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Guillem – Golang, React, Next.js, experts in Lemon.io

Guillem

From Argentina (UTC-3)flag

Full-stack Web Developer|Senior
Lemon.io stats
1
projects done
2880
hours worked
1
offers now 🔥

Guillem – Golang, React, Next.js

Guillem is a passionate and open-minded software developer with a strong desire to contribute to resilient solutions and new projects. He brings solid expertise in Go, SQL, and NoSQL databases, along with practical experience in AWS. In addition, Guillem possesses a deep understanding of programming concepts and demonstrates proficiency in JavaScript, TypeScript, React.js, Next.js, and Node.js. Guillem's strengths include his theoretical understanding, good presentation skills, and a keen interest in new approaches to web development. Overall, Guillem is a technically adept and versatile developer with a strong foundation in software development.

7 years of commercial experience in
E-commerce
E-learning
Edtech
Healthtech
Retail
B2B
Enterprise software
Platforms
Software development
Main technologies
Golang
4 years
React
6 years
Next.js
1 year
Typescript
6 years
Node.js
6 years
Additional skills
AWS
PostgreSQL
MongoDB
Cloudflare
Vercel
Amazon EC2
DocumentDB
Express.js
Amazon RDS
OpenAI API
Golang REST API
NoSQL
Amazon SQS
GCP
MySQL
CI/CD
Microsoft Azure
Redis
PHP
CakePHP
Direct hire
Possible
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Experience Highlights

Senior Back-end Developer
Oct 2023 - Nov 20252 years
Project Overview

This is a data streaming tool for software and data engineers. Its purpose is to help you move data from A to B. You can use the tool to send data from Kafka to Postgres, between files and APIs, between supported connectors, and any data store you can build a plugin for.

Guillem maintained many connectors and processors for the project.

Responsibilities:
  • Built conduit-connector-mysql; it included database locking, opencdc position restoring, and many more features. For reference, this connector competes with mysql debezium;
  • Developed and updated 10+ connectors;
  • Learned how to use many different queue systems like pulsar, rabbitmq, kinesis;
  • Learned how to work in an open-source environment.
Project Tech stack:
Golang
CI
CD
GitHub Actions
RabbitMQ
MySQL
Amazon SQS
ActiveMQ
Integration Testing
OpenAI API
Senior Full-stack Contractor
Jul 2021 - Dec 20243 years 5 months
Project Overview

An online platform designed to assist students in preparing for university entry exams. It offers a suite of study resources, tutorials, and practice materials to help learners enhance their understanding and ace their tests. The platform provides a tailored learning experience with accessible and structured content that's geared toward achieving academic goals.

Responsibilities:
  • Removed tedious manual jobs using OpenAI chat models;
  • Mitigated account sharing using session tracking and device management;
  • Integrated with Vimeo video.
  • Helped design a custom streaming solution with AWS S3 and cloudfront.
Project Tech stack:
AWS
PostgreSQL
Golang
OpenAI API
CakePHP
PHP
Senior Full-stack Developer
Aug 2019 - Jan 20233 years 5 months
Project Overview

The ideal solution to track current analytics in the MercadoLibre marketplace. Sellers could easily track what was trending in each category and could measure their own sales performance.

Responsibilities:

• Migrated PHP monolith to Node.js and Go microservices. • Improved data performance pipeline by 300% with Go. • Built multiple TypeScript React SPAs. • Managed PostgreSQL on AWS RDS; built MongoDB aggregation pipelines. • Built web scraping services with Puppeteer and Apify.

Project Tech stack:
PHP
Node.js
Golang
Typescript
Web scraping
MongoDB
Senior Full-stack Developer
Feb 2020 - Dec 20222 years 10 months
Project Overview

B2B ecommerce analytics tool that helps companies such as MercadoLibre and Black & Decker manage and track tens of thousands of product prices. With Spiral Pricing, sellers can study price changes in real time, enabling them to have great market insights in a short amount of time.

Responsibilities:
  • Helped grow the product from a few users to tens of sellers;
  • Built a full-stack app with better perceived UX than the previous legacy monolith;
  • Trippled the speed of multiple background jobs;
  • Integrated with axiom.co to facilitate comprehensive application monitoring and performance analysis;
  • Wrote unit and integration tests.
Project Tech stack:
React
Node.js
PostgreSQL
Golang
DocumentDB
Amazon EC2
Junior Full-stack Developer
Jan 2019 - Jul 20195 months
Project Overview

A sophisticated system that provides audio-visual functions in an operation room via a touchscreen. It facilitates live OR broadcasting and telediagnosis with high-quality, zero-latency audio and video. The system is user-friendly, adaptable across medical devices, and can be scaled or customized to meet various needs.

Responsibilities:
  • Helped maintain a big SPA;
  • Debugged hidden React memory leaks;
  • Help decouple a small part of the app into an independent sellable product;
  • Built and debugged javascript drivers with audio hardware.
Project Tech stack:
React
API
Express.js
e2e testing
Jasmine

Education

2018
Web development
Apprenticeship

Languages

German
Pre-intermediate
Spanish
Advanced
English
Advanced

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