Backend & APIs
PHP · Laravel · CodeIgniter · Symfony · Node.js · REST APIs · Integrations

Data
PostgreSQL · MySQL · MariaDB · SQL Server · Oracle · SQLite · MongoDB

Cloud & Engineering
AWS · Docker · Git · Linux · Windows · macOS · CI/CD

Applied AI
LLM integrations · Prompt Engineering · Embeddings · Semantic Retrieval · MCP · Recommendation Systems · AI Security

Senior Full Stack Developer and Applied AI Engineer focused on backend engineering, software architecture, APIs, integrations, cloud and AI-enabled systems.

My work covers the full software delivery cycle: requirements discovery, process and data modeling, architecture, development, testing, deployment, maintenance, support and continuous technical evolution.

Since 2025, I have also worked professionally with Applied AI, including LLM-based capabilities, prompt engineering, embeddings, semantic retrieval, MCP, recommendation systems, AI Security and Security by Design.

• Building and delivering software professionally since 2014 through Felix Studio.
• End-to-end ownership across requirements, process and data modeling, architecture, development, testing, deployment, maintenance and support.
• Professional Applied AI Engineering since 2025, including LLM integrations, prompt engineering, embeddings, semantic retrieval, MCP, recommendation systems, AI Security and Security by Design.
• Experience across product, corporate and contractor environments, including Safehouse App, 123Milhas, Why Digital, AcessoWeb Design and SOEBRAS.
• Backend and integration work spanning REST APIs, SQL/NoSQL databases, AWS services, authentication, payments and data-integrity controls.

My work is not limited to implementation. I operate across the engineering lifecycle and make technical decisions around:

• translating business requirements into system boundaries and delivery plans;
• API and integration architecture;
• relational and NoSQL data modeling;
• transaction boundaries, data integrity and concurrency;
• cloud and third-party service integration;
• security, privacy and authentication controls;
• testing strategy, CI and deployment readiness;
• maintainability, operational support and technical evolution.

I prefer architectures that are explicit about trade-offs, failure modes and operational responsibilities rather than adding complexity without a demonstrated need.

Current Laravel 13 and PostgreSQL 17 backend flagship focused on architecture, data integrity and operational discipline.

Engineering decisions: versioned REST API, ULIDs, database constraints, transactional enrollment rules, row locking for concurrency safety, application-service boundaries, integration tests, OpenAPI, Docker, GitHub Actions, Dependabot, ADRs, security policy and threat modeling.

What it demonstrates: concurrency-aware domain design, integrity enforced close to the data, explicit architecture decisions and production-readiness thinking without unnecessary infrastructure.

Framework-free PHP REST API demonstrating routing, PDO, repositories, services, validation, bearer authentication and JSON APIs.

Older repositories remain available to show technical progression across PHP, CodeIgniter, Symfony, integrations, data processing and web applications.

Professional work and technical implementation across:

• LLM integration and provider abstraction
• prompt engineering
• embeddings and semantic retrieval
• Model Context Protocol and tool integration
• recommendation systems
• AI-enabled backend systems
• observability and failure handling
• AI Security and Security by Design

Repositories that incorporate externally authored source material preserve explicit attribution and licensing boundaries and are kept separate from original flagship work.

Through Felix Studio, I have delivered custom technology for companies and entrepreneurs across Brazil since 2014.

The company publicly presents work across websites, e-commerce, web systems, business platforms, automation, mobile-oriented solutions, integrations, system modernization, SEO/GEO and Applied AI.

Selected client contexts publicly presented by Felix Studio include Medical Laudos, Laudos Online, Now Group, X Bell Tec, Cripto Solutions, Transvolga and iTuti.

See selected client delivery contexts

• Business context first: architecture should solve a real delivery or operational problem.
• Integrity over convenience: important invariants belong in transactions, constraints and explicit domain rules.
• Reliability is designed: failure paths, retries, timeouts and observability are part of the system, not afterthoughts.
• Security is architectural: credentials, privacy, authentication and trust boundaries are treated as design concerns.
• Evidence over claims: tests, CI, ADRs, threat models and reproducible environments are stronger than technology lists.
• Complexity must earn its place: distributed or asynchronous patterns are introduced only when the problem justifies them.

• Ongoing postgraduate specialization in Software Engineering in Applied AI, Centro Universitário Anhanguera / UNIPDS
• B.Sc. in Information Systems, Faculdade UNA Contagem, 2024
• Technical Degree in Information Technology, FUNEC, 2018

felixstudio.com.br · LinkedIn · bielfelix@icloud.com