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English
$
USD
I will fix, upgrade or modernize your java application
Erick P
5.0
5.0
What people loved about this freelancer
maxcrz
France
I am very satisfied with the service. The developer exceeded my expectations. Very professional, excellent communication, fast, competent, proactive. He perfectly...
maxcrz
France
3rd order, extremely satisfied, you can go ahead with complete confidence, very high level of competence, professionalism, responsiveness, and truly committed to the projects. Hard to find better. Thank you again
maxcrz
France
After several orders, I am impressed by the level of professionalism and expertise. Beyond the service, which I consider to be perfect in my own words, the...
About this gig
Is your Java application broken, outdated, or stuck on an old version?
I specialize in recovering, modernizing, and fixing Java applications from small personal projects to complex production systems with legacy codebases, outdated dependencies, and missing documentation.
With experience maintaining live production Java platforms integrated with external APIs, Docker deployments, and real-time data systems, I bring senior-level problem solving to every project.
I can help with:
- Updating Java projects from any version to Java 17, 21, or 25
- Fixing compilation errors, runtime crashes, and dependency conflicts
- Migrating build systems from Ant to Maven or Gradle
- Recovering abandoned or undocumented legacy projects
- Spring Boot, JavaFX, and Swing applications
- Database integration PostgreSQL, MySQL
Before ordering please share:
- Java version and build tool (Maven/Gradle/Ant)
- Error messages or logs
- Project files or repository link
If your project cannot reasonably be fixed within scope I will tell you honestly before any work begins.
Get to know Erick P
Erick P
Software Developer
- FromBrazil
- Member sinceFeb 2026
- Avg. response time1 hour
- Last deliveryabout 9 hours
Languages
English, Portuguese
Software developer specializing in Java, C++, JavaScript and PHP — with experience maintaining live production systems handling real users and real data.
I fix broken applications, modernize legacy codebases, build desktop applications, develop APIs, and deploy to production servers with Docker.
I work with projects most developers avoid — undocumented legacy code, complex integrations, and years of technical debt.
If your project can't be solved within scope, I'll tell you honestly before starting.
Other Software Development Services I Offer
FAQ
Do you write new applications from scratch?
This gig focuses on updating or fixing existing projects. New applications can be discussed separately.
What if my project can’t be fixed?
If the issue cannot reasonably be solved, I will let you know before proceeding.
Can you fix projects with no documentation?
Yes. Working with undocumented legacy codebases is something I do regularly and enjoy solving.
Can you migrate a project from Ant to Maven or Gradle?
Yes. Build system migration is included in the Standard and Premium packages and is one of the most impactful modernizations you can make to a legacy Java project.
Do you work with Java Swing or JavaFX desktop applications?
Yes. I have extensive experience with both Swing and JavaFX desktop applications including UI fixes, feature additions, and full modernization.
What information do you need before starting?
At minimum — your Java version, build tool, error messages or logs, and access to the project files via repository link or ZIP attachment.
Do you have experience with production systems?
Yes. I have hands-on experience maintaining and fixing live production Java applications handling real users and real data, including API integrations and Docker deployments.
Reviews
7 reviews for this Gig
| (7) | ||
| (0) | ||
| (0) | ||
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Rating Breakdown
- Seller communication level
- Quality of delivery
- Value of delivery
Sort By
Most relevant
M maxcrz
Repeat Client
France
I am very satisfied with the service. The developer exceeded my expectations. Very professional, excellent communication, fast, competent, proactive. He perfectly adapts to the needs and accomplishes them with astonishing skill. A true masterpiece. Thanks you.
$50-$100
Price
3 days
Duration
Helpful?M maxcrz
Repeat Client
France
3rd order, extremely satisfied, you can go ahead with complete confidence, very high level of competence, professionalism, responsiveness, and truly committed to the projects. Hard to find better. Thank you again
$50-$100
Price
2 days
Duration
Helpful?M maxcrz
Repeat Client
France
After several orders, I am impressed by the level of professionalism and expertise. Beyond the service, which I consider to be perfect in my own words, the communication is very proactive, and the result of my request exceeded my expectations. Thank you again.
$200-$400
Price
7 days
Duration
Helpful?M maxcrz
Repeat Client
France
Excellent, merci beaucoup
Up to $50
Price
1 day
Duration
Helpful?M maxcrz
Repeat Client
France
Excellent travail 4ème commande, rien à changé toujours une excellente prestation. Merci
$50-$100
Price
3 days
Duration
Helpful?
Reviews
7 reviews for this Gig
| (7) | ||
| (0) | ||
| (0) | ||
| (0) | ||
| (0) |
Rating Breakdown
- Seller communication level
- Quality of delivery
- Value of delivery
Sort By
Most relevant
M maxcrz
Repeat Client
France
I am very satisfied with the service. The developer exceeded my expectations. Very professional, excellent communication, fast, competent, proactive. He perfectly adapts to the needs and accomplishes them with astonishing skill. A true masterpiece. Thanks you.
$50-$100
Price
3 days
Duration
Helpful?M maxcrz
Repeat Client
France
3rd order, extremely satisfied, you can go ahead with complete confidence, very high level of competence, professionalism, responsiveness, and truly committed to the projects. Hard to find better. Thank you again
$50-$100
Price
2 days
Duration
Helpful?M maxcrz
Repeat Client
France
After several orders, I am impressed by the level of professionalism and expertise. Beyond the service, which I consider to be perfect in my own words, the communication is very proactive, and the result of my request exceeded my expectations. Thank you again.
$200-$400
Price
7 days
Duration
Helpful?M maxcrz
Repeat Client
France
Excellent, merci beaucoup
Up to $50
Price
1 day
Duration
Helpful?M maxcrz
Repeat Client
France
Excellent travail 4ème commande, rien à changé toujours une excellente prestation. Merci
$50-$100
Price
3 days
Duration
Helpful?
