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My digital product is live but the checkout flow stalls because payment processing is still missing. I want the backend updated so customers can pay with multiple forms—credit cards, PayPal and, if feasible, a crypto option. The immediate task is clean integration with a reliable payment gateway; I’m open to Stripe, PayPal, Square or another solution you can justify for our tech stack. What you’ll tackle: • Wire the chosen gateway into the existing backend, set up the necessary endpoints and webhooks, and make sure tokens and keys are stored securely. • Implement exhaustive sandbox testing, then push to production once we’ve confirmed successful transactions. • Add lightweight reporting so I can see a summary of completed, failed and pending payments from the admin panel or an API endpoint. • Deliver well-commented code, an `.[login to view URL]` for secrets, and short deployment notes so future maintenance is straightforward. Security and reliability are non-negotiable; please follow PCI guidelines, encrypt secrets, and log errors without exposing sensitive details. The sooner we can accept real payments the better, so propose a realistic timeline and any stack requirements you have and let’s get this wrapped up.
Project ID: 40328905
95 proposals
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Active 25 days ago
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95 freelancers are bidding on average $153 USD for this job

Dear Client, I am ready to help you on Immediate basis. I would love to discuss further, ASAP you schedule the interview. I am an experienced Full-Stack website developer, Develop near about 550 websites. I can create custom CRM, Laravel, ERP, Custom Plugin, Wix, WordPress, SquareSpace, Webflow, Shopify, MySQL, JavaScript, HTML, Woo-commerce Integration, jQuery, Third Party API integration, Bug Fixing, Troubleshooting, Malware Cleaning, Site Migration. When can we discuss? Regards
$150 USD in 3 days
8.2
8.2

Hi, We’ve built multiple products with complex payment flows, integrating Stripe, PayPal, and Razorpay for credit cards, wallets, and crypto payments. We also developed a custom payment gateway for one product, so we understand the nuances of securely handling sensitive data. For your project, we can use Stripe and PayPal to cover 90% of payment scenarios. We’ll implement a robust solution that allows you to add more gateways later without major refactoring. We prioritize security and reliability, ensuring PCI compliance and using encrypted secrets. We also provide a dedicated DevOps resource to manage server security and performance, so you don’t have to worry about it. Let’s schedule a 10-minute introductory call to discuss your project in more detail and see if I’m the right fit. Feel free to message me anytime—I usually respond within 10 minutes. I’m eager to learn more about your exciting project. Best regards, Adil
$125.63 USD in 7 days
7.2
7.2

As a seasoned freelancer, I bring unparalleled depth and breadth to my work in API integration, Backend Development, PayPal API and PHP. Such a hybrid of skills is precisely what your project demands. With your digital product already live, I understand the urgency to fix any payment processing flaws. My technical capability in wireframing, UI/UX design, and working with CMS platforms like WordPress makes me well-versed in e-commerce, including WooCommerce which I can leverage for the task at hand. Notably, security and reliability are paramount for your project; requirements that align excellently with my approach. I strictly adhere to PCI guidelines and am committed to encrypting secrets and safeguarding sensitive data when logging errors. I have a knack for delivering secure, efficient code that withstands rigorous testing while maintaining flexibility for easy future maintenance. To improve the checkout flow on your digital product, I propose leveraging Stripe as a feasible payment gateway solution devoid of any compromise on security or reliability. My 1000 character limit won't do justice to an overly-detailed plan but rest assured that hiring me would result in well-commented code, optimal deployment procedures and short post-implementation documentation to ensure straightforward maintenance going forward. Let's get started! Thanks, Jay
$140 USD in 7 days
6.7
6.7

Hello! I’m excited to help you resolve the payment processing issue in your digital product’s checkout flow. With over 9 years of experience in full-stack development and expertise in backend technologies such as Laravel and native PHP, Smart Sols is confident in quickly identifying and fixing the problem so your users enjoy a smooth purchase experience. We understand the urgency of having a reliable payment system live and are committed to delivering a robust, secure backend fix promptly. We would be happy to discuss your current setup and ensure the payment gateway integrates seamlessly, eliminating any stalls during checkout. Looking forward to collaborating with you and getting your product payment-ready!
$250 USD in 3 days
6.9
6.9

Hi, As per my understanding: integrate reliable payment gateway (Stripe/PayPal/crypto) into existing backend—secure endpoints/webhooks, sandbox+prod testing, admin payment reports, PCI-compliant with clean deployment docs. Implementation: - Stripe primary + PayPal SDK, crypto via CoinPayments if needed. - Secure token vaulting, webhook verification, error logging. - Admin dashboard endpoint for transaction summaries. I'll share my portfolio on your first message. Queries: Current backend stack? Preferred primary gateway? Best Regards
$350 USD in 7 days
6.9
6.9

With over a decade of experience as a WordPress developer and exposure to various frameworks like Laravel, Codeigniter and even e-commerce systems like Shopify, I’m proficient at applying my skills across projects of distinct needs. I’m also well-versed in mainstream payment gateways including Stripe, PayPal, and Square that you've mentioned in the project description. Moreover, my mastery in PHP makes me an ideal fit for the backend payment processing fix project you have at hand. In addition to what has been noted in the project responsibilities, my team will conduct exhaustive sandbox testing followed by thorough production testing before making any module live. My design skills also enable me to provide you with lightweight reporting options in a user-friendly admin panel or through API endpoints for easy summary viewing of payments' status. Considering our expertise with WordPress, we can also customize your administrative dashboard to include this feature smoothly. Since we strictly adhere to principles of quality work and prompt delivery while maintaining open channels of communication, working with us means your desired project outcomes are effectively achieved without undue distress or delays. Let’s talk details and give your customers an enhanced checkout experience without compromising security.
$199 USD in 7 days
6.3
6.3

Hi, As a individual developer, I can jump in at your suitable time. I can help with your project, focusing on integrating a secure multi-payment backend flow, webhook handling, sandbox-to-production rollout, and simple payment reporting without overcomplicating your current system. With my expertise in full-stack development and experience working with modern web technologies like Stripe, PayPal API, backend payment processing, webhook security, .env-based secret management, and admin/API reporting endpoints, i can update your existing product so it accepts real payments reliably and tracks completed, failed, and pending transactions cleanly. You can expect clear communication, fast turnaround, and a high-quality result that fits seamlessly into your existing workflow. Best regards, Juan
$140 USD in 1 day
5.9
5.9

Hello, I am backend engineer with 8 years of experience in payment integration and setup.I will get this sorted. Let’s connect
$200 USD in 3 days
5.7
5.7

As a seasoned web developer with 8 years under my belt, I have the skillset you need to get your payment processing back on track. My expertise lies in MVC frameworks such as Codeigniter and Laravel, which align with your tech stack requirements. I am also well-versed in API Integration and PHP - crucial for wiring the chosen gateway into your backend and setting up the necessary endpoints and webhooks. Rest assured, I place high priority on security and reliability; I follow PCI guidelines, encrypt secrets, and take caution to log errors without exposing sensitive data. Being an all-round web professional, my familiarity with different open source applications adds great value to your project. Additionally, my experience in handling digital marketing components like SEO, camping, and social media marketing can be an asset when it comes to expanding your payment options to include cryptocurrencies. Bottom-line, my track record in building and maintaining web based solutions coupled with a deep understanding of effective digital marketing brings together the perfect blend of skills for this project. With my meticulous attention to detail and fluctless implementation, we'll see successful transactions in no time. Let's do this!
$80 USD in 1 day
5.2
5.2

Hello there, I will wire Stripe as the primary gateway — handling endpoints, webhooks, and token storage — then add PayPal as a secondary method and evaluate a crypto option via Coinbase Commerce or similar. One thing I will configure early: idempotency keys on every charge request. This prevents duplicate charges if a webhook retries or a customer double-clicks, saving you refund headaches before they start. Questions: 1) What is your current backend stack — Node, Python, or something else? 2) Do you have a Stripe or PayPal merchant account already set up? Looking forward to your response. Best regards, Faizan
$90 USD in 5 days
5.5
5.5

Hi there, It's clear that you need to get your checkout flow working smoothly by integrating a reliable payment gateway for multiple payment options. With 4+ years of experience in backend development, I can help wire the chosen gateway—be it Stripe, PayPal, or another option that fits your tech stack—into your existing system. I’ll ensure that all necessary endpoints and webhooks are set up securely, following PCI guidelines to protect sensitive information. I’ll also implement thorough sandbox testing to confirm everything works before going live. Plus, I’ll create a lightweight reporting feature for tracking payments right from your admin panel. One question I have is: do you have a preference for any specific payment gateway based on your user base, or are you open to recommendations based on what would work best? Best regards, Arslan Shahid
$30 USD in 3 days
5.0
5.0

Hi, As per my understanding: Your product is live but checkout is incomplete due to missing payment processing. You need a secure backend integration supporting multiple methods (cards, PayPal, possibly crypto), with proper testing, webhooks, and basic reporting. Implementation approach: I’ll integrate a reliable gateway (Stripe + PayPal for coverage, optional crypto like Coinbase Commerce if needed) into your backend. This includes secure API setup, webhook handling for payment states, and safe key management via env configs. I’ll implement end-to-end sandbox testing, then deploy to production after validation. A lightweight reporting layer (API/admin view) will track completed, failed, and pending transactions. Code will follow security best practices (PCI compliance, encrypted secrets, safe logging) with clear documentation for future maintenance. A few quick questions: 1. What is your current backend stack? 2. Do you already have merchant accounts (Stripe/PayPal)? 3. Is crypto mandatory or optional for phase 1? 4. Do you need subscription support or one-time payments only?
$98 USD in 5 days
5.4
5.4

As a seasoned developer with a decade of experience in handling complex backend systems, I understand the criticality of ensuring a smooth and secure payment flow for your digital product. My extensive exposure to various frameworks, such as Laravel and React, coupled with my expertise in API Integration and PHP, makes me well-equipped to handle the task at hand. I've previously worked on integrating multiple payment gateways using Stripe, PayPal, and Square - which specifically aligns with your project requirements. Not only do I bring strong technical acumen but also a keen appreciation for usability—essential while creating the lightweight reporting system you need. Whether it's delivering snippets of code that are easy to decipher or crafting deployment notes that simplify future maintenance, rest assured -- I will be there to support you even post-launch. Let's work together to streamline your backend payment processing and take your digital product to new heights!
$100 USD in 1 day
4.6
4.6

Hi there, I specialize in integrating payment gateways into custom PHP applications, including Laravel and CodeIgniter frameworks. ✔️ ️ Secure and seamless integration (one-time payments, subscriptions, refunds, webhooks) ✔️ ️ Clean error handling, sandbox/live setup, and API key protection ✔️ ️ Tested workflows with clear documentation if needed I can start right away and ensure your payment system works reliably across all platforms. Let’s connect to finalize your gateway preference and project requirements. Thanks and regards, Prakash
$250 USD in 7 days
4.8
4.8

Hi, I am a full-stack backend developer with 8 years of rich experience with a background in Node.js, PHP, Stripe, PayPal API, and payment processing. For this project, the most important part is fixing the checkout flow with secure and reliable payment handling across multiple methods. I can integrate Stripe and PayPal with proper webhooks, secure key management, sandbox testing, and add a simple reporting layer while keeping everything aligned with PCI practices. I'm an individual freelancer and can work on any time zone you want. Please contact me with the best time for you to have a quick chat. Looking forward to discussing more details. Thanks. Emile.
$250 USD in 7 days
4.6
4.6

Hey there Hope the weather nice in United States I am interested working on your project Backend Payment Processing Fix I’ve reviewed your CRM project requirements and it aligns well with my experience in building structured, scalable systems. I understand that a CRM isn’t just about features it needs to be reliable, user-friendly, and optimized for real workflow efficiency. Let us speak over the chat and discuss the details of the project. I deliver high-quality work that aligns perfectly with your goals and stays within budget. Best Regards, Hussain
$100 USD in 7 days
4.3
4.3

Hi There, I understand that you need to enhance your backend to incorporate a smooth payment processing system for your digital product. I specialize in developing secure and efficient payment gateways, ensuring customers can pay via credit cards, PayPal, and potentially cryptocurrency. With over 7 years of experience in PHP, Software Architecture, and API Integration, I can effectively wire a payment gateway into your existing setup. I prioritize security and reliability, following PCI guidelines while ensuring that sensitive details are always encrypted and well-protected. Your project requirements match my skill set perfectly, and I'm ready to implement sandbox testing and provide you with transparent reporting for transactions. You can review my portfolio here: https://www.freelancer.com/u/KanzahAfaqAhmad I’m keen to discuss your project further and provide a realistic timeline for completion. Thank you for considering my proposal. Regards, Kanzah Afaq
$250 USD in 7 days
4.3
4.3

I can quickly implement and stabilize the missing payment processing logic so your digital product’s checkout flow completes smoothly. I understand how critical it is for you to start collecting revenue without disrupting the existing live experience. I’ve worked on similar backend payment integrations, including Stripe and other major gateways, resolving stalled checkouts, handling webhooks, and ensuring accurate order and access provisioning after payment success. My focus is always reliability, security, and clear error handling. My approach would be to review your current backend, identify where the payment step is breaking, integrate or finalize the gateway, test end-to-end with real and test transactions, and add logging so future issues are easy to diagnose. I would love to chat more about your project! Regards
$140 USD in 7 days
4.7
4.7

Hi, I'm a Full Stack Developer specializing in backend systems, API integrations, and workflow automation using tools like n8n. I have experience building and debugging e-commerce checkout flows and payment processing integrations. Given your project description, I can analyze your current setup, identify the bottleneck in the payment process, and implement a robust fix to ensure smooth transactions. I'm comfortable with debugging, performance optimization, and ensuring a reliable and secure payment processing experience for your customers. I can also set up monitoring and alerting to proactively catch any future issues. Looking forward to your reply. Thanks and regards, Vinod Malviya
$180 USD in 3 days
4.2
4.2

Hi, What payment gateway are you currently using, and can you share the tech stack details? I can help you integrate a reliable solution like Stripe or PayPal into your backend so that your customers can pay seamlessly with multiple options. I will ensure secure integration by setting up the necessary endpoints and webhooks while adhering to PCI guidelines. I’ll conduct thorough sandbox testing to confirm successful transactions before going live. Lightweight reporting for completed, failed, and pending payments will be included, along with well-commented code and concise deployment notes for easy maintenance. With 5+ years of experience in payment integrations and a solid understanding of security best practices, I’m confident we can get this task wrapped up quickly. Let’s discuss the timeline and any requirements you have! Best Regards, Mahad Sheikh
$30 USD in 2 days
4.2
4.2

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