Hire the Best Payment Processing Specialists
in Ukraine

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

I help businesses automate sales, appointment booking, customer support, and internal operations using n8n, AI agents, APIs, CRM systems, and workflow automation. I build reliable systems that capture inquiries, qualify leads, book appointments, update CRM records, process documents, support customers, and reduce repetitive admin work. If your team is manually moving data between tools, following up with leads, answering the same questions, updating CRM records, or processing forms and documents - I can turn that process into a structured automation workflow. Core services: - AI Sales Automation Lead qualification, automated follow-up, pipeline updates, lead routing, task creation, CRM automation, and sales notifications. - AI Appointment Booking & Client Intake Booking flows for website forms, WhatsApp, Telegram, email, and sales teams. Includes calendar integrations, reminders, confirmations, rescheduling, no-show follow-up, and CRM updates. - AI Customer Support & Knowledge Base AI support assistants that answer customer questions using FAQs, documents, policies, product information, and internal knowledge. Includes ticket routing, escalation, CRM updates, and human handoff. - AI Operations Automation CRM workflows, onboarding, task routing, internal notifications, reporting, approvals, recurring processes, and data synchronization between business tools. - AI Document Processing Automation for PDFs, forms, invoices, contracts, emails, and uploaded files. Includes data extraction, classification, validation, summarization, routing, and database updates. - Retention & Re-Engagement Automation Follow-up systems for inactive leads, past customers, missed appointments, abandoned inquiries, reviews, referrals, renewals, and win-back campaigns. - Content-to-Sales Automation AI workflows that turn offers, product information, customer data, or business updates into outreach messages, follow-ups, sales content, and campaign-ready assets. - Lead Generation & Data Enrichment Lead sourcing, web scraping, business email extraction, list cleaning, enrichment, deduplication, segmentation, and CRM routing. Tools I work with: n8n, APIs, webhooks, Supabase, Airtable, Google Sheets, CRM platforms, Telegram, WhatsApp, email tools, calendars, databases, scraping tools, and AI models. I build workflows with production reliability in mind: * Error handling and retry logic * Duplicate prevention and validation * Alerts, logs, and monitoring * Clean CRM and database structure * Human handoff where needed * Maintainable workflows your team can understand I am a strong fit for businesses with slow response times, missed customer inquiries, disconnected tools, manual CRM work, repetitive admin tasks, weak follow-up, or operational bottlenecks. My goal is simple: help your business respond faster, operate more efficiently, and scale without adding unnecessary manual work.

I am a senior EMV L3 certification and payment integration consultant with 10+ years of hands-on experience in POS, SoftPOS and ATM solutions. I have delivered 50+ successful Visa, Mastercard MTIP, JCB, Amex and UnionPay certifications for POS/ATM vendors, acquiring banks and processors across Europe, the Middle East and Asia. My core expertise includes: • EMV Level 3 certification (Retail & Cash) • POS, SoftPOS (CPoC / MPoC) and ATM integrations • ISO8583 transaction flows and payment debugging • Processor-side integrations (Tieto, CompassPlus, Way4, SmartVista, UPC, MADA and D8-based processors) • UL / FIME certification labs and scheme simulators I regularly work with product and engineering teams at the stages where certification, scheme compliance or complex payment issues need to be resolved efficiently. Available for contract, consulting or full-time engagements. Remote.

I'm Paul — a WooCommerce engineer and technical architect with 10+ years building the systems behind serious e-commerce businesses. I've scaled a health startup from $0 to $80M in annual revenue and maintained a WooCommerce platform doing $2M/month — not by hacking things together, but by building infrastructure that actually holds under pressure. Most of my clients aren't looking for a freelancer to knock out a task. They need someone who can look at the whole picture: the architecture, the integrations, the team, the roadmap — and make good decisions across all of it. That's the role I step into. WooCommerce is often where the conversation starts. Custom checkout flows, subscription systems, complex pricing logic, performance that doesn't fall apart under load — that's table stakes for me. But the more interesting work tends to be the layer underneath: internal tools, automation pipelines, bespoke business logic, and the kind of custom engineering that doesn't fit neatly into a plugin. What I actually work on: — WooCommerce architecture, custom plugin development, and platform builds that go well beyond off-the-shelf solutions. For high-traffic stores, that sometimes means the right call is moving critical logic — inventory, pricing, order processing — out of WordPress entirely and into dedicated NestJS microservices. WooCommerce stays as the storefront; the heavy lifting happens elsewhere. That's the kind of decision I'm here to make — Internal systems and business automation: tools your team actually uses, workflows that eliminate manual overhead, integrations that connect the dots between your stack — Performance engineering — not just PageSpeed scores, but the database queries, caching strategy, and infrastructure decisions that make a platform resilient at scale — Technical leadership: stepping in as a de facto CTO or architect, leading dev teams, reviewing code, and keeping complex projects on track — AI-powered features where they add real leverage — not as a buzzword, but built into the product where it genuinely matters My stack: PHP, JavaScript, React, Node.js, NestJS, and the full WooCommerce/WordPress ecosystem — plus whatever the problem actually calls for. I work with a small number of clients at a time. If you're building something that needs to last and you want a technical partner who's done this before at scale — let's talk.

🌍 GIS Developer Who Turns Location Data Into Systems That Cut Costs and Scale Operations | 15+ Years Most businesses sitting on location data don't have a system that actually uses it. I build the tools that change: - 🗺️ Interactive web maps and dashboards - 🧭 Route optimization tools - 🛰️ Real-time asset monitoring systems - 📊 Spatial analysis solutions for faster decision-making 💡 I don’t just write code. I focus on solving business problems by leveraging geospatial data to drive smarter decisions, reduce costs, and scale operations. 🚀 Track record: ✔ 15+ years in GIS & full-stack development ✔ 13,700+ hours worked ✔ 120+ milestones completed ✔ 90+ successful projects ✔ 55+ satisfied clients 🏆 Key achievements: ✔ Developed a Non-Emergency Medical Transportation (NEMT) platform with GIS features that helped the client win contracts and grow revenue by more than 30 times ✔ Built a GIS tool that reduced the duration of the land property development potential assessment by more than 1000 times (from days to seconds). ✔ Developed a service for automatic scheduling and routing shared rides, which increased the fleet capacity by more than 20%. These are examples of how GIS can create a measurable business impact. 🌐 Industries I serve: - 🚚 Logistics - 🚑 Healthcare & NEMT (Non-Emergency Medical Transportation) - 🏡 Real Estate & PropTech - 🌳 Environmental Monitoring & Sustainability - and beyond. 🛠️ My services - GIS consulting and discovery - Proof of concept for GIS solutions - Web GIS development - Mobile GIS development - Geospatial analysis - Object detection and recognition on satellite imagery 🤝 How I work Every project starts with understanding your business processes and goals. This allows me to design a solution that solves the actual problem. My development process is iterative and usually consists of the following stages: - Discovery: Analysis and specification of your business needs, project goals, data, and requirements; UI/UX design; high-level architecture design; cost estimation; and development planning - Implementation - Testing - Delivery After each iteration (typically 1–2 weeks), I provide a demo of completed features and incorporate your feedback. This approach reduces risks, improves transparency, and ensures we stay aligned with your goals. To improve quality, accelerate development, and reduce costs, I often involve other specialists from our team, such as a Business Analyst, a QA Engineer, a DevOps Engineer, and a Data Analyst. I also use AI tools to accelerate writing code. 🌐 Industry experience 🚚 Logistics & Healthcare Transportation ✔ Transportation request booking and management platforms ✔ Fleet management systems ✔ Route optimization ✔ Dispatch automation: Vehicle Routing Problems (VRP), Dial-a-Ride Problem (DARP) ✔ Cost optimization for Google Maps API ✔ GPS and ETA tracking ✔ Geofencing ✔ API integration with dispatch software ✔ Billing (EDI 837, 835) and payment processing 🏡 Real Estate & PropTech ✔ Integration of geospatial data from multiple sources ✔ Multi-layer map visualization (zones, cadastral data, infrastructure, etc.) ✔ Site selection and suitability analysis tools ✔ Automated geospatial reporting 🌳 Environmental Monitoring & Sustainability ✔ Map-based inventory management systems ✔ Satellite imagery processing and analysis ✔ Object recognition on aerial and satellite imagery using AI/ML ✔ Spatial analytics and decision-support tools ⚙️ Core skills ✔ GIS & Mapping: Mapbox, Leaflet, OpenLayers, Google Maps API, ArcGIS, OSM, OSRM, PostGIS ✔ Frontend: JavaScript, Vue.js, React ✔ Backend: Python, Node.js, PHP (Laravel, CodeIgniter), C# ✔ Databases: PostgreSQL, MySQL ✔ Other: AWS, Docker, API Integration, AI/ML, OpenCV, Data Scraping Other experience and skills: ✔ Development of ArcGIS (ArcMap, ArcGIS Server) extensions and tools ✔ Building GIS components that can be used in both desktop and web environments (ArcMap, ArcGIS Engine Runtime, ArcGIS Server based web applications) ✔ Implementation of fast boolean operations on large polygon sets (10+ millions) ✔ GIS Specialist ✔ Web GIS Developer ✔ Interactive Map Development ✔ GIS mapping ✔ Web mapping application developer ✔ Mapbox developer ✔ Mobile application developer ✔ Database architecture design ✔ Data analysis ✔ SaaS developer ✔ Logistics supply chain software developer ✔ Supply chain management system ✔ Transportation Management System ✔ TMS software developer ✔ Trucking logistics software developer ✔ Freight management system ✔ NEMT software developer ✔ Booking Management System ✔ Dispatch software developer 📅 Available: 09:00 - 19:00 (GMT+2) 👉 Let’s discuss your goals, challenges, or ideas and explore how geospatial technology can help your business grow.

N8N Automation Architect & Voice AI Builder with 7+ years of backend engineering and 1+ year with AI. I design and ship production-ready automation systems built around n8n and AI voice agents powered by Vapi — inbound/outbound calls, lead qualification, booking, and support that plug straight into your CRM. I specialize in building production-ready automation platforms, AI-powered workflows, and backend systems that reduce manual work, improve operations, and scale reliably. Unlike pure automation freelancers, I bring strong backend engineering experience — which means I don’t just connect tools, I build stable systems behind them. Why Clients Work With Me I combine backend development + workflow automation + AI integrations to build solutions that survive production. I work with startups, SaaS businesses, agencies, and operational teams that need: AI-powered workflow automation CRM & business process automation Payment & subscription systems SaaS backend development API integrations & webhooks AI agents / voice AI / document automation I focus on: scalability clean architecture secure integrations reliability automation that reduces real operational cost Core Expertise 🔧 AI Automation / n8n / Workflow Systems I design automation pipelines that replace manual business processes. Projects include: AI Lead Qualification & CRM Routing lead verification, enrichment, scoring, routing CRM → Slack → Email automation hubs notifications, alerts, approval flows Order & fulfillment automation Shopify / WooCommerce workflows Webhook-based integration platforms API-first automation layers Subscription & billing workflows retries, failed payments, alerts, churn prevention Internal ops automations status-based triggers, task flows, reporting 🤖 AI Agents / Voice AI / LLM Integrations I build AI-powered tools that connect directly into real workflows. Experience with: AI customer support bots FAQ assistants lead qualification bots AI email reply assistants voice AI integrations CRM-connected assistants AI document parsing workflows Tech & integrations: OpenAI API VAPI 11Labs LLM workflows retrieval-based assistants structured-output pipelines 🧱 Backend Engineering / SaaS Development My strongest technical foundation is backend systems. 7+ years working with PHP ecosystems, mainly building business/admin platforms. Experience includes: Laravel applications CodeIgniter systems multi-tenant SaaS admin panels RBAC / permissions API development auth & access control queue-based workflows file-processing services business logic engines workflow engines cron-based processing 💳 Stripe / Payments / Finance Automation Strong niche expertise in payment-heavy systems. I’ve worked on: Stripe subscription systems Webhooks & event handling failed-payment recovery dunning workflows fraud-safe checkout flows payment validation layers invoice/accounting exports DATEV-style exports recurring billing logic This is especially useful for SaaS and subscription businesses. ⚙️ Integrations & Infrastructure I build stable integrations, not fragile no-code chains. Experience with: REST APIs OAuth2 Webhooks JSON transformations CRM integrations third-party platforms Twilio-based flows Slack / Notion / Airtable Google Workspace APIs Supabase / PostgreSQL Docker-based deployments reverse proxy / SSL server setup queue scaling maintenance & reliability What I Build AI workflow automation systems SaaS backends CRM automation pipelines payment & subscription logic admin panels internal tools voice AI workflows AI-integrated customer support systems webhook orchestration layers secure file-processing pipelines lead generation & enrichment systems business process automation platforms What Clients Get ✔ Backend-first automation engineering ✔ Production-ready systems ✔ Clean architecture ✔ Scalable integrations ✔ Security-focused implementation ✔ Fast communication ✔ Long-term maintainability ✔ Strong business logic understanding ✔ Reliable post-launch support Best Fit Clients I work best with: SaaS businesses subscription platforms startups agencies CRM-heavy businesses payment-heavy products operational teams businesses replacing manual workflows with automation Technical Stack Backend: PHP, Laravel, CodeIgniter, Node.js Automation: n8n, Make, Webhooks, API orchestration AI: OpenAI API, VAPI, 11Labs, LLM integrations, AI workflows Payments: Stripe, subscriptions, invoices, retries Database: MySQL, PostgreSQL, Supabase Infra: Docker, SSL, reverse proxy, server deployments Integrations: Slack, Google Workspace, CRM systems, Twilio Keywords n8n Developer, AI Automation Engineer, Backend Engineer, Laravel Developer, Stripe Integration Expert, Workflow Automation Developer, API Integration Specialist, SaaS Backend Developer, CRM Automation, Webhook Development, AI Agent Development, VAPI Integration, OpenAI API, LLM Workflows, Subscription Billing Automation, Payment Automation, Business Process Automation