Trinh Long Vu Avatar
Trinh Long Vu
Trinh Long Vu Avatar
Available for Freelance
React & TypeScript UI
Java & Spring Boot APIs
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FREELANCE DEVELOPER POSITIONING

Building Responsive Web Applications & Robust Backend Systems

I am Trinh Long Vu, a freelance full-stack software developer specializing in React/TypeScript frontend development and Java/Spring Boot backend engineering.

My primary focus is providing client-oriented software solutions — whether that means building clean, responsive web user interfaces and dashboards from scratch, implementing high-throughput REST APIs, integrating financial market data feeds (such as the LongHub stock tracking platform), or fixing bugs and refactoring existing applications.

I emphasize clean code structure, modern web standards (React 18, TypeScript, Vite, Tailwind CSS), and reliable backend architecture (Java 21, Spring Boot, PostgreSQL, OpenAPI, Redis, Kafka).

Career History & Track Record

Engineering experience across enterprise banking modules, microservices, and API platforms.

React/TypeScript & Java/Spring Boot Freelance Developer

Independent Freelance Practice — Remote / Freelance
2024 — Present

Delivering end-to-end web applications, React frontend implementations, Spring Boot REST APIs, and database engineering solutions for clients.

  • Developed responsive React/TypeScript frontend applications, financial dashboards, and SaaS administrative interfaces.
  • Built scalable Java 21 & Spring Boot RESTful APIs following contract-first OpenAPI specifications.
  • Designed relational database schemas in PostgreSQL, utilizing JPA/Hibernate for optimized query execution.
  • Integrated identity security with Keycloak (OAuth2/JWT) and asynchronous streaming pipelines with Kafka & WebSockets.
  • Provided bug fixing, UI refactoring, performance tuning, and third-party API integrations for existing client codebases.
ReactTypeScriptJavaSpring BootPostgreSQLTailwind CSSViteRedisDockerGit

Java & Spring Boot Developer

Enterprise Core Banking Platform — Remote / Project Contract
11/2024 — Present

Contributed to building enterprise-level banking systems featuring multi-tier transaction approval workflows and high-performance APIs.

  • Built and optimized RESTful APIs using Spring Boot adhering to OpenAPI standards.
  • Developed multi-level approval workflows and transaction state machines for enterprise business logic.
  • Designed complete CRUD logic, data mapping, file import validation, and standardized error handling pipelines.
  • Optimized PostgreSQL queries and JPA/Hibernate mappings to maintain sub-second response times under peak request loads.
JavaSpring BootPostgreSQLJPA/HibernateOpenAPI/SwaggerGit

Engineering Principles & Values

React & TypeScript UI Engineering

Crafting responsive, component-driven web interfaces, SaaS dashboards, and tabular applications with clean state management, Vite, and Tailwind CSS.

Java & Spring Boot Backend Systems

Architecting robust RESTful microservices, JPA/Hibernate ORM mappings, multi-level approval workflows, and OpenAPI 3.0 specs.

Full-Stack Integration & APIs

Seamlessly connecting React frontends with Spring Boot backends, PostgreSQL databases, Keycloak OAuth2 authentication, and third-party APIs.

Performance & Database Optimization

Optimizing PostgreSQL database queries, implementing Redis caching layers, and troubleshooting complex application bottlenecks for production reliability.