Logo
Oscar – React, React Native, Next.js, experts in Lemon.io

Oscar

From El Salvador (UTC-6)

flag
Front-end Web DeveloperSenior
Mobile DeveloperMiddle
8 years of commercial experience
Entertainment
Fintech
Healthcare
Healthtech
Medtech
Real estate
Sports
CRM
Mobile apps
Lemon.io stats
2
projects done
1635
hours worked
Open
to new offers

Oscar – React, React Native, Next.js

Oscar previously worked in customer service, where he excelled at building strong connections with customers. Driven by a passion for technology, he transitioned to programming and now supports teams with his front-end skills, particularly in projects aimed at enhancing the healthcare industry. Additionally, Oscar has a keen interest in personal finance and has delivered several public speeches on managing income wisely.

Main technologies
React
4.5 years
React Native
4 years
Next.js
2 years
Typescript
3 years
Additional skills
Ruby on Rails
Drupal
HTML
SASS
Storybook
Jest
Apollo GraphQL
Styled-components
Redux
CSS
JavaScript
Tailwind CSS
Vite
Webpack
REST API
MySQL
Ready to start
ASAP
Direct hire
Potentially possible
Ready to get matched with vetted developers fast?
Let’s get started today!

Experience Highlights

Tech lead
Nov 2022 - Sep 20239 months
Project Overview

A newly launched finance tracking app that allows their users to plan their monthly income, expenses, savings and debt payments.

The app provides several alerts, messages and notifications to let the users know when they are about to expend more than they earn or if they are about to use up their budget for a specific category.

Skeleton
Skeleton
Skeleton
Responsibilities:
  • Created project architecture;
  • Created the marketing site;
  • Deployed the app to iOS;
  • Was part of the project's planning, research and development efforts.
Project Tech stack:
React
React Native
Firebase
Senior Front-End Developer
Nov 2022 - Dec 20221 month
Project Overview

One of Texas largest landscaping groups. Oscar was in charge of the migration of their CRM from an old version of React to a newer version in Next.js

Skeleton
Skeleton
Skeleton
Responsibilities:
  • Implemented Storybook;
  • Refactored the logic to show user visits in the system's scheduler;
  • Fixed authentication errors;
  • Migrated the whole codebase from JS to TS.
Project Tech stack:
React
Hasura
Typescript
GraphQL
Next.js
React Native Developer
Aug 2021 - Mar 20226 months
Project Overview

A medical application focused on providing exercises for clients who suffer chronic pain, accidents, or pain after surgery. The React Native app syncs with sensors provided to the client to track their movements and confirm that they are doing the exercises properly.

Skeleton
Skeleton
Skeleton
Responsibilities:
  • Updated progress' bar UI;
  • Improved performance in the pre-workout session screen;
  • Added a survey at the end of each training for the users to rate their session;
  • Upgraded to typescript's latest version;
  • Fixed bugs in several exercises where the image wasn't displaying correctly;
  • Wrote unit tests.
Project Tech stack:
React Native
Typescript
Jest
Apollo GraphQL
React Native Developer
Nov 2019 - Mar 20204 months
Project Overview

An application dedicated to improving users' lives by tracking fasting hours, providing helpful resources to improve their diet, and connecting with other users as a community.

Skeleton
Skeleton
Skeleton
Responsibilities:
  • Improved the app's performance by 30% in the initial screen and profile views
  • Wrote unit tests
  • Configured Hermes for Android builds
  • Implemented victory-native to show graphs in the user's calendars.
Project Tech stack:
React Native
Jest
Styled-components
Typescript
Apollo GraphQL
Hermes
Tech Lead
May 2019 - Nov 20195 months
Project Overview

An application helping users find the best real estate opportunities by providing several key indicators to determine the price of properties and their possible growth in value.

Skeleton
Skeleton
Skeleton
Responsibilities:
  • Created stories alongside the PM;
  • Implemented storybook to test components;
  • Worked on the Front-End architecture;
  • Integrated ApolloGraphQL;
  • Handled constant communication with the client to present updates and lead debugging sessions with the team.
Project Tech stack:
React Native
Storybook
Jest
hermes
Typescript
Apollo GraphQL
Styled-components
Front-End Developer
Dec 2018 - Mar 20192 months
Project Overview

The site shows the player's roster, games schedule, news, and blog posts about what the team is doing in the games and as an organization.

I was in charge of renovating their site using a new design system that alligned with the team's uniform and stadium seat layout for their 2020 season.

Skeleton
Skeleton
Skeleton
Responsibilities:
  • Implemented the new design in all the sections under the "Community" tab: education, athletics, activities, foundation, scholarships, donations, HEAT academy, community requests, jr.HEAT;
  • Redesigned the team roster page;
  • Improved A11Y and overall web core vitals.
Project Tech stack:
Drupal
HTML
CSS
SASS

Languages

English
Advanced

Hire Oscar or someone with similar qualifications in days
All developers are ready for interview and are are just waiting for your requestdream dev illustration
Copyright © 2025 lemon.io. All rights reserved.