Senior Frontend Developer

Agustín
Mesas

6+ years delivering high-impact frontends at Avalith — from Argentina's leading digital wallet to Latin America's largest e-commerce platform. Specialized in React, Next.js, and React Native, building interfaces at scale that millions of people use daily.

6+ Years experience
15+ Projects shipped
3 Industries

Projects

16 total
01

Tasime

Personal project. Chrome extension that replaces the new tab with a full bookmark and notes manager — real-time sync across devices, pinning and organization, soft-delete with recycle bin, and active tabs view.

React 19TypeScriptViteTailwind CSS 4Supabasednd-kitVitestMSW
02

MODO

Leading digital wallet in Argentina. Built key payment flows — transfers, QR payments, and savings — handling high-concurrency transactions for millions of users.

ReactNext.jsTypeScriptTailwindAxiosJestTesting Library
03

Mercado Libre

Built the loyalty rewards program frontend for a major e-commerce platform, engineering complex state management for high performance under peak traffic loads.

Reactreact-routerReselectAxiosJestTesting Library
04

N5 NOW

Banking dashboard integrating real-time data from core systems across multiple financial institutions with complex data visualizations and end-to-end testing coverage.

Reactreact-routerreact-queryMaterial-UIAxiosJestTesting LibraryPlaywright
05

CLARO

Internal administrative system for mobile line lifecycle management, improving operator workflows.

Reactreact-routerReduxRedux-SagasJestPlaywright
06

Swiss Medical

Healthcare management app for medical records, appointments, and emergency services.

React NativeReduxRedux-SagasReact-NavigationStyled-ComponentsJestPlaywright
07

Grow with Jane

Social platform for plant enthusiasts to track plant growth and share progress with community members.

Reactreact-routerReduxRedux-SagasReselectAxiosJestTesting Library
08

BASF Agro

Commercial goal management system for sales ambassadors, tracking sales targets and visits.

ReactMaterializeHTML5HerokuJest
09

Paper Chef

Internal management platform for paper wholesale order and product administration.

React.jsReduxRedux-SagasReact-RouterStyled-ComponentsJestEnzymePlaywright
10

Viasano

Mobile application for healthcare members to manage personal data and temporary credentials.

React NativeReduxRedux-SagasJest
11

Llevox

Mobile app connecting clients with transport providers, featuring real-time tracking and efficient route management.

React NativeAWSEC2S3RDSREST APIJest
12

Trampoline

Theatrical platform featuring geolocation and secure payments.

ReactHTML5CSS3Jest
13

Fox Decoder

System for TV signal decoding and electronic program guide (EPG) schedule management.

React.jsReduxHTML5CSS3Jest
14

Qupro

Management system for client relations, sales, and invoicing.

PHPLaravelReactAWSHTML5CSS3BootstrapJest
15

Medicos Online

Telemedicine platform connecting doctors and patients with integrated consultation analytics.

React.jsReduxRedux-SagasMaterial UIReactstrapJestEnzyme
16

Domain Line

Marketplace for buying and selling web domains.

React.jsNode.jsExpressJest

Experience

Avalith

Senior Frontend Developer

Led frontend development across 15+ client projects serving millions of users in fintech, healthcare, and e-commerce. Working in cross-functional teams of 5–15 engineers under SCRUM methodology with 2-week sprint cycles in the React ecosystem — React.js, React Native, Next.js.

  • Built core payment flows for MODO, Argentina's leading digital wallet — transfers, QR payments, and savings using React, Next.js and TypeScript.
  • Developed the loyalty rewards frontend for MercadoLibre, Latin America's largest e-commerce platform, engineering complex state management with Reselect under peak traffic loads.
  • Delivered real-time banking dashboards for N5 NOW integrating core financial systems, with end-to-end Playwright testing and live data via react-query.
  • Contributed to React Native apps for Swiss Medical and Viasano serving thousands of daily active users.

Skills

Frontend
ReactNext.jsReact NativeTypeScriptJavaScriptHTML5CSS3
State Management
ReduxRedux-Sagasreact-queryReselect
Testing
JestTesting LibraryPlaywright
Tools & Infrastructure
GitAWSNode.jsREST APIs
Working style
  • SCRUM methodology
  • Cross-functional teamwork
  • Problem-solving and decision-making
  • Effective communication

Get in touch

Open to new opportunities, freelance projects, and interesting collaborations.

mesas.agustin.e@gmail.com