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English
$
USD
I will fix any java or spring boot issue, build apis, debug errors and optimize code
Carlos G
About this gig
Is your Java project breaking, throwing weird errors, or acting like it has a life of its own?
Dont worry I can fix anything in Java.
I specialize in Java & Spring Boot, but I also handle full-stack, databases, APIs, architecture, and more:
What I can do for you in Java (pretty much everything):
- Fix ANY Java error (runtime, compile-time, logic issues)
- Debugging deep backend problems
- Build or repair Spring Boot services, microservices & modules
- Create REST APIs, controllers, services, repositories
- Implement JWT, Spring Security, Roles, OAuth2
- Integrate external APIs, microservices, messaging systems
- Work with Maven / Gradle, multi-module apps
- Handle Java Streams, Lambdas, Collections, Generics
- Optimize performance, refactor code & improve architecture
- Build full CRUD operations (backend or full stack)
- Multithreading, concurrency, executors, async tasks
- File handling, sockets, networking, serialization
- JPA, Hibernate, queries, relationships, migrations
- MySQL setup, optimization, schema redesign
- Unit tests & integration tests (JUnit, Mockito)
- Clean code, SOLID, design patterns (Singleton, Factory, Builder, etc.)
- UML diagrams, use-case docs & software architecture
- BPMN process modelin
Get to know Carlos G
Carlos G
Backend developer
- FromMexico
- Member sinceNov 2025
- Avg. response time1 hour
- Last delivery1 month
Languages
English, Spanish, German
I’m a software developer focused on building clean, scalable, and efficient solutions. I work with Java, Spring Boot, Angular, and MySQL to create reliable web apps and APIs. I have experience with UML modeling, Figma UI design, automation scripts, and API testing with Postman. I use IntelliJ IDEA Ultimate and Git for professional workflows. I enjoy debugging, optimizing code, and delivering maintainable systems. One of my key projects involved extracting Amazon pricing data using the Keepa API. rech out me!!
Other Software Development Services I Offer
FAQ
What do you need to start working on my project?
Usually just your project files, a brief description of the issue, and any error messages or screenshots. For API or database work, access credentials may be required.
Can you fix my issue even if I don’t know what’s wrong?
Yes. I can analyze your code, identify the root cause, and provide a clean, working solution along with an explanation if requested.
Do you offer full-stack support?
Yes. I work with Java, Spring Boot, Angular, MySQL, REST APIs, UML, GitHub, Postman, and more—so I can help with backend, frontend, and database issues.
Can you work on university or academic projects?
Yes. I can assist with assignments, explain the code, and ensure you understand the solution.
Will you explain what you fixed?
If you want, I can provide detailed notes, comments, UML diagrams, or an explanation of what caused the issue and how it was solved.
Can you help set up my environment or tools?
Yes. I can assist with IntelliJ, Git/GitHub, Postman collections, local servers, MySQL setup, and project structure.
Do you handle API integrations or errors?
Absolutely. I can build, debug, optimize, or repair REST APIs—backend logic, endpoints, controllers, and database operations.
What if my project is very outdated or messy?
No problem. I can refactor, clean, and modernize your code to follow best practices and improve performance.
What if I’m not sure which service to select?
Just message me with a description of your problem. I’ll guide you to the right option or create a custom offer.
Can you work on projects in English and Spanish?
Yes. I can develop, debug, and document projects in both English and Spanish, depending on your preference.
