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Our production MERN application is stable but starting to feel sluggish and dated, so I want a full-cycle tune-up that touches both ends of the stack. Frontend scope React needs a sharper, faster UI. Using my Figma files as reference, refine the overall look and flow, squash the obvious bugs, and push bundle size and render speed down without breaking existing features. I expect meaningful Lighthouse gains and visibly smoother page transitions. Backend scope On the Node/Express side, new and revised APIs must slot in cleanly, queries against MongoDB need tightening, and server performance has to hold under heavier traffic. Hot paths should be profiled and refactored until response times noticeably drop. Deliverables • Updated React code with Figma-aligned UI/UX tweaks • Verified bug fixes and performance metrics before vs. after • New or refactored API endpoints with Swagger/OpenAPI notes • Optimised MongoDB queries and server benchmarks • Short hand-over document and clean Git commits All work happens in our existing GitHub repo; please branch, PR, and document as you go so review is straightforward.
Project ID: 40201849
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Hello, Thank you for sharing the details of your MERN application and for considering us for this full-cycle tune-up. We understand you need to modernize and speed up both frontend and backend without breaking existing features. Using your Figma designs, we’ll refine the React UI/UX, fix visible bugs, reduce bundle size, and improve render speed—aiming for clear Lighthouse score improvements and smoother transitions. On the backend, we’ll profile hot paths, optimize MongoDB queries, and refactor APIs to handle higher traffic with faster response times. All updates will be cleanly integrated, documented, and reviewed through your existing GitHub workflow (branch, PR, commits). You’ll get: Faster, cleaner React UI aligned with Figma Measurable performance improvements (before/after) Optimized APIs with Swagger/OpenAPI notes Improved MongoDB and server benchmarks Clear handover documentation We focus on performance, code quality, and smooth collaboration. Thanks again for the opportunity—we’d be happy to get started. Best regards, DexWolf Technologies
£90 GBP in 3 days
2.2
2.2
196 freelancers are bidding on average £152 GBP for this job

Hi there To give your MERN app a real tune-up, the most critical part is treating performance as a full-stack problem rather than isolated frontend or backend tweaks. Sluggish UX usually comes from a combination of render inefficiencies, oversized bundles, slow API paths, and unoptimized database queries working together. I’ll approach this by aligning the React UI closely with your Figma designs while reducing unnecessary re-renders, tightening component structure, and cutting bundle weight to improve Lighthouse scores and perceived speed. On the backend, I’ll profile hot paths in Node and Express, refactor APIs where needed, and optimize MongoDB queries so response times stay low under heavier traffic. I use AI-assisted tooling to speed up analysis and refactoring, while applying senior-level judgment to ensure changes are safe, readable, and measurable. I’ve handled similar production optimizations where the goal wasn’t new features, but making an existing app feel modern, fast, and reliable again. I’m comfortable working in existing repos with clean branching, PRs, and clear documentation so review stays simple. My process is straightforward. We agree on target metrics and priorities, I optimize incrementally with benchmarks at each step, and then finalize with verification, documentation, and clean commits. Once scope and performance targets are confirmed, I’ll provide an exact timeline and fixed cost so expectations are fully aligned.
£135 GBP in 7 days
6.1
6.1

Hi, I can optimize your MERN stack app from scratch to finish. I will optimize the React frontend to conform to your Figma design, resolve issues, and optimize the bundle size, speed up rendering, and enhance Lighthouse scores with smoother transitions. On the server-side, I will analyze slow points, optimize MongoDB queries, and nicely add or rewrite APIs with Swagger/OpenAPI comments, improving response times under stress. You will receive precise before-and-after comparisons, clean Git commits, pull requests in your repository, and a brief handover document. Looking forward to discussing further. Best regards, Kamran
£100 GBP in 10 days
6.6
6.6

Hello, With extensive expertise in frontend development, my team at Our Software Pty can offer your MERN app the comprehensive optimization it needs. I understand the importance of making your app appear visually appealing and operate swiftly, and I am adept at leveraging Figma designs to sharpen UIs. Further, I'm well-versed with React and its nuances, which enables me to simplify existing features for better speed and lower bundle sizes, leading to improved Lighthouse scores. On the backend, our proficiency with Node/Express and MongoDB will prove incredibly useful in improving server performance under heavy traffic. I specialize in optimizing queries against MongoDB databases for faster response times. Profiling hot paths and making necessary refactoring adjustments is a routine task for us, ensuring clean API integration and smooth user experience. Operating within your existing GitHub repo will not only facilitate better project management but also ensure transparency in my progress for your ease of review. Throughout our journey together, I will also proactively document every change made, providing you with a adastrar hand-over document for easier maintenance upon project completion. Choose me to optimize your MERN stack application and you won't be disappointed Thanks!
£150 GBP in 1 day
6.0
6.0

Hi, We’ve optimized several MERN apps, including a large-scale product that required extensive performance tuning. We understand that front-end and back-end optimizations must work in harmony to deliver a truly fast product. For your project, we’ll start with a detailed analysis of the current state, identifying key areas for improvement. We’ll then prioritize optimizations based on their potential impact on overall performance. In addition to optimizing existing features, we’ll ensure that new features are built with performance in mind from the outset. Let’s schedule a quick introductory call to discuss your project in more detail and see if I’m the right fit for your needs. I’m eager to learn more about your exciting project. Best regards, Adil
£138.88 GBP in 7 days
5.7
5.7

Hello, client With over half a decade of experience in frontend and backend development, I can offer you value that not only caters to the scope of your project but also adds value to it. Simply adhering to the wonderful standards you've already set with Figma, I have an uncanny eye for detail. I'll use this skill to deliver a React codebase that not only aligns with your UI/UX tweaks but also boosts performance substantially. And as testament to my result-oriented work ethic, I will document deliverables methodologically through clean Git commits. On the backend using Node.js and Express frameworks for API creation, I'll make sure each new or revised endpoint marries seamlessly with MongoDB queries that'll be super tight, leading to stronger server performance under even heavier traffic. To top it off, I'll profile hot paths and refactor them until response times witness a notable drop. Finally, as someone who codes with fluidity on GitHub, branching out when necessary and submitting PRs and documented updates along the way, our work together will be streamlined and iterative. Grabbing hold of the massive potential that Github provides us with, we could produce a MERN app that refutes its age slowness and stands rock-solid on its core features. My mission is to rejuvenate MERN stack so prod it enjoys to perform at its highest capability. I eagerly await all queries you may have! Thanks, Denis
£150 GBP in 5 days
5.8
5.8

Hi there, I’m Ahmed from Eastvale, California — a Senior Full-Stack Engineer with over 15 years of experience building high-quality web and mobile applications. After reviewing your job posting, I’m confident that my background and skill set make me an excellent fit for your project — Full-Stack MERN App Optimization . I’ve successfully completed similar projects in the past, so you can expect reliable communication, clean and scalable code, and results delivered on time. I’m ready to get started right away and would love the opportunity to bring your vision to life. Looking forward to working with you. Best regards, Ahmed Hassan
£150 GBP in 1 day
5.0
5.0

Hello, I’m excited about the opportunity to modernize and speed up your MERN application with a practical, full-cycle tune-up that improves both UX and real performance. I can use your Figma as the source of truth to refine the React UI, fix the obvious bugs, and reduce bundle size and render costs through profiling, code-splitting, memoization where it matters, and cleanup of expensive re-renders so Lighthouse scores and page transitions improve in a measurable way. On the backend, I’ll add or refactor the required Node/Express endpoints cleanly, document them with Swagger/OpenAPI notes, and tighten MongoDB performance by profiling hot paths, improving query patterns, indexes, and response shaping until latency drops under load. You’ll get clear before/after metrics, clean commits with PRs in your existing GitHub workflow, and a concise handover document so your team can review and continue confidently. Best regards, Juan
£135 GBP in 1 day
5.1
5.1

Having been working in the web and mobile app development domain for over a decade, I am equipped with the skills that your project demands. As a full-stack software engineer, I have extensive experience in the MERN stack including React, ExpressJs, MongoDB, and Node.js which are central to your project requirements. My knowledge of advanced optimization techniques like bundle size reduction and server performance enhancements will go a long way in refining the speed and efficiency of your application. Moreover, my proficiency with Figma aligns perfectly with your expectations of Figma-oriented UI/UX tweaks. I'm known for profusely documenting my work on GitHub, which ensures comprehensive reviewability throughout the project lifecycle—hallmarked by clean Git commits and effective documentation. My previous engagements have taught me that a product's success should not only be measured against its complexity but also by its users' experience. Lastly, my versatility lends itself to a proactive approach—I've successfully worked on projects from diverse industries which means I can adapt quickly to varying contexts. Given my solid understanding of both frontend and backend engineering nuances, you can expect optimized MongoDB queries, seamlessly integrated APIs along with a refactored codebase—a benchmark for improved Lighthouse metrics—and smooth user transitions.
£100 GBP in 7 days
5.4
5.4

Hello, I'm experienced in Full Stack Development and proficient in React, Node.js, Express JS, and MongoDB. I specialize in optimizing MERN applications for enhanced performance and user experience. I will refine the UI based on your Figma files, optimize React for speed, enhance server performance, and tighten MongoDB queries. My approach will ensure significant improvements in bundle size, render speed, and server responsiveness. Let's collaborate to achieve a high-performing MERN app. What do you think about starting this project soon?
£150 GBP in 1 day
5.1
5.1

Hello, I can perform a full-stack tune-up of your MERN application to improve both frontend speed and backend performance. Frontend: Refine UI/UX per your Figma files, fix bugs, reduce bundle size, and improve render speed—delivering noticeable Lighthouse gains and smoother page transitions. Backend: Profile and optimise Node/Express APIs, tighten MongoDB queries, and ensure the server handles higher traffic efficiently. Deliverables: Updated React code, verified bug fixes, refactored APIs with Swagger/OpenAPI notes, optimised database queries, benchmarks, and a short handover guide. All work will follow Git best practices with clear branching and PRs..
£155 GBP in 1 day
4.7
4.7

⭐️⭐️⭐️Hi, I am interested in helping you tune up your production MERN app end to end and make it feel fast and modern again. I have several years of experience improving React UX, fixing performance bottlenecks, and modernizing Node Express APIs in live products without breaking existing features. I will start by reviewing your Figma and current UI flows, then apply focused UI refinements, fix obvious bugs, and reduce bundle size and render cost with profiling guided by Lighthouse so page transitions feel smoother and score gains are measurable. On the backend I will profile hot paths, tighten MongoDB queries with indexes and better query shapes, add or refactor endpoints cleanly with Swagger OpenAPI notes, and deliver before and after metrics plus a short handover document, all through a dedicated branch, clear commits, and a PR for straightforward review.
£50 GBP in 7 days
4.7
4.7

As a senior full-stack developer with proficiency in the MERN stack along with a keen eye for enhanced user experience, your project of optimizing your full-cycle MERN app caught my attention. Combining my backend skills in Node and Express, as well as my fluency in MongoDB, I can streamline your APIs and tighten up the queries to bolster performance - ensuring your app stays flawlessly responsive under heavier traffic. On the frontend end, I am well-versed in React and have a knack for constructing sharper and faster UIs. By leveraging my Figma know-how, I am ready to refine the overall look and flow of your application to align it exactly with your design references. More importantly, I have an extensive experience in pushing down bundle size and render speed without breaking existing features which would not only boost your Lighthouse scores but would also showcase visibly smoother page transitions for your users. By hiring me, you are not just bringing aboard a full-stack developer; you are getting a reliable partner who values effective communication, timely deliveries and most importantly results that caters to your business objectives. So let's optimize your MERN app together to make it faster and more efficient!
£30 GBP in 1 day
4.9
4.9

Hi , For the Full-Stack MERN App Optimization project, I will start by analyzing and optimizing the React frontend to improve UI/UX based on your Figma designs. I will then focus on refining backend APIs, tightening MongoDB queries, and enhancing server performance. Deliverables will include updated React code, bug fixes, optimized APIs, MongoDB queries, and a comprehensive hand-over document. Let's discuss further. Regards, Sai Bhaskar
£120 GBP in 5 days
4.5
4.5

As a seasoned Full-Stack Developer with over 7 years of experience, I thrive on optimizing and streamlining web applications—your MERN project description resonates strongly with my core competencies. I’m adept in fine-tuning the User Interface beyond just cosmetic tweaks by working meticulously to minimize bundle size and maximize render speed, ensuring on-point Lighthouse gains and enhanced page-to-page transitions. On the backend, Node.js isn't just a language in my repertoire, it's one of my expertise! I understand Node/Express and MongoDB intimately. Over time, I've become quite deft in strengthening backend APIs, improving query performance and comprehensively profiling what I call 'hot paths'. Additionally, my proficiency in documenting clean Git commits will help make all your code reviews uncomplicated and straightforward on the pre-existing GitHub repository. I would like to emphasize that my skill set is specifically tailored for projects like yours. Not only am I well-acquainted with the entire MERN stack, but my experience extends beyond to cloud deployment, devops practices with AWS and other platforms. Moreover, as an engineer who has built diverse automation tools & strategies in domains such as Finance and Trading—instrumental in handling large amounts of data, volume and traffic—I am confident that I can deliver a performance optimization that meets your project expectations. Let's bring efficiency back to your app, one line of code at a time.
£150 GBP in 7 days
4.3
4.3

Hello, I hope you are doing well. I’m a full-stack developer who thrives on taking mature MERN apps and turning them into fast, reliable systems. I balance sharp frontend UX with robust backend APIs, so you get both a smooth user experience and solid server performance. On the frontend, I’ve helped teams reduce bundle size, improve Lighthouse scores, and fix UI quirks while preserving features. On the backend, I’ve refactored Express routes, tightened MongoDB queries, implemented clear OpenAPI docs, and built profiling into the deployment flow to sustain higher traffic. I can handle this end-to-end in your repo with a branch-PR workflow, delivering updated React UI aligned to your Figma designs, verified performance metrics, and clean API changes with docs. I will provide a handover doc and concise commits for review. Please feel free to contact me so we can discuss more details. I am looking forward to the chance of working together. Best regards, Billy Bryan
£150 GBP in 1 day
4.5
4.5

I am highly proficient to work on this project . I am a passionate MEAN/MERN / PHP/Full stack developer having rich experience with all the latest technologies with so many successful Tasks. I have some queries to give you accurate time and price Please ping me to get started and provide you great results. Thanks
£250 GBP in 7 days
4.7
4.7

Hi there, I'm Kristopher Kramer from McKinney, Texas. I’ve worked on similar projects before, and as a senior full-stack and AI engineer, I have the proven experience needed to deliver this successfully, so I have strong experience in Backend Development, NoSQL Couch & Mongo, Node.js, Express JS, Frontend Development, Full Stack Development, MongoDB and AngularJS. I’m available to start right away and happy to discuss the project details anytime. Looking forward to speaking with you soon. Best regards, Kristopher Kramer
£150 GBP in 1 day
4.7
4.7

As a seasoned and versatile Full-Stack Developer, I have sharpened my skills over eight years, delivering comprehensive and responsive web solutions across diverse industries. My extensive experience in MERN stacks is particularly relevant to your project's optimization needs. Not only can I enhance your React-based Frontend to align it precisely with your Figma reference, but I can also identify and resolve backend bottlenecks using Node.js effectively. In addition to my proficiency with React, Node.js, and MongoDB, my arsenal of technologies encompasses crucial tools like Laravel as well as big-picture frameworks such as PostgreSQL and cloud platforms like AWS and Google Cloud. This broad skillset enables me to discern hot paths in your system and prioritize optimization accordingly, ensuring maximum performance under heavier traffic. More than just optimizing the codebase and refining UX/UI affordably, I am familiar with the industry-standard practices of using Git for effective documentation and review. I also ensure that all changes are thoroughly tested before integration and have detailed conveyance documents ready for a smooth transition. Let's take your MERN application to new heights together!
£100 GBP in 1 day
4.1
4.1

Hello , ❤️Your satisfaction is my priority❤️ I would like to grab this opportunity and will work till you get 100% satisfied with our work. I have carefully reviewed your job posting and applied because I am confident that I can help you. I have over 10 years of experience in the Job Skills field and am highly skilled at delivering high-quality results. This shows that my capabilities are a good fit for your project. I will work diligently and dedicatedly to ensure the success of your project. Please contact us via chat for a more detailed consultation. Best Regards Roman
£140 GBP in 7 days
4.2
4.2

Warm Greetings! I understand that you’re looking for a full-stack tune-up for your MERN application to improve performance, refine UI/UX, and optimize backend efficiency. To tackle this, I would start by aligning your React frontend with the Figma designs, improving render speed, reducing bundle size, and smoothing transitions, while simultaneously profiling and refining Node/Express APIs and MongoDB queries to handle higher traffic efficiently. My approach ensures all new and revised APIs are documented in Swagger/OpenAPI and that performance improvements are measurable. I’ve received excellent feedback from clients on this platform and continue to deliver high-quality work with a strong focus on reliability and results. With years of experience building websites for global clients, I offer competitive rates without compromising on quality. I’m excited about the opportunity to collaborate and look forward to working with you! Best regards, Muamer Kaukovic
£135 GBP in 7 days
4.3
4.3

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