Hallef Lucas Bernardo Da Silva

Java Developer
3repositories checked by code analysis
3projects
2roles confirmed by code
Bachelor’sCentro Universitário Internacional (UNINTER)

Overview

Java backend developer at a junior level specializing in building simple REST CRUD APIs with Spring Boot. The strongest proven skill is implementing REST endpoints, DTO mapping and basic validation as shown in PedidoController.java and ProdutoController.java. There is little evidence of production concerns such as migrations, automated tests, authentication or performance tuning in public code.

Timeline

Centro Universitário Internacional (UNINTER)
Bachelor's Degree · Systems Analysis and Development
2024–2027 Salvador, Bahia

Projects

Curitiba
Created a responsive informational web page with navigation, an image gallery, and interactive content sections. Used Bootstrap for layout and styling, and added dynamic UI behavior with jQuery. Focused on building a clean, user-friendly front-end interface.
BaoziStore
Developed a Java backend focused on REST API design and client-server communication. Implemented backend logic exposed through HTTP endpoints. Practiced structuring application code to support API-driven functionality.
Pineefy
Built an affiliate SaaS platform with user authentication, an admin dashboard, and affiliate tracking features. Developed a responsive full-stack experience using Next.js and React. Integrated Firebase Authentication and Cloud Firestore for data handling, and used Recharts to present analytics.

Technical skills

Languages
4
Java
JavaScript
Python
SQL
Java
4
Spring Boot
Spring Data JPA
Spring MVC
Jackson
Frontend
4
React.js
Bootstrap
Next.js
Tailwind CSS
Other
10
FastAPI
Firebase
JQuery
GitHub
Rest API
Firestore
Recharts
Docker
Git
PostCSS
Backend Developer Code level: Junior Confidence: Medium API Engineer
Java backend developer at a junior level specializing in building simple REST CRUD APIs with Spring Boot. The strongest proven skill is implementing REST endpoints, DTO mapping and basic validation as shown in PedidoController.java and ProdutoController.java. There is little evidence of production concerns such as migrations, automated tests, authentication or performance tuning in public code.
API Design
3/10
How well APIs are designed
Basic REST API design with DTOs, validation and consistent error mapping is present, but no versioning, pagination, idempotency or documented error contract beyond a simple exception handler.
Evidence
euhallef/baozistore/baozistore/baozistore/src/main/java/com/uninter/baozistore/controller/PedidoController.java euhallef/baozistore/baozistore/baozistore/src/main/java/com/uninter/baozistore/controller/ProdutoController.java euhallef/baozistore/baozistore/baozistore/src/main/java/com/uninter/baozistore/dto/PedidoResponseDTO.java
Data Layer & Database
2/10
Working with databases
Uses JPA entities and Spring Data repositories with validation annotations, but no migration history, explicit transaction boundaries, custom SQL tuning or attention to N+1 patterns.
Evidence
euhallef/baozistore/baozistore/baozistore/src/main/java/com/uninter/baozistore/model/Pedido.java euhallef/baozistore/baozistore/baozistore/src/main/java/com/uninter/baozistore/model/Produto.java euhallef/baozistore/baozistore/baozistore/src/main/java/com/uninter/baozistore/repository/ProdutoRepository.java
Scalability & Performance
1/10
Handling load and speed
No explicit scalability or performance patterns such as caching, async/queueing, rate limiting or connection tuning are present; code is synchronous CRUD against repositories.
Evidence
euhallef/baozistore/baozistore/baozistore/src/main/java/com/uninter/baozistore/controller/PedidoController.java euhallef/baozistore/baozistore/baozistore/src/main/java/com/uninter/baozistore/controller/ProdutoController.java
System Architecture
2/10
Overall system structure
Clear single-service monolithic layout (controllers, models, repositories, dto) suitable for small apps; lacks multi-service decomposition, config/secret management or resilience-oriented boundaries.
Evidence
euhallef/baozistore/baozistore/baozistore/src/main/java/com/uninter/baozistore/controller/ProdutoController.java euhallef/baozistore/baozistore/baozistore/src/main/java/com/uninter/baozistore/dto/PedidoResponseDTO.java
Security & Auth
2/10
Protecting data and access
Input validation via jakarta.validation and a global exception handler are used, which is good practice, but there is no authentication/authorization, token lifecycle or explicit secrets hygiene shown.
Evidence
euhallef/baozistore/baozistore/baozistore/src/main/java/com/uninter/baozistore/dto/PedidoRequestDTO.java euhallef/baozistore/baozistore/baozistore/src/main/java/com/uninter/baozistore/exception/ApiExceptionHandler.java euhallef/baozistore/baozistore/baozistore/src/main/java/com/uninter/baozistore/controller/PedidoController.java
Reliability & Observability
2/10
Stability and monitoring
Basic reliability: a centralized exception handler and use of ResponseEntity are present, but there is no structured logging, correlation ids, timeouts, retries with backoff, metrics or graceful shutdown handling.
Evidence
euhallef/baozistore/baozistore/baozistore/src/main/java/com/uninter/baozistore/exception/ApiExceptionHandler.java euhallef/baozistore/baozistore/baozistore/src/main/java/com/uninter/baozistore/controller/PedidoController.java
Expertise
Java· Junior
Microservices & API Architecture· Junior
Databases & Vector Storage· Junior
Industries
Commerce· Junior
Technologies
Python
Java· since 2025 · Junior
Rest API
Jackson
Spring Boot
FastAPI
Spring MVC
Spring Data JPA
Recommendations
  • Develop small-to-medium internal REST services and CRUD features for commerce prototypes or MVPs using Spring Boot.
  • Add unit and integration tests plus a migration tool (Flyway/Liquibase) to increase reliability and production readiness.
  • Implement authentication/authorization and structured logging/metrics for APIs to prepare services for real deployments.
  • Practice schema evolution and transaction handling by adding explicit transactional boundaries and addressing potential N+1 patterns.
Repositories
The developer's experience in this domain has been verified based on AI analysis of the following repositories:
Estruturas-de-Controle-JAVA baozistore
Frontend Developer Code level: Intern Confidence: Low UI Engineer
Frontend UI engineer (junior) with practical exposure to legacy Bootstrap and jQuery integrations. The strongest proven artifact is the presence and integration of Bootstrap and jQuery behavior as evidenced by bootstrap/js/bootstrap.js and jquery.js in the code. There is no authored application logic, custom components, async state handling or tests available to evaluate higher-level frontend engineering skills.
UI Component Architecture
How interface parts are built
Not evidenced in public code
Responsive & Cross-browser
Works on all screens and browsers
Not evidenced in public code
Performance Optimization
Speed of the interface
Not evidenced in public code
Accessibility & Semantics
Usable for everyone
Not evidenced in public code
State Management & Data Flow
Managing data in the app
Not evidenced in public code
UX & Visual Polish
Look and feel quality
Not evidenced in public code
Technologies
JavaScript
Tailwind CSS
Next.js
Bootstrap
Git
Docker
React.js
JQuery
PostCSS
Recharts
GitHub
Recommendations
  • Maintain and extend legacy Bootstrap/jQuery UIs - implement bug fixes, small feature changes and accessibility tweaks within the existing codebase.
  • Migrate incremental pieces to a component-based framework - extract isolated UI widgets and reimplement them as components in React, Vue or similar to modernize the stack.
  • Introduce front-end build and dependency management - remove checked-in vendor files, adopt a package manager (npm/pnpm) and add a bundler and linter configuration.
  • Add testing and CI - introduce automated UI tests (unit and basic integration), linting, and simple CI runs to improve reliability and enable refactoring.
Repositories
The developer's experience in this domain has been verified based on AI analysis of the following repositories:
fds.uninter

Job preferences

Work permits
Brazil
Citizenship
Brazil
Employment type
Full-Time
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