Budget: 27000 UAH Deadline: 60 days
📌Hello.👋
⭐️My name is Andrey.
⭐️My work experience: 12 years+
• ➡️I can show works specifically on Game Trade Marketplaces
• 🎨Portfolio: 
Freelancehunt
• ✅Work rating on Behance (over 600,000 views)
• 💼More works here: 
Dribbble
Budget: 27000 UAH Deadline: 5 days
Hello!
I have reviewed your project - GameTrade. I understand the task: to check the security of the marketplace, find possible vulnerabilities, and correctly configure the payment system.
I can help with the following tasks:
• backend audit and search for potential vulnerabilities (authorization, forms, API, uploads, etc.)
• checking protection against common attacks (XSS, SQL injection, CSRF, bypassing authorization)
• analyzing the logic of the marketplace and operations with balance / transactions
• configuring and verifying the correct operation of the payment system
• recommendations for improving the security and stability of the project.
After the initial analysis, I will be able to compile a list of identified issues and propose solutions.
I am ready to review the code, project architecture, and discuss the details of collaboration.
Budget: 25750 UAH Deadline: 5 days
I will check the backend for vulnerabilities: injections, XSS, CSRF, authentication issues, and API. I will set up the payment system, test the entire flow from order to payment confirmation. One question: which payment system is currently in place, or do we need to select one from scratch?
Budget: 27000 UAH Deadline: 15 days
Hello.
I am a NodeJS developer. I am ready to take on the task. Write to me, we will discuss.
Budget: 27000 UAH Deadline: 4 days
Hello! I am ready to complete this project and have extensive experience in developing various applications.
Budget: 26000 UAH Deadline: 5 days
Hello! My name is Katya.
I saw your task regarding the marketplace - it sounds very interesting, and it's right up my alley)
I will be able to carefully study your backend, find vulnerabilities, and properly close them.
As for the payment system - I easily set up integrations with external APIs, so we can connect everything correctly without failures.
I would be very happy to help with your project! Write to me, and we will discuss the details)
Budget: 27000 UAH Deadline: 7 days
Good day.
I have the necessary experience, I have conducted audits for various web3 blockchain projects, I am a top auditor on the hackenproof platform. I would be happy to help find all the weak points and even fix all these problems for you. I am ready for discussion - today, I can start as early as tomorrow.
Thank you.
Budget: 27000 UAH Deadline: 7 days
Good day, I am ready to complete it. Write to me in private messages and we will discuss in more detail.....
Budget: 27000 UAH Deadline: 20 days
Hello
We worked on the Game Trade project — a turnkey marketplace (frontend + backend, payments, order logic)
We have experience in auditing and refining the backend:
— finding vulnerabilities and "holes"
— fixing logic
— configuring and stabilizing payment systems
— checking callback / webhook
We can take a look at your project, find issues, and properly set up the payment system.
Budget: 27000 UAH Deadline: 20 days
Good day
My name is Dmitry, from King Kong Lab. I have reviewed your website — it is a marketplace for digital goods with a secure transaction system (escrow), where security and proper payment processing are critically important.
We can help comprehensively: not just "take a look," but actually find vulnerabilities and bring the system to a stable state.
What we will do:
- conduct a security audit (authorization, transaction logic, possible vulnerabilities)
- check the backend and business logic (logic holes, bypasses, errors)
- set up and test the payment system (correct payment processing, statuses, protection against duplicates and errors)
- check integrations and notifications
- optimize operational stability
We work until the result — so that the site operates safely and without payment issues.
We have experience working with marketplaces, payment systems, and complex logic.
I am ready to get involved, review the project, and propose a specific plan for corrections.
Budget: 27000 UAH Deadline: 20 days
Hello, I would like to work on your project, bring it to a normal state, and I will connect the payment system without any problems.
Budget: 26000 UAH Deadline: 14 days
Hello! I have analyzed your marketplace GameTrade. The site is built on Next.js and Node.js, which is a great foundation for scalability and security. I have extensive experience in developing backend logic and integrating payment systems.
My work plan for the project:
Security Audit: I will conduct a complete review of your API endpoints and authorization logic for vulnerabilities (SQLi, XSS, access logic).
Payment System: I will set up or update the payment system with a focus on automating Escrow processes. I have experience working with Stripe and other international gateways.
Compliance: I will check the correctness of transaction processing and the protection of user data.
I am ready to start the audit today and provide a detailed report on the identified vulnerabilities. I look forward to your feedback to discuss the details!
Budget: 27000 UAH Deadline: 3 days
Hello! I am ready to look at the backend, check the website for vulnerabilities, and properly set up the payment system. The exact price depends on the website engine, the complexity of the marketplace, and the chosen payment system. I can start right now.
Budget: 27000 UAH Deadline: 5 days
Hello. I am ready to join as a backend developer, conduct a security audit of the project, and bring the payments to a working and correct state.
What I will do
1. Quick audit of vulnerabilities and settings (authorization, permissions, API, validation, uploads, SQLi/XSS/CSRF, leaks, logs, rate limit)
2. Check the payment flow (invoice creation, redirects, 3DS, webhooks, signatures, idempotency, order statuses, refunds)
3. Fixes in the code and configuration to ensure payments are stable and secure
4. A short report on what was found and what was fixed
Timelines and price (short version)
- Stage 1: express audit and payment diagnostics 1 day, $60-120
- Stage 2: fixes and payment setup 2-4 days, $250-600 Total usually 3-5 days, $310-720 more precisely after access to the code and understanding of the payment provider
Clarifications to immediately assess the scope
- What is the backend (PHP Laravel, Node, Python, Ruby, other) and is there access to the repository
- What payment provider is being used and what exactly is not working now (errors, declines, webhooks not coming, incorrect statuses)
- Are only payments needed or also withdrawals, fees, anti-fraud
- Is there a test environment and test keys for the payment system
- Access to the server and logs (Sentry/CloudWatch/pm2/nginx)
I am ready to start immediately after access is provided.
Budget: 27000 UAH Deadline: 7 days
Good day, Nikita.
My name is Denis, I specialize exclusively in backend development. I know how to properly fix vulnerabilities, how to correct bugs, and how to quickly and effectively understand someone else's code. I do my work with quality and integrity. Clearly on time.
I have a couple of questions:
1) You mention vulnerabilities, so you have had such experience? What exactly happened?
2) What is the backend written in, as I see the frontend is on Next?
3) Which payment platform needs to be integrated?
Let's discuss everything in detail, okay? 🙂
Best regards, Denis
Budget: 27000 UAH Deadline: 4 days
Hello. I can connect.
I will look at the backend, find weak points in logic and security, and properly bring the payment system to a working state so that everything runs smoothly and without surprises. If the site is already live — that's even better, we can quickly go through the real bottlenecks and not guess in theory.
