LionDev Portfolio
This portfolio — Performance 100, Accessibility 100, Best Practices 100, SEO 100. Built with Nuxt 4, Tailwind, and nuxt-security. A+ Headers and strict CSP.
Nuxt 4Tailwind CSSTypeScriptnuxt-security
~/liondev $ whoami
Euclides
Santana
Full-stack developer focused on Nuxt and Vue. I build fast, accessible and secure applications — treating performance and security as part of the delivery, not as a last-minute fix.
SegurançaA+
Performance100
Boas Práticas100
Acessibilidade100
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// About Me
Who Am I
Full-stack developer based in João Pessoa, Brazil. I work with Nuxt, Vue and TypeScript, and I care about shipping projects that are fast, tidy and easy to maintain.
const developer = {
name: 'Euclides Santana',
role: 'Full-Stack Developer (Nuxt / Vue)',
focus: [
'Web Performance',
'Applied Security',
'Nuxt Architecture'
],
mission: 'Code that is fast, clear and well cared for'
}
Performance is not optional: it is the foundation of the user's experience. The projects I publish ship with Lighthouse 100, configured security headers (HSTS, CSP, X-Frame-Options), optimized images and code organised to last. This portfolio and the sites I keep online are the proof — you can check them with any public scanner.
A+Security
100Performance
100Best Practices
100Accessibility
Security Posture
✓Strict-Transport-Security (HSTS)
✓Content-Security-Policy (CSP)
✓X-Frame-Options: DENY
✓X-Content-Type-Options: nosniff
✓Referrer-Policy: strict-origin
✓Permissions-Policy: restricted
// Skills
What I work with
An organised view of what I use day to day, grouped by the role each technology plays in a project.
Interface
The core of my work — where I spend most of my time.
- Nuxt
- Vue 3
- TypeScript
- Tailwind CSS
- HTML / CSS
Back-end and data
Enough to take a whole application from the database to the screen.
- Node.js
- Nitro
- PostgreSQL
- Supabase
- REST APIs
Security and quality
Practices I apply to everything I publish, verifiable on the sites themselves.
- Security headers
- CSP
- OWASP Top 10
- Lighthouse
- Acessibilidade
Tooling and infrastructure
How I ship applications and keep them running.
- Git
- Docker
- Linux
- Caddy
- n8n
- Netlify
- Vercel
Exploring
Active study, with personal projects — not yet where I have the most mileage.
- Go
- Rust
- Python
This list is a selection of what I use regularly; other technologies come in as the project requires.
// Projects
Engineering in Action
Scalable, audited, and real-world-ready solutions.
Tempus Code Guard
Corporate website for Tempus Code Guard. Lighthouse 100 across all four categories, A+ security headers and an A+ carbon rating on Website Carbon.
Nuxt 4Tailwind CSSi18nNetlify
Automation with n8n
n8n automations for data processing, API integration and routine orchestration — running on my own infrastructure, behind a reverse proxy with HTTPS.
n8nNode.jsAPIsDocker
Civil Construtora
Corporate portal for a construction company, presenting developments and providing a contact channel. Live in production, with HSTS, a strict CSP and around 1 second load time.
Nuxt 4Tailwind CSSnuxt-security@nuxt/image
Central IA
Enterprise AI platform by MM Soluções that turns internal documents and data into a conversational search experience with source citation. I work on the interface and on the integration with the models.
Nuxt 4TypeScriptLLMRAG
// Security
Why security matters to me
A field I study and where I want to take my career.
Security is no longer the concern of a single isolated specialist. As AI advances — particularly open-weight models that anyone can run and adapt — creating and orchestrating attacks has become cheaper, faster and far more accessible. Anyone writing software today has to account for that from the very first line.
That is why I study the subject continuously and apply what I learn to what I build: security headers, strict CSP, input handling, care with secrets and exposed surface. I do not present myself as a security specialist — I present myself as a developer who takes security seriously and wants to go deeper in that direction.
- Security headers and CSP on the applications I publish
- OWASP Top 10 as a review reference
- Care with secrets, authentication and exposed surface
- Ongoing study of security applied to AI
// Availability
How we can work together
I'm available for new opportunities — in Brazil and abroad.
Remote, any time zone
Based in João Pessoa, Brazil (GMT-3). I work Brazilian hours or adapt to the client's schedule, including North America and Europe.
Full-time, contract or freelance
Fully available for full-time, part-time or one-off projects. I can invoice as a registered company (Brazilian CNPJ) when needed.
Fluent English
Eleven years teaching English at language schools and private colleges (Yázigi, Colégio Adventista, Colégio Anísio Teixeira). I work in English day to day: meetings, documentation and code review.
Start date
Available to start at short notice, with the exact date agreed around my current commitment.
// Contact
Let's talk
Open to remote opportunities and freelance projects. If you are looking for someone to build or improve a web application, get in touch.