Open to opportunities

João Jonhy Nmmgz

@joojonhynmmgz

Message

I am a senior full-stack software engineer specializing in React, Next.js, Node.js and scalable web systems.

Brazil

Message

What I'm looking for

I’m seeking senior full-stack roles using React/Next.js and Node.js to build scalable web applications with clear technical ownership, collaboration, and mentorship opportunities.

I am a senior full-stack software engineer with experience delivering production web applications at Yssy Co., Grupo Elfa and BairesDev, including the Price Request Portal - SEARA and a web-based Credit Analysis and Invoice approval system. I have built React/Next.js frontends and Node.js/NestJS backends, and worked with GraphQL, Dgraph, serverless architectures and relational databases.

I combine hands-on development with infrastructure and operations experience—maintaining Linux servers, Docker deployments and CI/CD pipelines—and I’ve led projects and supported customers in SaaS and agency environments. I pursue continuous learning (JavaScript, TypeScript, DDD) and bring a practical, results-oriented approach to building maintainable, high-performance systems.

Experience

Work history, roles, and key accomplishments

Current

Senior Software Engineer

Current

Yssy Co.

Dec 2023 - Present (1 year 8 months)

Developed the Price Request Portal (SEARA) as a fullstack engineer using React/Next and NestJS with TypeORM, integrating Oracle DB to support pricing workflows.

Developed a Databricks app with a Python FastAPI backend and a React frontend

ReactJS NestJS TypeORM Oracle JavaScript REST APIs Fullstack Development

Current

Senior Software Engineer

Current

Grupo Elfa

Aug 2023 - Present (2 years)

Built a web-based credit analysis and invoice approval system using React/Next with a Postgres-backed NodeJS/Express API to streamline approval workflows.

ReactJS PostgreSQL NodeJS Express REST APIs Fullstack Development JavaScript

Senior Software Engineer

BairesDev

Nov 2021 - Jun 2023 (1 year 7 months)

Developed web applications for a Newsela client using React, NodeJS and GraphQL, leveraging Dgraph and serverless patterns with CI pipelines to deliver scalable features.

ReactJS NodeJS GraphQL Dgraph Serverless CI CD GitHub Actions)JavaScript

Senior Web Developer

Tegra

Jan 2021 - Nov 2021 (10 months)

Delivered a time-boxed Score application using NodeJS and ReactJS, integrating RabbitMQ queues and Jenkins pipelines to deploy microservices.

NodeJS ReactJS RabbitMQ Jenkins Microservices CI CD JavaScript

Senior Web Developer

Apis3

Nov 2019 - Dec 2020 (1 year 1 month)

Built full-stack web solutions for agency clients and internal projects using PHP/Laravel, MySQL and Docker on Linux, handling data modeling and deployments.

PHP Laravel MySQL Docker Linux JavaScript NodeJS CSS3

Senior Web Developer

JM Web Design

Jan 2011 - Nov 2019 (8 years 10 months)

Developed websites and applications for multiple clients (including Elo 91), provided end-customer support and managed Linux server installation and maintenance.

HTML5 CSS3 JavaScript PHP MySQL Linux Git Data Modeling

Senior Web Developer

Xplendid!place

Jul 2018 - Sep 2019 (1 year 2 months)

Developed and managed a customer-satisfaction SaaS platform, handling application development, Linux server maintenance, customer support and UI creation.

HTML5 CSS3 SASS JavaScript PHP MySQL Linux Git

Education

Degrees, certifications, and relevant coursework

E-learning platforms

Professional Development, Web and Software Development

2012 -

Ongoing online coursework since 2012 covering JavaScript, TypeScript, Domain-Driven Design, ReactJS, MySQL, and PHP.

Saint Paul School of Finances

Master of Business Administration, Stock Analysis

2007 - 2008

MBA focused on stock analysis and financial modeling using relational databases and VBA.

Fundação Armando Álvares Penteado

Bachelor of Business Administration, Business Administration (IT focus)

2001 - 2005

Activities and societies: Internship at America S/A – Frutas e Alimentos developing financial reports (realized and forecasted cash flows, accounts payable and receivable) using Excel and VBA.

Business Administration degree with an IT focus; completed an internship developing Excel/VBA solutions to generate cash flow and accounts reports from ERP CSV exports.