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Igor de Castro
igor@dev:~$

Full Stack Developer // Mid-Level

Igor
de Castro_

> I modernize large-scale systems and build fast, accessible web products with measurable quality.

view_projects download_resume.pdf contact-->
4+
years in tech
10+
systems delivered
950+
automated tests

// 01 — ABOUT

The developer behind the code

cat about.txt

> Mid-Level Full Stack Developer with over four years of professional experience in technology, working continuously in software development since 2022. At Minsait, an Indra Group company from Spain, I contribute to large-scale enterprise systems for public healthcare, traffic, and defense.

$ I bring solid experience across Java 11, 21 and 25, Spring Boot, Quarkus, Angular, Vue, TypeScript, PostgreSQL, and Oracle. I currently contribute to the modernization of SINGRA 2 for the Brazilian Navy, migrating a legacy frontend architecture to Angular 21 and REST/JSON APIs with JWT Bearer authentication, and upgrading the backend to Spring Boot 4 with Java 25.

$ My work spans technical analysis, business rules, integrations, relational databases, SonarQube, automated testing, and agile delivery. In my own products, I turn the same engineering discipline toward privacy, performance, accessibility, and measurable quality.

current_status
Mid-Level Full Stack Developer · Minsait - Indra Group (Spain)
location
Goiânia, GO, Brazil · UTC−3
email
igorpcferreira@gmail.com
languages
Portuguese (Native)English (Advanced (C1))

// 02 — STACK

Technologies I use to deliver

01

Backend

  • [Java]
  • [Spring Boot]
  • [Quarkus]
  • [REST APIs]
  • [JPA/Hibernate]
  • [Maven]
  • [MapStruct]
  • [Node.js]
  • [NestJS]
02

Frontend

  • [AngularJS]
  • [Angular]
  • [React]
  • [Next.js]
  • [Vue]
  • [TypeScript]
  • [JavaScript]
  • [HTML]
  • [CSS]
  • [Tailwind CSS]
03

Data & infrastructure

  • [PostgreSQL]
  • [Oracle]
  • [Microsoft SQL Server]
  • [Redis]
  • [Docker]
  • [Flyway]
  • [Git]
  • [Bitbucket/GitLab]
  • [Jenkins]
  • [Bamboo]
04

Quality & architecture

  • [SonarQube]
  • [JUnit]
  • [Vitest]
  • [Playwright]
  • [Unit / Integration / E2E]
  • [Clean Architecture]
  • [DDD]
  • [Strategy]
  • [Agile / Scrum]

// 03 — EXPERIENCE

Enterprise scale. Product mindset.

  1. Minsait - Indra Group (Spain)

    Mid-Level Full Stack Developer

    Mar 2025 — Present · Goiânia, GO · Hybrid · Software Factory

    > Building and modernizing large-scale systems across public healthcare, traffic, and defense, moving confidently between legacy constraints and modern architectures.

    • Java
    • Spring Boot
    • Quarkus
    • Angular
    • Vue
    • PostgreSQL
    • Oracle
    View full scope
    • Development and maintenance of large-scale enterprise solutions, covering technical analysis, estimation, implementation, testing, validation, and support.
    • Implementation of APIs, business rules, validations, integrations, and data access with Java, Spring Boot, and Quarkus, plus interfaces in Angular, Vue, and TypeScript.
    • Creation, analysis, and optimization of SQL queries in PostgreSQL and Oracle, with a focus on consistency, traceability, and performance.
    • Simultaneous work across legacy and modern stacks, contributing to incremental improvements and technology migrations without compromising existing business rules.
    • Static code analysis with SonarQube on the Brazilian Navy project, supporting continuous improvement of code quality and maintainability.
    • Daily collaboration with analysts, QA, architects, DBAs, and technical managers in dailies, planning, reviews, and retrospectives.

    Selected enterprise systems

    SINGRA 2 / SINGRA21 Modernization

    Apr 2026 — Present · Brazilian Navy

    Migration of a legacy frontend architecture to Angular 21 and REST/JSON APIs with JWT Bearer authentication; backend upgrade to Java 25 and Spring Boot 4 while preserving the service, business, and persistence layers. Oracle.

    Legacy SINGRA 2

    Sep 2025 — Apr 2026 · Brazilian Navy

    Enhancement and support of enterprise modules on a legacy Java, Spring Boot, and Angular stack with Oracle, including caching and session-handling layers.

    SIDOAR

    Apr 2025 — Sep 2025 · Goiás State Department of Health

    Integrated Organ Donation and Recipient Evaluation System. Java 11, Spring Boot, AngularJS, and PostgreSQL.

    SRIE

    Dec 2025 — Feb 2026 · Goiás State Department of Health

    Immunobiological Products System for People with Special Conditions. Java 21, Spring Boot, AngularJS, and PostgreSQL.

    BATEU — Citizen / Police Officer

    May 2025 — Jun 2025 · CELEPAR

    State Traffic Accident Registry for the Paraná Military Police. Java 21, Quarkus, Vue, and PostgreSQL.

    SISESG

    Mar 2025 — Apr 2025 · Goiás State Department of Health

    Health School System. Java 11, Spring Boot, AngularJS, and PostgreSQL.

  2. DocNix

    Full Stack Developer

    Aug 2022 — Mar 2025 · Goiânia, GO · Hybrid · Internal promotion

    1. ↳ Junior Full Stack DeveloperApr 2024 — Mar 2025
    2. ↳ Full Stack Developer TraineeJun 2023 — Apr 2024
    3. ↳ Full Stack Developer InternAug 2022 — Jun 2023

    > Grew from Intern to Trainee and Junior Developer while evolving a quality-management platform used in real customer environments.

    • Java
    • Spring Boot
    • AngularJS
    • Angular 17
    • PostgreSQL
    • Docker
    View full scope
    • Promoted internally from Intern to Trainee and Junior Full Stack Developer, taking on greater autonomy and responsibility for more complex tasks.
    • Development and enhancement of DocNix, an integrated quality management, organizational excellence, and business process platform, using Java, Spring Boot, AngularJS, and Angular 17.
    • Implementation and maintenance of APIs, business rules, data processing, inter-module communication, reusable components, directives, and UX improvements.
    • Creation and optimization of SQL queries in PostgreSQL, Oracle, and MySQL, as well as analysis and resolution of real customer incidents in staging and production.
    • Contributed to software architecture, Docker environments, Git version control, and agile ceremonies, collaborating with cross-functional teams on product delivery and support.

  3. Fundação Jaime Câmara

    Technical Support

    Apr 2022 — Jul 2022 · Goiânia, GO · On-site

    > Built the operational foundation of my career by diagnosing incidents and keeping internal users productive.

    • Hardware
    • Software
    • Support
    View full scope
    • On-site technical support, system installation and configuration, preventive maintenance, and hardware and software diagnostics.
    • Remote support and incident resolution, reducing downtime for internal users.

// 04 — PROJECTS

Products with evidence, not promises

Preview of Aura

Aura

Concept jewelry experience with a 3D configurator

Kyber concept project

An original study for a fictional jewelry brand, with editorial art direction and an interactive ring to explore gemstones, metals, and the structure of the piece.

Photography and opening film created with AI. Includes alternatives for reduced motion and unavailable WebGL.

  • #React
  • #Three.js
  • #WebGL
  • #Vite
Preview of BRUMA

BRUMA

Interactive experience for a fictional gin brand

Kyber concept project

A concept study featuring a real-time 3D bottle and floating botanicals, exploring visual direction and interaction to present a fictional product.

  • #3D
  • #WebGL
Preview of Casa Umbra

Casa Umbra

Concept architecture in a scroll-driven tour

Desktop website. On mobile, watch the video.

Kyber concept project

A fictional desert residence presented in eight scenes, with transitions and an amber light guiding the tour. Images created with AI.

  • #HTML
  • #CSS
  • #JavaScript
Preview of André Mei

André Mei

Surfing, ultramarathons, and partnerships in a personal website

An athlete website bringing together his story, surf gallery, destinations, and partnership contact. The opening features interactive WebGL water and automatically updated channel videos.

  • #WebGL
  • #Responsive design
Preview of Igor de Castro · Model

Igor de Castro · Model

Editorial, streetwear, and portrait portfolio

Personal project

A modeling portfolio with selected photography, gallery navigation, and a personal presentation in a responsive editorial interface.

  • #HTML
  • #CSS
  • #JavaScript
Preview of Kyber Tech

Kyber Tech

Technology studio — websites, automation, and AI

Co-founder · 2026 — Present

Technology studio focused on websites, automation, artificial intelligence, and digital products.

Direct involvement from needs discovery and solution definition through development, deployment, and consultative client relationship management.

  • #Web development
  • #Automation
  • #Applied AI
  • #Product
Preview of Manu's Barbearia

Manu's Barbearia

Barbershop site with subscription plans and booking

Kyber Tech client

Single-page site for a barbershop in Goiânia: nine services, four subscription plans compared side by side, salon gallery, and booking that goes straight to Booksy.

Astro islands architecture: React only where interaction is needed, such as the open/closed badge, the gallery lightbox, and the animated counters. The rest ships as static HTML.

  • #Astro 7
  • #React 19
  • #TypeScript
  • #Tailwind CSS 4
  • #shadcn/ui
  • #Vercel
Preview of KOUNTING Streetwear

KOUNTING Streetwear

Streetwear catalog with orders closed on WhatsApp

My own brand

Storefront for KOUNTING, my own streetwear label of oversized tees in limited drops. Catalog with category filter, photos per color, sizing guide, and a button that reaches WhatsApp already carrying the piece, color, and size.

Statically exported Next.js, no transactional checkout by design. Hand-written CSS, no UI framework, and self-hosted fonts.

  • #Next.js 14
  • #React 18
  • #Static export
  • #anime.js
  • #Vercel
Preview of Gabriela Camargo

Gabriela Camargo

Photographer portfolio with lightbox gallery

Zero dependencies

Site for a photographer working in Goiânia since 2016: a gallery that enlarges photo by photo, the two session formats and what each one includes, weddings by quote, and WhatsApp in every section.

Pure static HTML and CSS, no build step and no dependencies. The only JavaScript is the gallery lightbox, written by hand. Self-hosted fonts and images served as WebP.

  • #HTML
  • #CSS
  • #Vanilla JavaScript
  • #WebP
  • #Vercel
Preview of Compressify

Compressify

Private in-browser image compression and conversion

−86% in a measured batch

Static, offline application for batch compression and conversion of JPG, PNG, WebP, and AVIF images. All processing runs client-side using Web Workers and WebAssembly; files never leave the browser.

389 unit and integration tests, 115 E2E tests across Chromium, Firefox, and WebKit. Lighthouse: 95 performance and 100 accessibility, best practices, and SEO.

  • #Next.js 16
  • #React 19
  • #TypeScript 6
  • #WebAssembly
  • #Vitest
  • #Playwright
Preview of QR Code Studio

QR Code Studio

Static vector QR generator with automatic verification

Lighthouse 100 · a11y / best practices / SEO

Client-side product supporting nine content types, including Pix BR Code, SVG/PDF/PNG export, print-ready frames, customization, local history, and batch generation from CSV files.

Every QR code is rasterized and decoded before export. Includes 369 unit and integration tests and 86 E2E tests.

  • #Next.js 16
  • #React 19
  • #TypeScript strict
  • #pdf-lib
  • #jsQR
  • #Vitest
  • #Playwright

FitJourneyAI

AI-powered fitness tracking assistant on Telegram

Bachelor's thesis

Chatbot featuring onboarding, weight and body measurement tracking, workout completion logging, progress charts, summaries, and AI-generated workouts, including audio processing with Whisper.

Architecture based on Clean Architecture and the Strategy Pattern.

  • #Java
  • #Spring Boot
  • #PostgreSQL
  • #Redis
  • #n8n
  • #OpenAI / Whisper
  • #Docker
  • #Telegram API

FROM IDEA TO PROJECT

Your project starts with a conversation.

Tell me what your business needs. We’ll decide what makes sense to build and agree on the next steps.

  1. 01We understand your needs.
  2. 02You receive a scope, timeline, and price.
  3. 03Once you approve the proposal, we start.
What do you need?
Let’s discuss my project

Opens WhatsApp with a message you can complete.

// 05 — FOR YOUR BUSINESS

Need a website or automation?

> Beyond my day job, I run a technology studio with another developer. If your business needs a site, an automation, or applied AI, this is where that work happens.

01

Website and catalog

An address of your own, built for the phone, where people find you and reach you without going through Instagram DMs.

  • ▸Institutional site
  • ▸Product catalog
  • ▸Portfolio and gallery
  • ▸Own domain

02

Automation and integrations

Repetitive work that today runs by hand: messages, scheduling, spreadsheets, and systems that do not talk to each other.

  • ▸WhatsApp flows
  • ▸Booking and forms
  • ▸API integrations
  • ▸Internal panels

03

Applied AI

AI put to work on a real problem in your operation, not as a demo. Chat assistants, classification, and content support.

  • ▸Service assistants
  • ▸Content generation
  • ▸Data processing
  • ▸Custom chatbots

studio

Kyber Tech_

Websites and automation for small businesses, on a monthly subscription. Two developers, direct contact, no agency in between.

open_kyber_tech see_pricing

Talking to Kyber reaches me or my partner. Either way you talk to the developer who builds it.

// 06 — EDUCATION

Foundations and continuous learning

~/education/main

Bachelor of Science in Computer Science

PUC Goiás · Pontifical Catholic University of Goiás

2021 — 2026

  • Bachelor's Thesis: FitJourneyAI, an AI-powered fitness tracking assistant on Telegram.
  • Academic tutor during the 2021/2 semester, supporting students in programming and computational logic.
  • Participated in problem-solving activities, including the Brazilian Informatics Olympiad and the SBC Programming Marathon.

Selected courses and certifications

// 07 — CONTACT

Let’s build something that matters.

Modernizing a critical system, shaping a new product, or solving a technical challenge that needs an end-to-end view? Message me on WhatsApp and tell me what you are building. You will talk directly to me.

start_on_whatsapp send_emailLinkedInGitHub

Looking for a website or an automation for your business? talk_to_kyber_tech

Prefer the full version? download_resume.pdf