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I am looking for a Full Stack Developer to help fix UI and API integration issues in our existing application. The work includes resolving frontend bugs such as layout, responsiveness, and component errors. You will also fix backend API issues including failed requests, data mapping problems, and authentication or connectivity issues. The goal is to ensure smooth and reliable communication between the frontend and backend systems. This is a bug fix project with fixed price and a strict deadline of 1 day. I am looking for someone who can start immediately and deliver clean, production-ready fixes.
Project ID: 40416081
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Active 15 days ago
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Hi There , Good evening! I am skilled mobile coder with skills including JavaScript, PHP, Backend Development, Full Stack Development, Mobile App Development, MySQL, API Development and Frontend Development. Please send a message to discuss more regarding this project. With regards
$30 USD in 6 days
1.0
1.0
58 freelancers are bidding on average $47 USD for this job

I see you need an urgent fix for your UI and API issues within a tight 24-hour window. Since these bugs are impacting your current functionality, I can dive into the code immediately to identify the root cause and resolve the communication errors. My background includes over 15 years of experience handling full-stack troubleshooting, including PHP, JavaScript, and MySQL database management. I frequently repair broken site components and API integrations, so I am well-equipped to handle the specific technical challenges you are facing without needing extra time to figure out the environment. I have set my bid at $34.52 to get this resolved for you within your one-day deadline. Send me the project details or the relevant code snippets so I can start working on the fix right away.
$34.52 USD in 1 day
8.1
8.1

Hi, I have strong experience with Php, Laravel and Code ignitor. I’ll develop robust and secure web application just the way you want. I can handle any updates you need. You can check my reviews to see the quality of my work, I will share my previous application in private chat. Lets connect in chat so that We discuss further. With Regards, Sai
$30 USD in 1 day
7.7
7.7

I can quickly resolve your frontend UI bugs and backend API issues, ensuring smooth integration and stable performance within your 1-day deadline. I’m ready to start immediately and deliver clean, production-ready fixes. Best regards, Ihtsham
$40 USD in 1 day
7.0
7.0

As an experienced, full stack developer with extensive expertise in JavaScript, Mobile App Development, MySQL, and PHP, I'm uniquely positioned to tackle the UI and API bug fixes your application desperately needs. Drawing from more than a decade of building scalable and high-performance applications, solving problems, like layout inconsistencies and component errors, is my forte. In addition, I've demonstrated a proven ability to fix complex backend API issues including failed requests and data mapping problems while also resolving authentication or connectivity issues. I'm well-aware that you are working against a tight deadline of 1 day and I'm ready to dive in immediately. It's worth noting that punctuality is one of my strongest attributes; my past clients highlight my ability to deliver on-time without compromising quality. You can count on me for a clean, production-ready job that will ensure smooth communication between the front-end and back-end systems. Choose me for this project and it's not just my skills and experience you'll be leveraging but also my commitment to provide quick understanding of your requirements, fast response time, clear communication, as well as a robust end-to-end project handling capability. Join hands with me today and see your application become even better.
$40 USD in 2 days
7.1
7.1

With over a decade in the industry, I'm well-versed in handling exactly the kind of challenges your project presents. My extensive experience in front-end development will allow me to tackle UI bugs with ease, from layout inconsistencies to component errors. On the back end, my proficiency in PHP and MySQL make me adept at identifying and resolving any issues related to API integration, be it failed requests or data mapping problems. I'm keen on more than just 'getting it done'. My solutions have always aligned functionality with security. On top of that, the attentive post-project support I provide goes a long way towards ensuring measures are in place to prevent future issues. With your trust in me today; let me turn your current project into an emblematic success story in my 100+ strong portfolio!
$49 USD in 1 day
6.4
6.4

Hi there, I understand this is a live app with PHP/MySQL backend and JavaScript frontend where layout/responsiveness and failing API requests (data mapping, auth/connectivity) are breaking UX; I can start immediately and deliver production-safe fixes within 1 day. - Fix frontend: correct CSS layout, responsive breakpoints, and React/Vue/vanilla component errors; cross-device verification and Chrome/Safari/Firefox checks - Fix backend APIs: inspect and patch PHP endpoints, correct MySQL queries and data mapping, restore authentication flow (session/JWT) and retry/timeout handling - Optional: small mobile WebView adjustments or API payload contract documentation if required - Risk/QA: backup checkpoint, staged deployment with post-fix validation and rollback plan Skills: ✅ PHP ✅ MySQL ✅ REST API troubleshooting ✅ JavaScript/CSS responsiveness ✅ cPanel/VPS deployment & hosting ✅ Post-fix validation & monitoring Certificates: ✅ Microsoft® Certified: MCSA | MCSE | MCT ✅ cPanel® & WHM Certified CWSA-2 Available to start immediately. Is this already running on a live production server? $30 , 1 day. Best regards,
$30 USD in 1 day
5.8
5.8

Hello, I came across your Urgent UI & API Bug Fix Needed (1 Day Delivery) and I am very interested in working with you. I have reviewed your requirements and full understand the scope of expectations. I specialize in PHP, JavaScript, Mobile App Development, MySQL, Full Stack Development, Backend Development, Frontend Development, API Development, and have successfully delivered similar projects before. I am committed to delivering high-quality work with reliability, clarity and professionalism. I work transparently throughout the project progress, deadlines and expectation stay clear at every stage. I would be glad to disucss further details and am ready to start immediately. Looking forward to hearing from you. Regards. Anum
$40 USD in 7 days
5.3
5.3

Hello, I can start immediately and fix your UI and API integration issues within the 1 day deadline. I will resolve frontend bugs including layout, responsiveness, and component errors. I will debug and fix backend API issues such as failed requests, data mapping, and authentication problems. I will ensure smooth and reliable communication between frontend and backend. All fixes will be clean, tested, and production ready. I have strong full stack experience and can deliver quickly under tight deadlines.
$50 USD in 1 day
5.4
5.4

As a competitive and experienced Full Stack Developer, I can assure you that my expertise matches your project's requirements to perfection! With my strong command over JavaScript, MySQL, and PHP, I have successfully undertaken projects of similar nature, diagnosing and providing clean fixes for bugs ranging from frontend layout issues to backend API problems. What sets me apart is not only my proficiency with a wide range of languages and frameworks such as Node.js, React.js, React Native but also my ability to adapt quickly to new technologies like your application's stack. Furthermore, I bring over 7 years of experience in software development to the table, empowering me with the keen attention to detail and swift problem-solving skills vital for time-sensitive projects such as yours. Throughout my career, my focus has always been on client satisfaction and delivering praiseworthy results within deadlines. When you work with me, you're benefiting not only from my extensive skillset but also from an individual who genuinely cares about your success. Let's get started on resolving these UI and API integration bugs; I'm ready to dive in straight away and help you achieve the smooth and reliable communication needed for efficient system functionality.
$30 USD in 7 days
6.5
6.5

I have handled several high-pressure, 24-hour turnarounds for full-stack environments where legacy API debt was breaking the frontend state. I understand the urgency of getting your UI back in sync with the backend, especially when critical user-facing features are hanging on failed requests. My experience in deep-level debugging of asynchronous data flows ensures I can jump straight into your codebase, replicate the errors, and identify the specific bottleneck without a long onboarding period. I focus on immediate resolution without compromising the underlying system architecture, ensuring your application is fully operational by your strict deadline. To resolve this within your one-day window, I will audit the network layer to isolate whether the failures stem from schema mismatches, CORS issues, or unhandled 500 series responses. Once the root cause is mapped, I’ll implement robust error handling and state management updates—using tools like Axios interceptors or specialized hooks—to ensure the UI reflects real-time data accurately. I will also perform quick regression testing on the affected endpoints to guarantee that the fix doesn't trigger side effects elsewhere. My approach prioritizes clean, modular code that addresses the immediate bugs while hardening the integration against future failures. I am ready to begin the diagnostic phase immediately upon hire. Do you have documentation for the API, or should I proceed by inspecting the integration layer? Are there specific UI components failing, or is this a global connectivity issue? I am available to start now and can jump on a call to walk through the code. Let's connect so I can hit your delivery goal.
$49 USD in 21 days
5.0
5.0

Greetings, I see you're looking for a Full Stack Developer to tackle some urgent UI and API bugs in your application. It sounds like you need someone who can jump in right away to fix frontend issues like layout and responsiveness, as well as backend problems with API requests and data mapping. My approach would be to thoroughly analyze the existing application to identify the root causes of these issues and implement clean, effective solutions that ensure smooth communication between the frontend and backend. With my experience in PHP, JavaScript, and API development, I can swiftly resolve these bugs and enhance the overall user experience. I’m committed to delivering production-ready fixes that meet your needs efficiently. Best regards, Muhammad Arshman
$42 USD in 4 days
4.7
4.7

Greetings, I can confidently handle this Full Stack Developer role and assist in resolving UI and API integration issues within your existing application. Being a Senior Full Stack Developer, I have a proven track record of successfully fixing frontend bugs related to layout, responsiveness, and component errors, as well as backend API issues like failed requests, data mapping problems, and authentication/connectivity issues. I invite you to chat on freelancer.com and review my profile for more details. I will deliver: - Swift resolution of frontend bugs and backend API issues - Ensuring smooth communication between frontend and backend systems - Clean, production-ready fixes for seamless operation For high-quality work within budget, message me on freelancer.com. Regards, Moeed.
$30 USD in 1 day
4.9
4.9

Hello, I came across your project and it immediately caught my attention. We went through your project description and it seems like our team is a great fit for this job. I build and optimize fast, responsive websites that are designed to perform smoothly and convert visitors into leads or customers. I’d love to discuss your project in more detail and get started right away. Best regards, Khadija Amin freelancer.com/u/khadijaamin9
$36 USD in 3 days
4.2
4.2

I won’t just patch bugs—I’ll identify root causes so the same issues don’t reappear after delivery. I can start immediately and focus on stabilizing both frontend and backend within your 1-day deadline. I’ll fix UI issues (layout, responsiveness, component errors) and resolve API problems (failed requests, data mapping, auth, connectivity), ensuring clean communication between layers. I’ll also test critical flows end-to-end so everything works reliably in production. You’ll get clean, structured fixes with quick handover notes
$40 USD in 7 days
4.5
4.5

✔ I deliver 100% work — 99.9% is not for me. ✔ Workflow Diagram Code Review ⟶⟶ Bug Identification ⟶⟶ Frontend Fixes ⟶⟶ API Debugging ⟶⟶ Data Mapping Correction ⟶⟶ Auth/Connectivity Fix ⟶⟶ Testing ⟶⟶ Production-Ready Delivery Key Highlights ✔ Rapid debugging — immediate start, 24-hour turnaround. ✔ Frontend fixes — layout, responsiveness, component errors resolved. ✔ API integration — failed requests, endpoints, and data sync fixed. ✔ Auth handling — token/session issues corrected securely. ✔ Clean code — minimal changes, maximum stability. ✔ Real-time testing — ensure smooth frontend-backend communication. ✔ No regressions — existing features remain intact. ✔ Production-ready — stable build ready for deployment. Best Regards, Asad Full Stack Developer | Debugging Expert | API Integration Specialist
$30 USD in 1 day
4.0
4.0

Hello, I have experience with React for the frontend and Node.js for the backend, having implemented features like dynamic form validations and RESTful API integrations in e-commerce platforms and booking systems. For your project, I can quickly address layout inconsistencies, enhance responsiveness, and fix API connectivity issues, ensuring smooth data flow across components. For example, I can resolve failed requests by analyzing error logs and optimizing data mapping strategies. Let's discuss!
$30 USD in 1 day
4.0
4.0

Hi there, I am a Full Stack Software Engineer with over 7 years of experience specializing in rapid troubleshooting and system stabilization. I am ready to start immediately to meet your 1-day deadline with clean, production-ready fixes. My Technical Approach: • Frontend UI: I will resolve layout, responsiveness, and component errors using Vue.js or React to ensure a polished, mobile-ready interface. • API & Backend: I will fix failed requests, data mapping, and authentication issues in your Node.js or C# backend. • Reliable Connectivity: I specialize in ensuring smooth communication between systems, utilizing tools like DataGrip and Postman for precise debugging. Why Me: I prioritize precision and deliver modular, well-documented code even under tight constraints. My background in managing complex, high-scale data systems, including a 12-million record database, ensures I can diagnose and resolve your issues without logic drift.
$30 USD in 1 day
4.1
4.1

Hello, I checked your project "Urgent UI & API Bug Fix Needed (1 Day Delivery)" and I already have a clear idea how to deliver this efficiently. I have solid experience in PHP, JavaScript, Mobile App Development, MySQL, Full Stack Development, Backend Development, Frontend Development, API Development, and I’ve worked on similar projects where I delivered high-quality, scalable, and clean solutions. Why choose me? • Strong expertise in PHP, JavaScript, Mobile App Development, MySQL, Full Stack Development, Backend Development, Frontend Development, API Development • Clean, optimized, and scalable code • Fast communication and daily updates • 100% focus on delivering results, not just code If needed, I can also suggest improvements to make your project even better. Let’s connect I’m ready to start right away. Best regards, Umer
$40 USD in 1 day
3.7
3.7

API integration bugs usually come down to mismatched response formats or auth headers not passing through correctly. I'd start by checking your network logs and backend endpoints to see where the handshake is breaking, then trace it back through your frontend data mapping. I've done similar work on a full-stack invoicing platform with 17 API endpoints and auth layers, plus handled a 24-hour VPS build that needed immediate production fixes. You can see that stuff at ffulb.com. If you can share server access and your codebase I can take a quick look at what's breaking and get it sorted. Available now.
$34 USD in 5 days
3.8
3.8

Hello! I understand you need urgent UI and API bug fixes with a 1-day delivery. I’m ready to start immediately and deliver production-ready fixes that ensure smooth frontend-backend communication. Solution: - Immediate bug triage on UI: layout, responsiveness, and component fixes with clean, maintainable code - API fixes: resolve failed requests, ensure correct data mapping, fix auth/connectivity issues, and implement robust error handling - Frontend-Backend sync: verify API contracts, error codes, loading states, and end-to-end data flow - Lightweight tests: quick sanity checks and small automated checks to prevent regressions Deliverables: - Fixed UI layout/responsiveness across target devices - Repaired API endpoints with verified data mapping and auth flow - Updated frontend/API integration points with contract alignment - Brief test scripts and notes for quick future changes - Production-ready commit history and documentation Budget + Timeline: - Fixed price: 50 USD - Delivery: 1 day (today) with progress checkpoints and a quick handover Portfolio: You can review my work on the Freelancer profile here for similar full-stack UX/UI and integration projects: https://www.freelancer.com/u/zarminagull189 Best regards,
$190 USD in 3 days
3.2
3.2

Brodivskyi, Ukraine
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