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I need an experienced backend developer to eliminate a set of stubborn bugs in our Java-based web application. The codebase runs on Spring Boot and follows a microservice-style layout, but two pain points remain: • Backend errors – intermittent 500 responses, stack-trace bursts in the logs, and occasional transaction rollbacks. • Performance problems – slow API endpoints under load and high memory consumption during peak traffic. Your task is to: 1. Identify the root causes of these backend errors and performance problems through log analysis, profiling, and unit/integration testing. 2. Implement clean, reliable code fixes that align with our existing Spring Boot standards (Java 17, Spring Boot 3.x, Maven). 3. Add or update tests to prove the issues are resolved and prevent regressions. 4. Provide a concise change log and recommendations for any additional optimizations or refactors. We deploy to AWS using Docker and GitLab CI/CD; familiarity with these tools is helpful, though not mandatory. Clear, proactive communication is essential—I value quick check-ins and explanations in plain language so everyone on the team stays aligned. Please outline a brief plan of attack, highlight similar bug-fixing projects you’ve completed, and estimate how long you’ll need once you have repo access. I’m ready to grant access and start as soon as we agree on the approach.
Project ID: 40438866
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37 freelancers are bidding on average $41 USD/hour for this job

With over a decade of experience in high-performance full-stack architecture and high-scale systems, I understand the importance of resolving backend bugs and performance issues swiftly and effectively. Your project goal of eliminating stubborn bugs in your Java Spring Boot web application aligns perfectly with my expertise in tackling complex technical challenges. To address the intermittent 500 errors and performance bottlenecks, I propose a comprehensive approach that includes rigorous log analysis, profiling, and thorough testing to pinpoint and resolve root causes. Drawing from my experience in handling high-traffic systems and optimizing code for maximum efficiency, I am confident in my ability to deliver clean, reliable fixes that meet your Spring Boot standards. By leveraging my past success in resolving similar issues for large-scale applications, such as the successful scaling of a Telegram Mini App to over 1 million users, I am well-equipped to handle the complexities of your project with precision and expertise. I invite you to reach out to discuss the specifics of your project further and elaborate on a strategic plan of attack. Let's collaborate to ensure a seamless resolution to your backend challenges.
$40 USD in 15 days
8.1
8.1

With over a decade of experience in Java and JavaScript, along with my team's track record of producing robust, efficient code for complex systems, we are the ideal award-winning bevy for this Java-based project. Spring Boot may layout our code, but it is our proficiency in debugging that sets us apart. We recognize what triggers "Backend errors" and tackle them from their roots proficiently. Our meticulous approach includes log analysis, profiling, and thorough testing to ensure no stone is left unturned in this debugging expedition. Moreover, our bug-fixing prowess has been deployed across multiple microservice applications and it comes customized with an upgrade to the current version which implies bugs like "intermittent 500 errors" (related to resource allocation) and "stack-trace bursts" (rooted in faulty communication between microservices) would have already vanished once we're done here. AWS deployment through Docker and GitLab CI/CD is a familiar path we've traversed myriad times as well. While we can steadfast from the first click, rapid sprints won't compromise our effective feed-back loops or concise explanations. You will be updated on our progress regularly and should the need arise, we'll explain complex issues in clear terms- HVAC for developers! Let's get access-granted so we can get this show on the road /debug
$250 USD in 40 days
5.8
5.8

You need someone who can quickly find why 500s and transaction rollbacks appear under load and stop the memory spikes without rewriting the app. Those failures usually come from unhandled exceptions, incorrect transaction boundaries, or a leaking cache/thread pool that only shows under production load. I recently tracked down intermittent 500s and a memory leak in a Spring Boot payments microservice: log correlation, heap dump analysis, fixed a misused transactional boundary, and added targeted integration tests to prevent regressions. Plan of attack - Run focused log analysis and reproduce spikes with a profiler and load tests - Fix root causes in code and adjust transaction handling or thread pools - Add unit and integration tests that replicate the failure paths - Deliver a concise changelog and a short list of follow up optimizations Estimated time after repo access and sample logs: about 3 to 5 days to diagnose, implement fixes, and add tests. Please grant repo access and attach a recent log snippet or one failing request example so I can start with the most affected service. Which service shows the most 500s?
$37.50 USD in 7 days
4.8
4.8

Hi, this is Kris from McKinney, Texas, I've reviewed your project requirements and understand the key challenges you are facing with the intermittent backend errors and performance issues in your Java Spring Boot application. The need to identify root causes, implement clean code fixes, and enhance testing to ensure stability and performance are crucial aspects of this project. My approach involves thorough log analysis, profiling, and testing to pinpoint and resolve the bugs effectively. I will adhere to your Spring Boot standards, provide detailed change logs, and suggest optimizations for long-term stability. A few additional questions: Q1: Could you provide access to the repository for a more in-depth analysis? Q2: Are there specific endpoints or modules where the performance issues are more pronounced? Q3: Do you have any specific testing frameworks or tools in place that you prefer? Best regards, Kris Kramer
$38 USD in 40 days
4.7
4.7

With over a decade of experience as a full stack developer matching perfectly with the technologies for your project, I am confident in my ability to find and fix the bugs that have been causing your team headaches. My expertise in Backend Development, Docker, Java, JavaScript and Software Architecture are specifically tailored to meet the demands of your project. Using my deep understanding of Spring Boot and the microservice-style layout, I will diligently tackle these issues through log analysis, profiling and rigorous testing. One of my greatest strengths lies in effective troubleshooting and diagnostics. I have equivalent experience in optimizing performance and dealing with memory-consuming applications under peak traffic. Implementing clean, reliable code fixes that align with your existing standards is paramount - and something I prioritize highly. As a bonus, I'm also proficient with GitLab CI/CD tools which facilitate smooth deployment. Moreover, my remote working experience pairs well with our need for clear, open lines of communication during your AWS Docker-based project. In this regard, I believe that transparency is key - so quick check-ins and explanations in plain language will be an essential part of our collaboration. Therefore, with these skills in mind, you can rest assured knowing that you are hiring not just a developer but a committed partner that focuses on delivering results while keeping everyone aligned along the way.
$30 USD in 40 days
4.4
4.4

With over a decade of experience in backend development, especially in Java and Spring Boot, I am confident that I can effectively address and eliminate the persistent errors and bottlenecks in your web application. My work approaches, such as log analysis, profiling, unit testing, and ensuring code compliance with existing Spring Boot standards (Java 17, Spring Boot 3.x, Maven), will specifically target the root causes of the issues that you're facing. Having worked on multiple bug-fixing projects previously with reported challenges similar to yours - intermittent backend errors, transaction rollbacks, slow API endpoints under load - I have developed not just a deep understanding but also efficient problem-solving strategies. This is coupled with my skill set in GitLab CI/CD and AWS deployment with Docker. Furthermore, my commitment to clear and proactive communication will ensure you are regularly updated and aligned with the progress made. It would be my pleasure to leave you with solid and well-documented fixes while providing any additional recommendations for optimization or refactoring that could enhance performance and maintainability. Let's collaborate on this project for viable results!
$38 USD in 40 days
3.9
3.9

Hi, ⭐15+ Yrs Sr Developer here⭐ I have strong experience debugging Java 17, Spring Boot 3.x, Maven, Docker-based microservices, and production backend systems with intermittent 500 errors and performance issues. My approach would be to first review logs, reproduce the failures, inspect transaction boundaries, profile slow endpoints, and check memory usage under load before making any code changes. I’ll then apply clean fixes, improve exception handling where needed, optimize queries or service logic, and add unit/integration tests to prevent the same bugs from returning. I’m also comfortable with AWS, Docker, and GitLab CI/CD, so I can work within your existing deployment workflow smoothly. Once I have repo access and logs, I can give a precise estimate, but I usually start with a focused diagnostic pass followed by prioritized fixes and a clear change log. If you think I am a good fit, feel free to ping me anytime. — GAZMIR
$30 USD in 40 days
3.2
3.2

I can help you quickly identify and resolve the stubborn bugs in your Java Spring Boot application, with a focus on stability, performance, and clean code. I’ve worked extensively on backend services where subtle issues in configuration, threading, or data handling caused unpredictable behavior. My experience includes debugging and hardening Spring Boot microservices, REST APIs, and integrations with databases and third-party systems, often in production environments where downtime is costly. I’d start by reproducing each bug reliably, reviewing logs and stack traces, then isolating root causes in code, configs, or dependencies, and adding targeted tests to prevent regressions. What’s the biggest issue you’re seeing right now—errors, performance problems, or inconsistent behavior?
$37.50 USD in 7 days
3.8
3.8

Hello, As a result of a detailed review of your project requirements, I fully understand the scope and expectations. You need an experienced backend developer to diagnose and fix Spring Boot errors, transaction rollbacks, slow APIs, and memory issues. I have experience handling similar Java backend debugging and performance optimization projects and I'm available to start right now. I bring strong expertise in Java 17, Spring Boot 3.x, Maven, Microservices, Docker, Software Architecture, Backend Development, GitLab CI/CD, and AWS deployments. My approach would be to first review logs and reproduce the 500 errors, then profile slow endpoints and memory usage, identify root causes, apply clean fixes, and add/update unit and integration tests to prevent regressions. I can also provide a clear change log and practical recommendations for future optimizations. I have a couple of quick questions. • Do you already have error logs or APM traces available? • Are the slow endpoints related to database queries, external APIs, or internal service calls? I would be glad to discuss further details and am ready to start immediately. Looking forward to hearing from you. Best regards, Carlos
$25 USD in 40 days
2.6
2.6

Hello, The main engineering challenge lies in diagnosing intermittent 500 errors and understanding the underlying causes of transaction rollbacks. Another complexity is optimizing API performance under load while managing high memory consumption during peak traffic. Could you clarify the current logging and monitoring setup? Are there specific endpoints that exhibit performance issues, or is it a broader concern across the application? Additionally, what is the testing strategy in place to validate the fixes and ensure no regressions occur? I am ready to dive into the codebase and collaborate effectively.
$25 USD in 40 days
2.5
2.5

Hi there, I'm Cora May, and I’ve spent a lot of time untangling stubborn Spring Boot production issues where the logs look chaotic but the root cause is usually consistent. For your microservice-style Java 17 / Spring Boot 3.x app, I’ll start by correlating intermittent 500s with request traces, DB/transaction events, and log stack-trace bursts, then reproduce them with targeted unit + integration tests. In parallel, I’ll profile the slow endpoints under load to pinpoint bottlenecks (blocking calls, N+1 queries, thread pool starvation, inefficient serialization, and GC/memory spikes), and implement clean, standards-aligned fixes using your existing conventions. Next, I’ll add/update tests that specifically cover the failure modes and performance regressions so you don’t relive this pain later. Once the issues are resolved, I’ll deliver a concise change log plus practical recommendations for additional optimizations or refactors, plain language included for the whole team. Quick questions: are you seeing any specific services/endpoints that account for most 500s during peak traffic, and do you have DB details (e.g., Postgres/MySQL) plus current connection pool settings?
$25 USD in 29 days
2.6
2.6

Hello Sir, As a seasoned Senior Full Stack & DevOps Engineer, I've spent the past 9+ years tackling complex backend issues across various tech stacks and deploying on various cloud infrastructures - including Docker which you use. My in-depth knowledge of Backend Development and familiarity with Spring Boot (Java 17, Spring Boot 3.x) align closely with your project's needs. Specifically, my experience focuses heavily on clean code fixes, automated testing to prove issue-resolution, and optimization strategies to prevent future regressions. One of my recent projects involved dealing with backend bugs similar to what you described. The key takeaways were rapid identification of problems through meticulous log analysis, thorough system profiling, and comprehensive unit/integration testing that nailed the root causes. Guestimating, my timeline should be within 10-15 working days, provided I gain access to the repository soon. My approach is all about ensuring scalable and maintainable software systems from the get-go. I will prioritize precisely locating your stubborn issues and implement appropriate fixes while adhering strictly to your existing Spring Boot standards and utilising optimal coding practices. Whenever necessary for better clarifications in understanding or guidance on new recommendations for refactoring or optimization purposes, I'm proactive in reaching out for quick check-ins - keeping everyone aligned on progress updates. Thanks! John
$50 USD in 31 days
2.3
2.3

Hi! I totally get how frustrating those 500 errors and performance hiccups can be. Let’s tackle this head-on. First up, I’d dive into the logs to pinpoint what’s causing those backend issues. A thorough profiling of the application should help identify the slow API endpoints and memory issues during peak times. I’ll also run unit and integration tests to ensure we get a solid grasp on the problems. I’ve worked on similar bug-fixing projects in the past, dealing with Spring Boot applications, so I know how to implement fixes that are clean and follow best practices. In about 5 days, I could deliver initial fixes and a summary of changes, along with any additional optimization recommendations to keep things running smoothly. Quick question,do you have specific testing frameworks in place that you want me to follow? Let’s make sure we sync up before diving in. best regards Walled Saleem
$26 USD in 40 days
2.1
2.1

Hi, The goal is to resolve backend errors and performance issues in your Java Spring Boot web application. The root causes of intermittent 500 responses and slow API endpoints will be identified through thorough log analysis and testing. Clean code fixes will be implemented in alignment with Spring Boot standards, ensuring reliability. Tests will be added or updated to validate the fixes and prevent regressions. A concise change log and optimization recommendations will be provided for continuous improvement. With over 6 years of experience in Java, JavaScript, and Software Architecture, I have successfully resolved similar bugs in complex microservice applications. My certification in backend development further validates my expertise in this area. I have a few questions about the project. Let's discuss further via chat to align on the approach. My time zone is flexible, so I can easily work around yours. Cheer, Dax.M
$40 USD in 40 days
2.0
2.0

With over two decades of experience in full-stack development, DemiVision is well-prepared to tackle your stubborn Java Spring Boot bugs and optimize your web application's performance. Our extensive expertise spans reliable backend development, which aligns perfectly with your requirements for bug fixing and increasing speed and efficiency. Additionally, our familiarity with Docker and GitLab CI/CD allows for a seamless integration of our fixes into your AWS deployment. As a diligent team, we prioritize clean coding practices, maintainable solutions, and rigorous testing. We will thoroughly analyze logs, profile the system, introduce necessary unit and integration tests, and provide a comprehensive change log to ensure that the issues are not only resolved but prevent regression as well. We understand the importance of clear communication in keeping a project on-track. Hence, we value quick check-ins and explaining complex technicalities in plain language so that everyone on the team stays informed. Moreover, being a-continuous learner approach is guaranteed as we will also provide recommendations for optimizations or refactors beyond what you outlined in the project description. Given this opportunity to work with you on eliminating these pesky bugs and optimizing your application's performance, you can count on us for delivering sustainable growth through innovation.
$38 USD in 14 days
1.4
1.4

Hi, This is Abhiram from UK. I understand the critical need to resolve the backend errors and performance issues in your Java Spring Boot application. With experience in similar projects, I aim to analyze logs, conduct testing, and deliver clean code fixes aligned with Spring Boot standards. Let me ask you a couple of things so I understand it better: Q1- Have you conducted any initial analysis on the intermittent 500 responses? Q2- How important is real-time monitoring for the performance enhancements? Looking forward to discussing the details further to ensure a successful resolution.
$28 USD in 40 days
1.1
1.1

Hi, I can help with fixing Java Spring Boot bugs. Core challenge: The backend errors and performance issues are intermittent and hard to pinpoint, with 500 responses, stack-trace bursts, and transaction rollbacks. Performance problems include slow API endpoints under load and high memory consumption during peak traffic. Common pitfalls I will avoid: - Ignoring log analysis and profiling for root cause identification - Not following Spring Boot standards in code fixes Workflow: Log analysis -> Unit/integration testing -> Clean code fixes -> Add tests to prove fixes Key decision: Clarify the exact root cause of the backend errors and performance issues. Quick questions: - What is the exact root cause of the intermittent 500 responses? - How can we optimize API endpoints for high traffic? - What specific roles or records need to be updated for the fix? - What edge cases should be tested to ensure no regressions?
$25 USD in 3 days
1.0
1.0

Hi, Intermittent 500s with transaction rollbacks in a Spring Boot microservice setup usually point to a handful of well-known culprits, and the combination of that plus memory pressure under load gives me a reasonable starting hypothesis before even seeing the code. Are the 500s tied to specific endpoints or random across the service, and is the high memory consumption gradual over time suggesting a leak, or does it spike under load and recover? Those two answers narrow the investigation significantly. Gradual memory growth in Spring Boot 3.x on Java 17 is often heap pressure from connection pool misconfiguration or unclosed resources, while load-correlated spikes usually point to inefficient queries or missing pagination on data-heavy endpoints. For the transaction rollbacks I'd start with the exception types being swallowed or rethrown, since Spring's rollback behaviour changes depending on whether the exception is checked or unchecked and how the transactional boundaries are defined across service calls. My approach would be log analysis first to find patterns, then profiling with async-profiler or heap dump analysis depending on what the logs suggest, then targeted fixes with regression tests added before closing each issue. Estimate a realistic timeline once I have repo access and can see the actual stack traces. Kind regards, Abel.
$38 USD in 40 days
0.0
0.0

⚠️ If you're not happy, you don’t pay. ⚠️ Hi there, Thank you for checking my proposal and sharing the detailed project brief. I can resolve the stubborn bugs in your Java-based web application built on Spring Boot, ensuring a seamless experience. I will deliver: • Root cause analysis through log analysis, profiling, and testing • Implementation of reliable code fixes in Java 17, Spring Boot 3.x, and Maven • Addition/update of tests for validation and prevention of regressions • Concise change log and optimization recommendations You will also receive: • Clear documentation and recommendations • Post-delivery support for alignment and clarity I am confident I can execute your vision professionally and efficiently. Looking forward to discussing the plan and next steps. Best regards, Chirag.
$50 USD in 7 days
0.0
0.0

Hello, I understand the importance of eliminating stubborn bugs in a Java-based web application like yours. With my extensive experience in backend development, including working with Java and Spring Boot, I am well-equipped to tackle the backend errors and performance issues you are facing. I am familiar with log analysis, profiling, and testing to identify root causes effectively. Here’s how I’ll approach your project: ✔ Identify and resolve root causes of backend errors ✔ Address performance problems through clean code fixes ✔ Update tests to ensure issue resolution ✔ Provide a comprehensive change log and optimization recommendations My goal is to deliver a reliable, polished solution that aligns with your standards and boosts performance. I look forward to working with you to achieve these objectives. Best regards, Manthan
$25 USD in 30 days
0.0
0.0

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