2020
Freelance - UI/Flash Developer
Creativat · Tarragona, Spain
Specialized in Macromedia Flash development and UI design. Transitioned exclusively to UI design as Flash declined. Participated in branding development across several projects.
2011-2012
Design & Development
Nexion Solutions · Buenos Aires, Argentina
Led front-end development for a media project serving a major TV network in Ecuador. Coordinated a small development team and acted as main technical contact with the client.
2005-2008
Owner / Partner - Creative Director
Le Mot · San Martín de los Andes, Argentina
Partner and co-owner, led the creative department. Worked for clients including Aerolíneas Argentinas, Movistar, NeuquenTur, Gabriel Batistuta, Cerro Caviahue, Cerro La Hoya, and Vía Bariloche.
2004-2005
Design / Development
Interpatagonia S.A · Argentina
Worked in the Design and Programming Department, contributing to interpatagonia.com and welcomeargentina.com portals, and developing websites for clients.
2001-2002
Instructor - Flash & Dreamweaver
Image Campus · Argentina
Worked as an instructor in Macromedia Flash and Dreamweaver tools (formerly Macromedia, now Adobe).
1999-2002
Coordinator / Speaker
Multimedia User Group de Argentina
Co-Founder and Coordinator of the Macromedia User Group of Argentina, a community that grew to over 9,000 members. Extensive experience as a speaker and presenter at seminars on Web Design and Technology.

CONTACT // SIGNAL_CHANNELS

LinkedIn linkedin.com/in/juancarloslange
GitHub github.com/juanlange
Email juancarloslange@gmail.com