Hi, I'm João Marcus Fernandes

Staff Software Engineer | Back-end Specialist

Tech Lead | Cloud Computing | Go / Golang | Node.js | MongoDB

I’m a passionate software engineer since 2014, I have experience building scalable and efficient systems. I’ve had the opportunity to work with companies across the globe, including Brazil, North America, Europe, and Asia, gaining a deep understanding of diverse tech ecosystems.

I specialize in Back-end development, with a strong focus on Go (Golang) and Node.js, and have extensive experience designing and optimizing cloud-native architectures using AWS and GCP. My expertise also includes working with MongoDB for database solutions and leveraging modern technologies like JavaScript/TypeScript (React.js, Next.js, Vue.js), Python, and Ruby (Ruby on Rails, Sinatra) to deliver robust, high-performance applications.

Whether it’s leading technical teams, architecting scalable systems, or mentoring developers, I’m driven by the challenge of solving complex problems and delivering impactful solutions.

Want to know more? Check out my About Me page!

Work Experience

June 2014

Present

Highlighted Skills

GinMuxgRPCConcurrent GoChannelsRestAPIsCLI ToolsWeb CrawlingGateway API

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JavaScript

NodeJSReactReact NativeVueJSExpressJestMochaUniversal ComponentsServerlessCLI ToolsWeb CrawlingGateway API

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MongoDB

MongooseAtlasCompassAggregationIndexingReplication

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Agile

ScrumXPKanbanJiraTrello

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Architecture

Cloud ComputingMicroservicesMVCMVVMSOAClean ArchitectureHexagonal ArchitectureEvent-Driven ArchitectureServerlessDistributed Systems

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Cloud Providers

AWSLambdaS3EC2RDSGCPFirebaseCloud FunctionsAzure

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Communication

Active ListeningConflict ResolutionNon-Violent CommunicationPublic SpeakingStorytellingAsync CommunicationClient-Driven Communication

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Git

Git FlowMulti-repositoryVersioning PackagesGit HooksFast-Forward FlowsGit Bisect

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Leadership

Team BuildingDecision MakingSmart Delegation

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Highlighted Posts

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Dicas de um Entrevistador Técnico

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How to Use My Dotfiles

Como usar meu Dotfiles

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Data Structure 101: Part 04

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Aprendendo a utilizar HTTP

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Dicas para conseguir o seu primeiro emprego em TI

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Thinking Functional: now with example and cats

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Ideias para você começar um Portfólio Dev

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Criando seu primeiro site com GitHub Pages

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Data Structure 101: Part 03

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Data Structure 101: Part 02

O Triângulo invertido do Front-end - TDC

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Teaser - Front-end in TDC - The Developer’s Conference

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Data Structure 101: Part 01

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Front-end in 2020 - Presentation

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Refletindo sobre mulheres na computação e comunidades tóxicas

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Testando JavaScript corretamente com Mocha + ES6 + Gulp

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How moving from Design to Back-end made me a better Front-end

Highlighted Projects

joaomarcuslf/leet-discuss
Archive LeetCode Challenges

joaomarcuslf/gardevoir-ex-damage-calculator
Automatic Damage Calculator

joaomarcuslf/gas_sensor_iot
Gas Sensor IoT

joaomarcuslf/pico_reaction_game
Pico Reaction Game

joaomarcuslf/code-challenges
Code Challenges

joaomarcuslf/sucellus
Docker Cloud Provider

joaomarcuslf/color-generator
Color Generator API

joaomarcuslf/qr-generator
QR Generator API

joaomarcuslf/keyforge-name-of-the-day
This is my take on Twitter bot with Go.

joaomarcuslf/ticket-creator
This is a service that creates Tickets to be shared for others.

joaomarcuslf/workspace-configs
My default settings for most of my projects

arctouch/web-tests-factory
Tests Factory for most of the Web Frameworks

joaomarcuslf/go-go-url-go
This is and URL shortener repo written in Go, using Redis and Docker.

joaomarcuslf/grpc-golang-example
POC using gRPC to learn

joaomarcuslf/docker-golang-api-template
POC using gRPC to learn

joaomarcuslf/auth-blog-service
RestAPI, using JWT and Auth by Role

joaomarcuslf/mentorship
This project contains the codes used for the mentorship I'm giving

joaomarcuslf/textual-emotion-detect
POC of how to detect text emotions.

joaomarcuslf/python-advanced-studies
An repository for my studies in Python.

joaomarcuslf/react-graphql-country-list
An application built with React, and Redux. Consuming GraphQL Api.

joaomarcuslf/react-flask-application
An application built with React, Flask, Postgres and Docker.

joaomarcuslf/web-gongyo
A place to pray.

joaomarcuslf/mtg-csv-generator
This repo will show some of my data-science studies using MTG cardbase

joaomarcuslf/data-science-studies
Repo to show how my studies about data science are going

joaomarcuslf/sabaki-i18n
My contributions to Sabaki i18n

joaomarcuslf/react-express-ssr
SSR example using React and ExpressJS

joaomarcuslf/golang-studies
Repo to show how my studies about Golang are going

joaomarcuslf/react-goban
Migrated Goban component to modern React

joaomarcuslf/pbl-tcc-bucket
This is the AWS Bucket API for the PBL project

joaomarcuslf/pbl-tcc-front
This is the Front-end built in VueJS for the PBL project

joaomarcuslf/pbl-tcc-api
This is the Rest Api Back-end built in Ruby on Rails and PostgreSQL for the PBL project

joaomarcuslf/cross-event
Module for Event communication for React Native, Node and Browser

joaomarcuslf/rasp-monitor-bot
Clojure Bot for Raspberry Pi

joaomarcuslf/authorization-api
JWT Api Authorization built in several languages

joaomarcuslf/clojure-catalog-service
Example of a catalog api built in Clojure

joaomarcuslf/clojure-rest-api
Clojure REST API