Hire the Best PayPal API Developers in Kyiv, UA

Payment bugs and failed webhooks cost you real revenue. I build and fix payment flows that reconcile to the cent: Stripe integrations, subscriptions and billing, invoicing, card processing, bank APIs. 10+ years of backend engineering (Node.js, TypeScript, PostgreSQL), currently a team lead at a fintech company processing millions of transactions. $100K+ earned on Upwork, 100% Job Success, including two 6-year contracts with the same clients Senior full-stack engineer with $100K+ earned on Upwork, 4,300+ hours, and a 100% Job Success Score. I ship and stabilize production web systems—from urgent Vue/Nuxt/React frontend work to Node.js APIs, PostgreSQL, payment flows, and AI integrations. I’m a strong fit when you need: • a production bug fixed without destabilizing an existing codebase • a responsive landing page or frontend implemented from Figma • a Node.js/TypeScript API or third-party integration • payment, transaction, invoicing, or fintech business logic • an n8n or OpenAI/Claude workflow engineered with retries, validation, and safe failure handling My Upwork history includes long-running full-stack products, complex frontend animation, and quick delivery on focused frontend tasks. Clients have specifically highlighted speed, reliability, and the ability to get difficult UI work right the first time. Core stack: Node.js, TypeScript, JavaScript, PostgreSQL, Vue.js, Nuxt, React, NestJS, REST APIs, Docker, payment integrations, n8n, and OpenAI/Claude APIs. Send me the current codebase, design, or production issue, and I’ll give you a direct assessment of the solution, risks, and realistic delivery time.

I help startups and growing businesses design, build, and scale 🚀 SaaS products, 🏪 marketplaces, 🛒 ecommerce platforms, 📱 mobile applications, and 💳 subscription-based businesses. With 10+ years of experience as a 💻 Full Stack Developer, 🏗️ Solution Architect, and 👨‍💼 Technical Lead, I deliver scalable products from MVP to production. My expertise covers SaaS development, marketplace platforms, subscription billing systems, payment infrastructure, API integrations, cloud-based applications, and business-critical payment flows. I don't just implement features — I help companies make technical decisions, define architecture, optimize billing processes, integrate payment systems, and launch products faster. ⚡ 🎯 Core Expertise ✅ Full Stack Development • ✅ SaaS Development • ✅ Marketplace Development • ✅ Ecommerce Development • ✅ Subscription Platforms • ✅ Subscription Billing • ✅ Payment Gateway Integration • ✅ Stripe Integration • ✅ PayPal Integration • ✅ Checkout Development • ✅ API Integration • ✅ Mobile App Development • ✅ React Development • ✅ Flutter Development • ✅ Firebase Development • ✅ Supabase Development • ✅ Technical Product Ownership • ✅ Solution Architecture 💳 Payment & Billing Expertise I specialize in building and optimizing payment systems for SaaS businesses, marketplaces, ecommerce stores, and mobile applications. 💰 Stripe Checkout • Stripe Elements • Stripe Payment Element • Stripe Billing • Stripe Subscriptions • Stripe Connect • Stripe Webhooks • Stripe Customer Portal • Stripe Payment Intents • Stripe Setup Intents • Stripe Invoicing • Stripe Tax • Stripe Payment Links • Stripe Radar • Stripe Identity • Stripe Connect Marketplace • Stripe Connect Payouts • Stripe Webhook Development • Stripe Webhook Troubleshooting • Stripe API Integration • Stripe Billing Automation • Stripe Subscription Management • Stripe Subscription Lifecycle Management • Stripe Checkout Optimization • Stripe Checkout Customization • Stripe Recurring Billing • Stripe SaaS Billing • Stripe Marketplace Payments • Stripe Vendor Payouts • Stripe Multi-Currency Payments • Stripe Upgrade & Downgrade Flows • Stripe Trial Management • Stripe Revenue Optimization • Stripe Fraud Prevention • Stripe Payment Security • Stripe Migration 💸 PayPal Integration • PayPal Checkout • PayPal API Integration • PayPal Subscriptions • PayPal Recurring Payments • PayPal Webhooks • PayPal Billing Agreements • PayPal Marketplace Payments 🔗 Payment Gateway Integration • Subscription Billing • Recurring Payments • Billing Automation • Customer Portal • Upgrade & Downgrade Flows • Trial Management • Multi-Currency Payments • Vendor Payouts • Marketplace Payments • Refund Automation • Payment Infrastructure 🚀 SaaS & Product Development I have extensive experience building SaaS platforms and subscription-based products. ☁️ SaaS MVP Development • SaaS Architecture • Multi-Tenant SaaS Applications • B2B SaaS Platforms • B2C SaaS Platforms • AI SaaS Products • SaaS Billing Systems • SaaS Payment Infrastructure • SaaS Subscription Management • SaaS Analytics & Reporting • SaaS Integrations • SaaS Scaling & Performance Optimization • SaaS Checkout Optimization • SaaS Revenue Optimization • Mobile SaaS Applications • SaaS Marketplace Platforms 🏪 Marketplace Expertise I help businesses build and scale marketplace platforms with automated payments and vendor management. 💳 Stripe Connect • Marketplace Payments • Vendor Payouts • Commission Systems • Multi-Vendor Platforms • Booking Platforms • Service Marketplaces • Product Marketplaces • Creator Platforms • Marketplace Billing Systems • Marketplace Checkout Flows • Marketplace Revenue Models 🧠 Technical Product Ownership I often work as a technical partner helping founders and business owners turn ideas into scalable products. 🏗️ Technical Product Ownership • Product Architecture Design • MVP Planning & Development • Startup Product Development • Technical Leadership • Solution Architecture • System Design • Product Roadmap Execution • Platform Scaling • Development Team Leadership • Business Requirements Analysis • Third-Party Integrations • Payment Infrastructure Design • SaaS Architecture Consulting 🛠️ Technologies Backend: PHP • Laravel • MySQL • Redis • Elasticsearch • Apache Solr Frontend: JavaScript • React • Vue.js Mobile: Flutter Backend as a Service: Firebase • Supabase Cloud & Infrastructure: AWS • S3 • CloudFront • Lambda • Docker 📈 Recent Project Experience 🚀 SaaS Billing & Subscription Platforms: Subscription Billing • Stripe Billing • Stripe Subscriptions • Checkout Optimization • Payment Gateway Integration • Recurring Billing • Subscription Lifecycle Management • Revenue Optimization 🏪 Marketplace Solutions: Stripe Connect • Marketplace Payments • Vendor Payouts • Commission Systems • Payment Infrastructure • Multi-Vendor Platforms 🛒 Ecommerce Platforms: Shopify Integrations • WooCommerce Integrations • Stripe Payments • PayPal Payments

👀𝑶𝒑𝒆𝒏 𝒎𝒚 𝒑𝒂𝒈𝒆. 𝑾𝒉𝒂𝒕 𝒅𝒐 𝒚𝒐𝒖 𝒔𝒆𝒆 𝒉𝒆𝒓𝒆? 𝑰𝒕's 𝒂 𝒄𝒐𝒏𝒄𝒆𝒏𝒕𝒓𝒂𝒕𝒊𝒐𝒏 𝒐𝒇 𝒖𝒔𝒆𝒇𝒖𝒍𝒍 𝒔𝒌𝒊𝒍𝒍𝒔, 200+ 𝒅𝒐𝒏𝒆 𝒋𝒐𝒃𝒔 𝒂𝒏𝒅 𝒂𝒎𝒂𝒛𝒊𝒏𝒈 𝒎𝒖𝒔𝒕𝒂𝒄𝒉𝒆 𝒊𝒏 𝒐𝒏𝒆 🥸! 𝑾𝒉𝒆𝒏 𝒚𝒐𝒖 𝒘𝒆𝒓𝒆 𝒂𝒔𝒌𝒊𝒏𝒈 𝒇𝒐𝒓 𝒇𝒖𝒍𝒍 𝒔𝒕𝒂𝒄𝒌 𝒅𝒆𝒗𝒆𝒍𝒐𝒑𝒆𝒓 𝒚𝒐𝒖 𝒘𝒂𝒏𝒕𝒆𝒅 𝒕𝒐 𝒉𝒂𝒗𝒆 𝒂𝒍𝒍 𝒊𝒏 𝒐𝒏𝒆? 𝑺𝒐 𝑰 𝒘𝒆𝒍𝒄𝒐𝒎𝒆 𝒚𝒐𝒖 𝒕𝒐 𝒕𝒉𝒆 𝒔𝒎𝒂𝒍𝒍 𝒄𝒉𝒂𝒕 𝒕𝒐 𝒅𝒆𝒄𝒊𝒅𝒆 𝒊𝒇 𝒘𝒆 𝒂𝒓𝒆 𝒂 𝒎𝒂𝒕𝒄𝒉! 𝑪𝒍𝒊𝒄𝒌 "𝑴𝒆𝒔𝒔𝒂𝒈𝒆" 🏆 Top Rated Plus ✅ 100% Job Success Score ⏳ 7,000+ hours tracked on Upwork 📈 Builds serving 5 - 10M monthly users 💾 Databases holding 100M+ user records I provide Full Stack Developer work that outlives the launch - a Full Stack Developer who carries the Front End Developer and Backend Developer load on the same project, no vendor handoffs. My Full Stack Developer focus is CRM, ERP, admin systems and B2B platforms - Full Stack Developer builds with RBAC, audit trails and Stripe billing. Clients come to a Full Stack Developer instead of splitting a project between a Front End Developer shop and a Backend Developer contractor, so QA and deployment stay inside one Full Stack Developer workflow. The Full Stack Developer stack is React, Next.js, Vue, PHP, Node.js, MySQL and Redis, on AWS, GCP and Heroku infrastructure sized for peak loads up to 100K users per second. Adjacent Full Stack Developer tracks: Full Stack Web Developer rebuilds, Python Full Stack Developer pairings for data work, Full Stack Developer AI on a codebase already in production, and Full Stack Developer React funnels. My Front End Developer track is where a product stops looking like an internal tool - dashboards, admin panels, multi-tenant SaaS consoles and marketing funnels, with pages rendering in under 2 seconds. A Front End Developer React build is the default in a Full Stack Developer engagement: React with Next.js, Tailwind and Redux, plus Front End Developer Next.js server rendering when SEO carries the traffic. My Front End Developer also ships Vue 3 with Pinia when a project already runs a PHP backend. Clients searching for a Front End Web Developer or a React Developer want one Front End Developer who owns component architecture, state and API contracts. Front End Developer AI work grows every quarter: streaming responses, chat surfaces and agent panels in an app that already has users. My Backend Developer work carries the load underneath - REST and GraphQL APIs, queues, background jobs, reporting and integrations. A Node.js Backend Developer service is the usual answer when real-time traffic or webhook throughput matters, and a Backend Developer Nest.js structure keeps a growing API navigable. On the PHP side the same Backend Developer covers Laravel and custom PHP with MySQL, Redis and OpenSearch. Where a client wants a JavaScript backend end to end, backend NodeJS services sit behind the same Next.js frontend, and a Python Developer joins for data work and AI. My Backend Developer also inherits legacy systems: a WordPress Developer migration out of Gutenberg into a custom platform, an API that keeps answering while it gets replaced. Clients search by role, and the same engineers field all of them - a Full Stack Developer, a Backend Developer or a Software Developer on the server side, a Front End Developer, React Developer or Vue.js Developer on the client side, and PHP Developer, CRM Developer or ERP Developer profiles. When a build needs a Mobile App Developer alongside the web product, my engineers ship the app on the same Full Stack Developer API. As COO I oversee every Full Stack Developer engagement - the discovery, matching the right Full Stack Developer engineers, the commercial side. My Front End Developer and Backend Developer engineers own the code, and they say I am full stack developer with more than 12 years of experience - my main skill is full stack development. Clients hire me for Full Stack Developer work when they need: - a Full Stack Developer who owns frontend, backend, infrastructure and deployment - a Front End Developer for a dashboard, console or funnel that has to feel fast - a Backend Developer for APIs, integrations and reporting that stay predictable under load Recent Full Stack Developer work I shipped: - Built a Full Stack Developer identity-verification SaaS on a PHP API with Node.js real-time on MySQL and Redis - 4K+ DAU, 1M+ checks through a public Developer API. - Scaled a multi-currency voting SaaS to 2M+ users across 10 countries with vote locking and Stripe payouts, $2.5M+ revenue. - Grew a B2B luxury asset marketplace with 15 engineers - React, Next.js, PostgreSQL, OpenSearch, Stripe - to 26K MAU, 75% MoM growth, 25% engagement. - Delivered a Full Stack Developer medical-center ERP with registration, cashier, doctor and lab modules for 60 staff and 500 patients a day. Need a Full Stack Developer who covers the Front End Developer and Backend Developer sides and stays long-term - let's talk.

Versatile PHP back-end developer with 20+ years of hands-on experience across web development, server administration, and DevOps. Expert in WordPress/WooCommerce, third-party API integrations (payment systems, CAPTCHA solvers, phone verification, Meta/Instagram APIs, crypto exchange APIs), high-load multi-threaded systems, SaaS products, parsers, and web security. Writes clean, documented code and navigates unfamiliar codebases quickly. Self-motivated, detail-oriented, and reliable in independent remote work. Open to long-term contracts.

PHP/Symfony backend developer. 10+ years of experience. I work with payments, APIs, and e-commerce systems. I read unfamiliar code fast, debug well, and write clean code with tests. Code reviewer for 4+ years - I catch problems before they reach production. Stack: PHP 8, Symfony, MySQL, Redis, Memcached, Python, Docker. I use AI tools daily (Claude Code, Copilot). For 6 years I was part of a payments team (~6 people) building a white-label subscription platform - 50+ sites on one codebase. As part of that team I worked on: → Payment integrations: SEPA, card processing, Apple iTunes in-app purchases → Recurring billing: retry logic, rebill scheduling, refunds → REST APIs: internal and third-party integrations → Background jobs: crons, queues, data migrations → Per-site config: payment methods, offers, cross-sells, compliance flows Available 20-40 hrs/week. Looking for long-term hourly work. Open to: backend tasks, API integrations, payment features, general PHP/Symfony work. Let's talk.

Senior PHP Laravel Developer | 10+ Years Experience with Laravel (4–10), PHP, Vue.js, API Integrations Expert in PHP & Laravel-based development: scalable, secure, and high-performing apps Laravel + PHP are my core tools for building modern web solutions – from startups to enterprise PHP Laravel – my space 🔹 Backend: Laravel (4–10), PHP (OOP), MVC, RESTful APIs, Microservices with Laravel, Laravel Nova, Laravel Forge 🔹 Frontend: Vue.js with Laravel backend, JavaScript, jQuery, Backbone.js 🔹 Databases: MySQL optimized for Laravel, PostgreSQL with Laravel Eloquent, MongoDB, ElasticSearch 🔹 Cloud & DevOps: AWS (S3, SES, EC2, RDS) for Laravel hosting, Docker, Jenkins, CI/CD for Laravel deployments 🔹 Testing & Automation: Cypress, Laravel Dusk, Postman, WebdriverIO, JMeter, Selenium 🔹 CMS & E-commerce: OctoberCMS (Laravel-based), Shopify API, Laravel-integrated Stripe/PayPal solutions From complex Laravel backend systems to custom PHP integrations, I deliver optimized, secure, and scalable solutions. Let’s build something great with Laravel – message me now! 𝐔𝐩𝐝𝐚𝐭𝐞𝐝: April 8, 2025