Hire the Best Apache Solr Developers
in Ukraine

👨‍💻 About Me I'm a seasoned Full-Stack Software Engineer with a proven track record of delivering production-ready applications that drive business growth. Over the past 6+ years, I've architected and deployed 100+ web and mobile solutions for startups and established businesses, specializing in high-performance systems that handle millions of records and thousands of concurrent users. My approach combines technical excellence with business acumen—I don't just write code, I build solutions that solve real problems, scale efficiently, and deliver measurable ROI. 🚀 Core Expertise Full-Stack Development Frontend: React.js, Next.js, React Native, TypeScript, Redux, TailwindCSS Backend: Node.js, Express.js, RESTful APIs, GraphQL Databases: PostgreSQL, MySQL, MongoDB, Apache Solr, Prisma ORM Mobile: React Native (iOS & Android), Expo, App Store & Google Play deployment Cloud & DevOps Infrastructure: AWS (EC2, S3, RDS, Lambda), Vercel, Render, Digital Ocean Performance: Database optimization, query tuning, indexing strategies for high-volume data Scaling: Built systems serving 2,000+ concurrent users with sub-second response times AI & Automation Integrations: OpenAI API, custom AI workflows, intelligent automation Tools: Zapier, n8n, custom API integrations Solutions: AI-powered features, automated content generation, smart notifications 💼 What I Deliver ✅ Enterprise-Grade Applications: Scalable architectures handling millions of records ✅ Mobile Applications: Published apps on both iOS and Android app stores ✅ API Development: Secure, documented, and performant backend systems ✅ Database Optimization: Query optimization for systems with 100M+ records ✅ Authentication Systems: OAuth, Social logins (Google, Apple), secure user management ✅ Real-Time Features: Push notifications, WebSockets, live updates ✅ Payment Integration: Stripe, PayPal, custom payment workflows ✅ Complete DevOps: CI/CD pipelines, deployment automation, monitoring 🤝 Working With Me What You Can Expect: 📱 Daily Progress Updates: Clear communication and transparency 🎯 Business-First Approach: Solutions aligned with your goals ⚡ Fast Turnaround: MVP delivery in weeks, not months 📚 Clean Code: Well-documented, maintainable, and scalable 🔧 Post-Launch Support: I'm here even after deployment 💡 Proactive Solutions: I identify potential issues before they become problems 💬 Let's Build Something Great Whether you need: A high-performance web application from scratch Mobile app for iOS and Android Backend API with complex business logic Database optimization for existing systems AI integration and automation workflows Bug fixes and performance improvements I'm ready to turn your vision into reality. Let's discuss your project. What's your biggest technical challenge right now?

I build, migrate, and support Drupal platforms: new Drupal 10 and Drupal 11 builds, migrations from legacy Drupal 7, 8, and 9, and long-term support for sites that need to stay secure after end of life. I also build headless and decoupled Drupal frontends with React or Next.js. What I usually help with: • Ongoing Drupal support and maintenance • Security and module updates, bug fixing, and performance work • New Drupal 10/11 development and custom modules • Complex business logic and Twig theming • API development and third-party integrations, including CRM, payments, and Microsoft Dynamics 365 • Drupal Commerce development and integrations • Drupal upgrade assessment and planning • Drupal 7, Drupal 8, and Drupal 9 migrations to Drupal 10/11 • Headless and decoupled Drupal with React or Next.js Legacy sites usually come with years of patches and workarounds. I find the actual cause and tell you straight whether the right move is to repair, refactor, or rebuild. Most of the time, I'd rather rebuild the logic properly than keep patching around it. Migrations are the part I enjoy most. I use Drupal's Migrate API to move content, media, users, taxonomy, configuration, and custom data while preserving the business rules behind the site. Selected work: • Migrated 1.5M+ entities from Drupal 7 to Drupal 9 for a news platform, with no data loss • Implemented the Microsoft Dynamics 365 integration for Walnut Creek Foods' Drupal Commerce site • Built the custom API and event calendar behind the March of Dimes platform I also tend to stay. Some clients have kept me involved for years after the first project. Stack: PHP, Drupal 7 to 11, Symfony, React, Next.js, TypeScript, GraphQL, JSON:API, MySQL, and Apache Solr. If you need help with an existing Drupal site, a new build, migration, upgrade, headless project, or ongoing support, send me your current Drupal version and what's going on. I'll tell you whether I can help and what I'd do next.

Hello, I'm a Java (more than 10 years)/Scala(6 years)/Python developer. and have skills in Programming: • Java ( Spring, Spring Boot, Hibernate, JSF (MyFaces, Richfaces, ADF Oracle), Struts, Jfreereport, JasperReports), J2EE, JMS, Git, Maven, Web Services, REST Services; • Scala (Play Framework, Slick, Doobie, Akka, Akka-Http, Akka-stream, Cats, Scalatra, Tapir, Apache Spark, Apache Kafka, Docker); • JavaScript (Angular, jQuery); • Python (Airflow); • Application Servers: • Tomcat, Jboss, GlassFish, Weblogic; • Databases: • Oracle, MS SQL, MySQL, PostgreSQL, MongoDB; • Administration of local networks on Linux (Fedora, Mandriva, OpenSuse, Ubuntu, Elementary OS), Solaris, and Windows-based systems; • - Cloud platforms: AWS, Google Cloud.

🚀 Senior Java Developer with 14+ Years of Experience in Scalable Software Solutions As a Java Developer I specialize in building robust, scalable, and high-performance software systems using Java, Spring Boot, and modern API architectures. 💼 My Expertise: ✅ Java ✅ Spring Boot, Spring Cloud, Spring Security ✅ Microservices Architecture ✅ REST API / OpenAPI / Swagger ✅ SAP Hybris for eCommerce ✅ Frontend with React and Angular ✅ API Development & Integration ✅ Cloud Services – AWS, Docker 🔍 What I Offer as a Java Developer Over the years, I’ve contributed to a wide variety of Java-based projects — from enterprise-level platforms to e-commerce systems — helping clients convert ideas into real, revenue-generating software. I bring not just technical expertise, but also strategic thinking to each Java or Spring Boot-based application I build. ✅ Services I Provide: 🔧 Web & Backend Development (Java, Spring Boot) 🔌 API Design & Integration 🔄 Microservices with Spring Cloud 🛒 SAP Hybris eCommerce Solutions 📊 Custom CRM systems 🌐 Data Scraping and Automation 💻 Full-stack Solutions with Java + React 🧩 Tech Stack: Backend (Java & Spring): ✔️ Java, Spring Boot, Spring Cloud, Spring MVC, Spring Security, Kafka ✔️ REST API, OpenAPI, Swagger, JSON, XML ✔️ Hibernate, JPA, Quartz, Lombok ✔️ Java Concurrency, Servlet, JUnit, Mockito Frontend: ✔️ React, Angular, JavaScript, TypeScript ✔️ TailwindCSS, Bootstrap, HTML, CSS, LESS DevOps & Tools: ✔️ Git, GitHub, GitLab ✔️ Docker, Maven, Gradle, Tomcat ✔️ Postman, SoapUI, AWS (S3, EC2) ✔️ MySQL, MongoDB ✔️ IntelliJ, VS Code, JIRA, Confluence 🤝 Why Work With Me? 🗣️ Transparent communication & detailed Java-based estimates 📈 Focus on maintainable, high-quality Spring Boot code 🧠 Deep understanding of Java API integrations and real-world use cases 🕹️ Able to work independently or as part of a distributed team If you’re looking for a reliable Java Developer who knows how to turn requirements into rock-solid Spring Boot applications — I’d be happy to help. Let’s connect and build something great with Java. 🚀

Hi, I'm Oleksiy. I am a senior engineer with 9 years of experience. I like to write clean code, and although I have a lot of experience, I spend time every day learning new languages, frameworks, optimizing workflows, and so on. One of my biggest strengths is solving problems. My task is to realize YOUR ideas and create an amazing product. I specialize in architecting high-scale e-commerce ecosystems and complex microservices. With a focus on the TALL stack and AWS, I transform business requirements into scalable, production-ready web applications. Technical expertise: Core Frameworks: ✔️ PHP 8.x, Certified Laravel Expert; ✔️ TALL Stack (Tailwind, Alpine, Livewire); ✔️ Filament PHP (Admin & Panels). AI & Intelligent Systems: ✔️ LLM Integration (OpenAI, Claude, OpenRouter); ✔️ Vector Databases; ✔️ AI-driven automation. Cloud Architecture (AWS & GCP): ✔️ AWS: EC2, Fargate, Serverless (Lambda), SQS/SNS, EventBridge, S3; ✔️ GCP: Cloud Run, BigQuery, Load Balancing. Database & High-Performance Search: ✔️ SQL/NoSQL: PostgreSQL, MySQL, MariaDB, MongoDB, SingleStore; ✔️ Caching & Discovery: Redis (Pub/Sub), ElasticSearch, Memcache. DevOps & Infrastructure: ✔️ Docker (Expert); ✔️ Laravel Forge/Vapor/Envoyer; ✔️ CI/CD (GitHub Actions, Jenkins). Core Competencies: ✔️ AI Orchestration & LLM Integration. Engineering intelligent systems using OpenAI (GPT-4o), Claude, and AWS SageMaker for automated content generation, sentiment analysis, and conversational AI (Telegram/Slack/Discord). ✔️ High-Scale Cloud Architecture. Designing and deploying resilient, serverless infrastructures on AWS Fargate and Google Cloud Run. Expert in auto-scaling, load balancing, and handling high-traffic surges for rapidly growing startups. ✔️ Enterprise E-Commerce & FinTech. - Payment Systems: Seamless integration of Stripe, PayPal, Braintree, and specialized providers like LiqPay. - ERP/CRM Sync: Deep-level integration with HubSpot, E-Conomic, and Uniconta. ✔️ Advanced Microservices & Backend Engineering. Architecting distributed systems and microservices using Laravel. Expert in background data processing via complex queue management (SQS/Redis) and scheduled task orchestration. ✔️ Full-Cycle Platform Development End-to-end engineering of bespoke CRMs, multi-vendor marketplaces, and high-performance SaaS applications using the TALL Stack and Filament PHP. Feel free to contact me about projects of any complexity. I guarantee that the work will be done efficiently and on 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