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Catalin – Swift, Node.js, React Native, experts in Lemon.io

Catalin

From Romania (GMT+3)

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Full-stack Web DeveloperStrong senior
Hire developer
14 years of commercial experience
Administration
AI
Beauty
Dating
E-commerce
Entertainment
Fintech
Gamedev
Hospitality
Media
Music and audio
Productivity
Social media
Marketplace
Subscription
Broadcasting software
Mobile apps
Video streaming software
Lemon.io stats
3
projects done
1120
hours worked
Open
to new offers

Catalin – Swift, Node.js, React Native

Catalin is a senior full-stack engineer with more than 10 years of experience in the tech world. He has great expertise in cross-platform development using React/React Native, Swift, Node.js, and proficiency in both databases and cloud networks. Having worked in start-ups from all around the world, Catalin knows how to bring value during sprints and impress his colleagues with great soft skills.

Main technologies
Swift
4 years
Node.js
4 years
React Native
6 years
React
4 years
JavaScript
12 years
Next.js
4 years
Additional skills
Heroku
Typescript
MongoDB
PostgreSQL
Firebase
Webflow
Java
Swagger
GraphQL
SQL
iOS
AWS Lambda
Expo
AI
MySQL
Objective C
ElasticSearch
Python
Redux Saga
Solidity
Smart contracts
Vue.js
Express.js
Prompt engineering
LLM
Blockchain
GPT
OpenCV
Cloudflare
AWS
MapBox
Turborepo
Vite
Ready to start
ASAP
Direct hire
Potentially possible

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Experience Highlights

Developer
Sep 2023 - Ongoing1 year 4 months
Project Overview

This is a Google Workspace plugin that uses AI (ChatGPT or Claude) to convert the user prompt into actions that it performs inside the spreadsheet. This was a showcase project for Catalin's AI skills.

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Responsibilities:
  • Created the Google scripts frontend and functionality;
  • Prompt engendered the LLM request to provide the best response;
  • Developed and deployed the backend.
Project Tech stack:
Google scripts
Google API and Services
AI
LLM
Prompt engineering
Claude LLM
Node.js
Express.js
Postman
PostgreSQL
Heroku
Machine learning
OpenAI API
Tech Lead
Dec 2022 - Mar 20241 year 3 months
Project Overview

This is one of the biggest players in the blockchain and metaverse ecosystem. Catalin was the technical lead for the inventory and marketplace part of the platform.

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Responsibilities:
  • Provided technical solutions for the asset upload, workspace, inventory, and market sections of the platform;
  • Conducted audit of the NFT minting (and lazy imaging ) and transferred smart contracts;
  • Improved the search response speed using elastic search;
  • Refactored and cleaned up a large part of the code, both front end and back end;
  • Estimated tasks and milestones, delegated tasks, set deadlines and clear goals, coordinated with team members, and synced with teams all around the globe (Argentina, Uruguay, France, Romania, China);
  • Proposed architecture solutions for various tasks and improvements.
Project Tech stack:
Vue.js
Typescript
JavaScript
Node.js
MySQL
Express.js
ElasticSearch
Solidity
Smart contracts
web3.js
Cloudflare
Crypto
Blockchain
CTO / Only Developer
Jun 2021 - Jan 20231 year 7 months
Project Overview

Honest dating and personal growth cross-platform mobile app. Uses AI to check for indecent photos and has a proprietary matching algorithm. Also includes a personal growth section.

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Responsibilities:
  • Architected and built the entire platform by himself;
  • Built the backend with a focus on optimizing for cloud services costs while not sacrificing user experience;
  • The app was hosting 10k users (500 daily average and 100 peek active at once). Cloud services cost under $100.
Project Tech stack:
React Native
Firebase
Typescript
Adobe Photoshop
React Native
Typescript
AI
Firebase
Firebase Analytic
Firebase DB and Storage
Firebase Cloud Messaging
Firebase Crashlytics
Trainer
Jul 2022 - Dec 20225 months
Project Overview

This is one of the largest course providers dedicated to people who want to do a reconversion in their career. It has offers in a lot of directions from business analytics to design and software development.

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Responsibilities:
  • Taught a class of 16 students of all ages (from 20 to 45) front-end development. 6 got hired in the industry after this course.
Project Tech stack:
React
HTML
CSS
JavaScript
Team Lead / Software Developer
Feb 2022 - May 20223 months
Project Overview

Excel + Powerpoint + extra functions all in the cloud. Started as a prototype but, because development was moving so fast, the client pivoted towards a full product. Build the MVP and the rest of the requested features moving towards a real serious product. Was the Team Lead when new developers arrived. The Senior Architect who took over the project was impressed with the speed of the system and the technologies stack used.

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Responsibilities:
  • Implemented 80% of Excel and 90% of PowerPoint functionality in a project hosted in the cloud;
  • Implemented Google login;
  • Created a scalable architecture focused on fast development (clients' former devs were also impressed by the performance of the system).
Project Tech stack:
React
Node.js
HTML
CSS
Strapi
MongoDB
Google API and Services
Cross-platform Mobile Developer
Sep 2021 - Jan 20224 months
Project Overview

The platform offers barber services for customers at their desired locations.

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Responsibilities:
  • Built the mobile client used for booking barber appointments;
  • Solo-developed a mobile app from scratch;
  • Used existing GraphQL API.
Project Tech stack:
React Native
Typescript
Stripe API
GraphQL
React Native
GraphQL
VP of Information Technology
Feb 2021 - Sep 20217 months
Project Overview

A multi-vendor marketplace, like Amazon, centered on nature-inspired goods with a big focus on the user experience.

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Responsibilities:

It was a client without a tech background, so Catalin was responsible for the entire development branch.

  • Created a modular "microservices" inspired architecture (the client wanted to have the possibility to expand the platform towards video streaming, chat/dating app);
  • Implemented the mobile client (the only developer) Team lead / main developer for the backend;
  • Supervised and reviewed code for two junior developers;
  • Supervised the frontend development and reviewed code written by the juniors;
  • Was in charge of DevOps, deployments, and pipelines;
  • Trained two junior developers to help/continue the project and was responsible for extracting tasks and subtasks, prioritizing, and creating estimations.
Project Tech stack:
React Native
Node.js
Django
PostgreSQL
Redis
Heroku
Stripe API
Next.js
GraphQL
Typescript
Redux
Strapi
Redux Saga
React
Postman
Tech lead / Frontend
Nov 2019 - Apr 20204 months
Project Overview

Live virtual campus tours that connect student guides with visitors from any part of the world.

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Responsibilities:
  • Created the architecture for the front-end part of the system;
  • Coordinated part of the front-end team;
  • Implemented part of the dashboard;
  • Used low-code to build the landing page
Project Tech stack:
React
AWS
MapBox
Full-stack Developer
Apr 2018 - Jul 20191 year 3 months
Project Overview

iOS app that gathers restaurant reviews. The reviews were based on the user context and their older preferences. Used IBM Watson AI to generate recommendations.

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Responsibilities:
  • Was fully responsible for developing the mobile iOS and back-end parts of the application;
  • Integrated React Native modules in a native iOS app;
  • Implemented a Facebook crawler that would get the restaurants from a specific area.
Project Tech stack:
Swift
Amazon Lambda
DynamoDB
Swift
iOS
React Native
Typescript
iOS Developer / Back-end Developer
Mar 2014 - Feb 20183 years 11 months
Project Overview

A call-to-listen solution for small radios that don't have the power to broadcast across states. The user would call a phone line and listen to the radio broadcast.

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Responsibilities:
  • Implemented the iOS mobile application;
  • Embedded React Native in an iOS App to provide chat functionality;
  • Integrated a money transfer solution inside the app;
  • Implemented an OGG audio encoder/decoder.
Project Tech stack:
Objective C
Swift
Java
Swagger
MySQL
React Native
JavaScript
Xcode
Visual Studio Code

Education

2009
Computer Science
Bachelor's

Languages

English
Advanced

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