SERGIO TOMAS
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Sergio Tomas
Sergio TomasSão Paulo, BR · 14+ years in software

// Principal Software Engineer · Solutions Architect

I architect scalable systems and lead them from first sketch to production.

Software architect and tech lead with a front-end core (React, Next.js), back-end in Node.js and Java, and cloud on AWS, Azure and GCP — now bringing AI Engineering into how products get built.

See my experienceDownload CV
years
14+
companies
8
clouds
3
Fig. 01 — How I think about a product
01 · ExperienceFront-end architectureReact · Next.js · Vue · micro-frontends · design systems
02 · ServicesAPIs & back-endNode.js · NestJS · GraphQL · Java Spring
03 · AIAI EngineeringLLMs · RAG · MCP
04 · DataData layerSQL · MongoDB · DynamoDB · Firestore
05 · PlatformCloud & deliveryAWS · Azure · GCP · CI/CD
years
14+
companies
8
clouds
3
01About

Principal Software Engineer and architect, the technical reference for architecture and system design at companies like C&A and Claro — defining standards, designing highly available systems and driving products end to end.

AI Engineering, done with engineering

I integrate generative AI, LLMs and AI agents into the development lifecycle and into the solutions I architect — using AI to accelerate delivery without compromising quality, predictability or maintainability.

Always grounded in

  • Well-defined architecture
  • Code review
  • Automated testing
  • Observability
  • Security
02Experience
2010 — today
  1. Jan 2024 — PresentBelo Horizonte, MG

    Stellar Gaming

    • Principal Software Engineer

    Software architecture and technical reference for developers. System design of the main projects, end-to-end products, and generative AI solutions with LLMs, RAG and MCP — driving AI Engineering with Claude Code and Spec-Driven Development.

    • System design
    • AI Engineering
    • Tech leadership
  2. Jan 2023 — Jan 2024São Paulo, SP

    DOMVS iT

    • Software Engineer

    Built a client's main website with Next.js as the core stack and took an active role in front-end architecture and standards decisions.

    • Next.js
    • Front-end architecture
  3. Feb 2022 — Jan 2023São Paulo, SP

    C&A Brazil

    • Senior Solutions Architect

    Corporate architecture standards, solution design and technical leadership for strategic #CeaFashionTech solutions. Led assessments and audits and drove adoption of new technologies.

    • Enterprise architecture
    • Solution design
  4. May 2017 — Feb 2022São Paulo, SP

    Claro Brazil

    • Systems Architect2021 — 2022
    • Front-end Specialist Developer2019 — 2021
    • Senior Front-end Developer2018 — 2019
    • Front-end Developer2017 — 2018

    Grew from developer to architect. Led the front-end chapter, built a micro-frontend architecture where React, Angular and Vue coexist, designed the front-end CI/CD with Jenkins and contributed to the Mondrian design system.

    • Micro-frontends
    • AWS
    • CI/CD
    • Design systems
  5. 2010 — 2017

    Where it started

    • Resource IT Solutions
      Programmer Analyst

      Angular, Java, AngularJS → Angular 2 migration, Cordova

      2016–2017
    • Tugarê | CDM São Paulo
      Programmer

      iPad web apps for healthcare on Veeva & Agnitio, PHP, WordPress

      2014–2016
    • Marvin Tecnologia
      Web Developer

      Interactive pharma presentations, .NET legacy systems

      2012–2014
    • Atento Brazil
      Web Designer

      Intranet pages, layouts and graphics

      2010–2012
03Stack

The languages and tools I build with.

Languages · 8

Tools & platforms · 29

Hover to pause · Official logos · Click for details

↳In detail

A full-cycle toolkit, from the pixel to the platform.

Front-end
React (Redux, Redux-Saga, Context API) · Next.js · Vue.js · Angular · HTML5 (semantics, accessibility, SEO) · CSS3 (Flexbox, Grid, responsive) · Micro-frontends · Design systems
Back-end & APIs
Node.js (Express, NestJS, GraphQL) · Java (Spring) · RESTful APIs · VTEX IO
Databases
MySQL · SQL Server · Oracle · MongoDB · Firestore · DynamoDB
Cloud & DevOps
AWS · Azure · Google Cloud · CI/CD (Jenkins)
Architecture
Software design · Software & platform architecture · System design · ArchiMate
AI Engineering
Claude Code · Spec-Driven Development (SDD) · MCP · RAG · LLMs & AI agents

Education

Bachelor's Degree in Information Systems

2011 — 2015

Certifications

  • AZ-400: Designing and Implementing Microsoft DevOps Solutions
  • ArchiMate 3 Foundation
  • Node.js – The Complete Guide
  • Go (Golang): Exploring Google's Language

Languages

  • Portuguese

    Native

  • English

    Full professional

  • Spanish

    Elementary

04Contact

Have a system to design or a team to lead? Let's talk.

[email protected]