Hire the Best Senior Software Engineers

I am a Senior Fullstack Developer with over 15 years of hands-on experience in building and scaling Java , C# / Net , Angular applications for startups, enterprises, and SaaS platforms. Currently, I’m working as the Chief Technology Officer at InventorSoft, a software development agency specializing in web and mobile solutions. I bring a strategic mix of technical depth, team leadership, and product vision to every project. Why hire me🧐: 📌 Expert in Scalable Java and .Net Architectures - Over 15 years of experience in developing Java, .Net, C#, Angular scalable applications from different domains. - Backend systems built with Spring Boot (15+ years) – Delivered scalable microservices and high-performance business logic for enterprise-grade applications. - ORM & data access with Hibernate – Applied advanced ORM techniques for efficient database interactions, query optimization, and data integrity in distributed systems. - Frontend development with Angular & Thymeleaf Designed and delivered 200+ robust backend systems for SaaS products, e-commerce platforms, and enterprise clients. 📌 Cloud-Native Platform Engineering Specializes in building secure, scalable, cloud-native platforms using leading cloud providers: - 8+ years of production experience with AWS – Deployed scalable, secure, and high-availability applications. - 9+ years of hands-on Azure expertise – Delivered enterprise-grade solutions with Azure App Services, Azure DevOps, and SQL/Azure Storage. - 5+ years of experience on Google Cloud Platform (GCP) – Built and deployed containerized microservices using GKE, Cloud Run, and Firebase. 📌 API-First & Cloud-Native System Design - Strong background in API integration and microservice architecture. - Created high-performance APIs for platforms serving 50K+ users, ensuring seamless third-party integration and scalability. - Experienced in Docker & Kubernetes, enabling CI/CD pipelines and resilient containerized systems. 📌 Full-Stack Leadership & Agile Team Management - Led and mentored teams of 5–25 developers through all stages of the SDLC—requirements gathering to deployment and maintenance. - Specialized in building cross-functional teams for backend-heavy systems, modern UIs (React, Angular, Thymeleaf), and DevOps automation. My latest achievement as a Software Architect: 🤝 Partnered with 45+ SaaS companies to design and deliver secure, scalable platforms using Spring Boot, AWS, and modern cloud services. 🚀 Helped 10 tech startups scale from MVP to production—selecting the right tech stack, defining cloud-native architecture, and assembling strong dev teams. 💼 Enabled 5 client acquisitions through the development of enterprise-grade software that attracted major buyers and investors. 🏭 Led a digital transformation project for a multi-billion-dollar oil company, delivering a secure, API-first platform that automated mission-critical operations. 🧩 Technologies I Specialize In - Languages/Frameworks: Java, C#, .Net, Spring Boot, Hibernate, Thymeleaf, .Net Core - Cloud Platforms: AWS (8+ years), Azure (9+ years), Google Cloud (5+ years) - DevOps Tools: Docker (7+ years), Kubernetes (5+ years) - Integration & Architecture: RESTful API integration, microservices, clean architecture, CI/CD pipelines Clients that I am proud of: 💻 Shoeby – A fashion retail platform focused on modernizing the e-commerce experience with intuitive UI, product personalization, and seamless shopping journeys. 💻 CellRebel – Provides advanced mobile network analytics, helping telecom companies improve coverage and performance based on real user data. 💻 Blade – A technology-powered aviation company offering urban air mobility services, including helicopter and seaplane flights. 💻 Matics – A real-time operational intelligence system for manufacturers, offering production insights and process optimization across the factory. 💻 MedischeScholing – A medical e-learning platform that enables healthcare professionals to access, register for, and track accredited training and certifications. ➡️ Learn more about other projects on the InventorSoft portfolio Keywords: Java, Backend, Developer, Fullstack, Web, Cross-Platform, Mobile, Application, AI, OpenAI, Service, App, Development, Engineer, Integration, Build, Website, Expert, Spring boot, MySQL, Development Team, Integrated, SaaS Platform, remote, Full-stack, Senior, Software, Client Management, GraphQL, API, .NET, Asp.net, Programmer, Technical Lead, Dashboard, MVC, Developers, ASP.NET, AspNetZero, core, software, MAUI, C#, Angular, .Net, Core, Principal, Performance, Scalability, Microsoft, Blazor, SQL, Server, Frontend, React, Ruby on Rails, RoR/React, front-end, Tailwind, feature, ROR, TailwindCSS, Technical Staff, JavaScript

You need software that solves a real problem, built right the first time, by people who understand your business and not just your stack. I'm Orest, founder of SoftDoes. We're a U.S.-based custom software firm working with: • Non-technical founders with a vision • Technical leaders who need help but not additional headcount • Business operators solving operational complexity Our team has delivered across healthcare, fintech, construction, legal, real estate, and regulated industries where compliance-readiness is required and getting it wrong isn't an option. Our clients tend to show up in one of three situations: they have a product vision and need someone to build it, they have internal engineering that's stretched too thin, or they have operational complexity that off-the-shelf software simply can't fix. We've handled all three. What we deliver: • Custom software and SaaS platforms built for scale • AI implementation and automation built into real workflows • Web and mobile applications • Cloud infrastructure on AWS, GCP, and Azure • Full-stack development across React, Next.js, Node.js, and Python What clients tell us, consistently: we listened, we delivered what we said we would, and they didn't have to babysit us to get there. A healthcare founder went from concept to a live, compliant product in under six weeks. A construction company replaced five fragmented tools with one custom operations platform. A fintech team cut onboarding time in half with an AI-assisted workflow we built in a single sprint. We work best with companies that are big enough to need real software and clear-eyed enough to know that building it wrong the first time costs more than doing it right. If that's where you are, let's talk. 🇺🇸 U.S.-based. U.S.-led. Kansas City, MO. Services: Custom software development SaaS development Enterprise software Web application development Mobile app development Full-stack development Product development / MVP build Platform modernization / rebuild Systems integration Workflow automation Business process automation API development / API integration Backend development Frontend development AI development AI integration AI automation LLM integration RAG (Retrieval-Augmented Generation) AI chatbot development Document AI AI-powered workflows Prompt engineering AI agents Data extraction automation React Next.js Node.js Python TypeScript JavaScript REST APIs GraphQL PostgreSQL AWS Google Cloud (GCP) Microsoft Azure Vercel Docker Terraform CI/CD Cloud / DevOps keywords Cloud architecture Infrastructure as code DevOps Deployment automation Scalability / performance optimization Reliability engineering Monitoring / observability HIPAA compliance / healthcare software PCI / fintech software SOC 2 readiness (if applicable) Security best practices Compliance-ready systems Audit-friendly systems Role-based access control (RBAC) Operations platform Internal tools CRM/ERP custom build Data pipelines Dashboards & reporting Process digitization Tool consolidation Onboarding automation

$100M+ in Client Revenue | Expert-Vetted (Top 1% Upwork) | 240+ Projects | 100% Job Success | 10+ Years on Upwork I’m a Full Stack Developer, SaaS Developer and Backend Developer focused on building production-ready software that holds up under real-world usage. My work sits at the intersection of software developer, web developer, and SaaS platform builder, with a strong backend-first mindset and deep attention to scalability, performance, and long-term maintainability. As a Full Stack Developer, I take ownership of systems end-to-end, pairing robust backend architecture with clean, modern interfaces. My frontend work is typically React-based and I often collaborate with or replace traditional React developer or web developer setups by owning both frontend and backend in a single, coherent system. While I’ve previously worked as a WordPress developer and integrated WordPress-based sites into custom platforms, my current focus is on custom SaaS and API-driven systems rather than CMS-centric builds. As a SaaS Developer, I help companies design, build and scale SaaS products, internal tools and API-driven web applications intended for long-term use. My experience as both a Backend Developer and software developer allows me to think beyond features and focus on architecture, reliability and operational stability from day one. Many of the platforms I build support internal teams, customer dashboards and multi-role workflows where permissions, data integrity and business rules are critical. In my day-to-day work as a Backend Developer, I design and implement backend services, APIs and data models that power SaaS platforms, complex web applications and mobile-connected systems. I regularly work with Node.js and Python, drawing on my background as a Python developer to build scalable services, background jobs and asynchronous workflows that perform reliably in production. As a Full Stack Developer, I ensure these backend systems integrate cleanly with frontend applications, mobile extensions and third-party APIs. When required, I support frontend and mobile app developer workflows using React and React Native. This end-to-end ownership is a key reason clients bring me in as a Full Stack Developer rather than splitting work across multiple roles. A significant portion of my work as a SaaS Developer and Backend Developer involves building internal platforms, dashboards and API-first systems that integrate external services. In these projects, I often collaborate closely with product, growth, or analytics teams, including teams focused on SaaS marketing by designing clean data pipelines, event tracking and backend logic that supports experimentation, reporting and lifecycle insights. When projects require AI-powered functionality, I bring hands-on experience integrating AI into backend systems. While my primary role remains Full Stack Developer and Backend Developer, I regularly implement AI-enabled workflows, data processing pipelines and LLM-driven features inside SaaS platforms. This allows me, as a SaaS Developer, to deliver AI functionality that is reliable, observable and cost-controlled rather than experimental. Clients typically work with me when they need: - a Full Stack Developer who can own frontend and backend - a SaaS Developer who understands long-term scalability constraints - a Backend Developer experienced with real production systems - mobile app developer and React developer experience as a software developer - backend services built with Node.js or Python by an experienced Python developer - web applications with complex workflows and business rules from a senior web developer - API-driven architectures and third-party integrations - SaaS platforms designed to support growth, analytics and SaaS marketing data needs - MVPs that can realistically evolve into long-term SaaS products A large part of my work as a Full Stack Developer, SaaS Developer and Backend Developer focuses on: - multi-role dashboards and internal tools - authentication, authorization and permissions - API-first backend system design - integrations with external platforms, including legacy CMS or WordPress-based systems when required My core work as a Backend Developer and Full Stack Developer covers: - backend services built with Node.js and Python - APIs, background jobs and integrations - databases such as PostgreSQL - modern stacks using tools like Supabase - AI-enabled backend features where they add real business value I regularly work on MVP builds and early-stage products as a SaaS Developer, with strong focus on solid backend foundations, sensible scaling paths and avoiding short-lived prototypes. Based on scope and timing, I work hands-on as a Full Stack Developer, SaaS Developer and Backend Developer and when useful, involve specialists from my team. Long-term results come from clarity and intentional system design. I focus on delivering software that teams can confidently run, maintain and scale.

$53M+ Raised by Clients | 84+ Products Delivered | 100% Job Success | 14 Years in SaaS ✅ 14 years as a Full Stack Developer, now CTO & Founder of Gearheart, an Enterprise SaaS product development studio ✅ Co-Founder & CTO at Beyond the Wow, an AI-native MVP studio ✅ As a SaaS Developer, I've helped 84+ startups and growth-stage SaaS teams scale their products ✅ Built SmartSuite from scratch as lead Full Stack Developer - $38M raised, 7M+ users ✅ 2-4x faster delivery as a SaaS Developer using Claude Code, Lovable, Cursor, and Replit ✅ Top Developer at Clutch and Goodfirms I'm a CTO and SaaS Developer specialist with 20 years experience as a Full Stack Developer for SaaS companies, working as a React Developer on the frontend when the project calls for it. Most founders fail building wrong things. As a SaaS Developer and MVP Developer focused on SaaS architecture and rapid deployment, I personally deliver on 84+ products for 70+ SaaS clients across 7 countries. Depending on the project I work as a React Developer, WordPress Developer, or Mobile App Developer. I bring SaaS Developer speed with Full Stack Developer depth and Software Developer expertise into every project. 🌟 ENGINEERING STANDARD - SAAS DEVELOPER EXCELLENCE My SaaS Developer standard comes from 14 years working as a SaaS Developer, delivering results like: - SmartSuite - a SaaS Developer MVP I built from startup concept as React Developer and Full Stack Developer SaaS specialist: $1.2M ARR in 4 weeks, $38M raised, Capital One trusted - Globalli - a SaaS Developer build for enterprise: HR/payroll across 125+ countries, SOC2 Type II, $15M raised, delivered as a SaaS Developer specialist including NextJS Developer and WordPress Developer work, all as a Full Stack Developer SaaS architect 🔧 WHAT I CAN HELP YOU WITH - SAAS DEVELOPER & MVP DEVELOPER SERVICES - Discovery & Prototype: a SaaS Developer engagement that gets you a clickable prototype in 5 days - NextJS Developer ready and prepared for startup scaling - Rescue Diagnosis: a SaaS Developer review with Full Stack Developer optimization and a performance audit included - MVP & Landing Page: SaaS Developer MVP Development in 3 weeks, handling both the React Developer frontend and the Software Developer backend myself - Sprint Subscription: a long-term SaaS Developer partner, bringing Mobile App Developer and WordPress Developer support as needed ⚡ MVP SPEED - SAAS DEVELOPER & MVP DEVELOPER DELIVERY - Legal SaaS platform + AI, delivered as a SaaS Developer → 2 months - AI Receptionist with CRM, an MVP Developer Python build → shipped in weeks - B2B Dental SaaS - SaaS Developer and Web Developer NextJS delivery → 3 weeks - Medical device MVP - MVP Developer Full Stack development with Software Developer patterns → 2 weeks - Multiple SaaS Marketing web projects built with Web Developer craft, React Developer expertise, and SaaS Developer focus 💡 WHY WORK WITH ME - Product Thinking First: as a SaaS Developer I ask "should you build?" not "what to build?" - most Software Developer freelancers skip this critical step, I don't - AI Speed & Quality: as a Full Stack Developer I use Claude Code, Lovable, Cursor as an engineer - not a prompt writer. Delivers enterprise-grade solutions - I'm a Founder Too: Full Stack Developer founder mentality, deep SaaS Marketing understanding, real startup experience - Offshore + Enterprise Standard: Ukraine-based Full Stack Developer with NextJS Developer, WordPress Developer, and Mobile App Developer expertise, plus Python Full Stack Developer capability. I deliver Web Developer quality with SaaS Marketing outcomes. I cover REST API architecture as a Full Stack Developer, NextJS Developer optimization, WordPress Developer customization, and Mobile App Developer delivery. Serving 70+ SaaS Developer clients across 7 countries, 30% return to work with me again as their SaaS Developer for their next startup project. I build AI-native systems with a SaaS Marketing focus. Every SaaS Developer and Software Developer engagement I take on ships with business metrics first. As a SaaS Developer and Full Stack Developer: $400K+ Upwork | 100% Job Success - founder-led delivery. ⚙ TECH STACK - FULL STACK DEVELOPER & MVP DEVELOPER ARSENAL AI & Integration: as a Full Stack Developer I rely on Claude Code, OpenAI, FastAPI, LangChain - NextJS Developer compatible Frontend: React, TypeScript, NextJS Developer tools, Vue.js Backend: Python Full Stack Developer stack: FastAPI, Django, Node.js, GraphQL, PostgreSQL DevOps: AWS, DigitalOcean, Docker, Kubernetes Every Full Stack Developer and MVP Developer project I take on includes this complete toolkit. I work as a NextJS Developer, WordPress Developer, and Mobile App Developer specialist, alongside my Python Full Stack Developer and Software Developer skills - optimized for WordPress Developer flexibility and SaaS Marketing success from day one of your startup project.

📢 Available for New Projects 📢 I am a Senior Java Developer and Full Stack Developer with 10+ years of experience building production-grade backend systems, SaaS platforms, and web applications that scale globally. As a Java Developer and Full Stack Developer, I specialize in transforming complex business requirements into reliable, high-performance software solutions. Why hire me as your Java Developer and Full Stack Developer? ⭐ 100% Job Success Score ☕ 10+ years of commercial Java development across enterprise and startup environments 🚀 30+ production systems - SaaS platforms, web apps, APIs, and microservices ⚙️ Expert Java Developer in Spring Boot, Spring Cloud, Hibernate, and microservices 💰 Built fintech Java backend processing $15M+ annually on AWS 📈 Scaled logistics platform to 1.2M+ daily API requests with Redis optimization 🏆 Delivered Full Stack Developer MVP in 6 weeks securing $500K+ pre-seed funding 🖥️ Full Stack Developer - Java backend + React + Node.js + REST API ☁️ AWS, Docker, Kubernetes, CI/CD pipelines 🗄️ PostgreSQL, MySQL, MongoDB ✅ TDD, SOLID principles, clean architecture, Agile 👥 Led 10+ developer teams across full-cycle SaaS delivery What I build as a Java Developer and Full Stack Developer: As a Java Developer, I design backend systems, REST APIs, and microservices that power SaaS platforms, web applications, and enterprise software. As a Full Stack Developer, I cover the complete stack - Java Spring Boot backend, PostgreSQL database, React frontend, and AWS cloud deployment. I have delivered SaaS platforms, CRM systems, ERP solutions, marketplace platforms, booking systems, fintech applications, healthcare platforms, logistics systems, and EdTech products. Industries served: 🏦 Fintech - payment processing, financial SaaS, embedded financing 🏥 Healthcare - HIPAA-compliant platforms, patient management systems 🚚 Logistics - real-time tracking, fleet management, delivery platforms 🛒 E-commerce - marketplace platforms, inventory and order systems 📚 EdTech - learning management systems, educational SaaS platforms 🏗️ Construction - project management, field operations, procurement 📊 SaaS - multi-tenant architecture, subscription billing, dashboards Technical expertise: Backend: Java, Spring Boot, Spring Cloud, Spring Security, Hibernate, Microservices, REST API, Kafka, Redis, OAuth2, JWT Full Stack: React, Next.js, TypeScript, Node.js, NestJS, Redux, Tailwind CSS Cloud: AWS (EC2, S3, RDS, Lambda), Docker, Kubernetes, Jenkins, GitHub Actions, Terraform Databases: PostgreSQL, MySQL, MongoDB, Redis, Elasticsearch Integrations: Stripe, Plaid, Firebase, Twilio, QuickBooks, OpenAI API, Claude API What I deliver: ✅ SaaS platform development from MVP to production ✅ Web application development and modernization ✅ REST API design and microservices architecture ✅ Third-party API integrations ✅ Fintech and payment system development ✅ Marketplace and booking platform development ✅ Custom CRM, ERP, and internal tooling ✅ Cloud infrastructure setup and optimization As a Java Developer and Full Stack Developer, I think about architecture, scalability, and maintainability from day one. Whether you need a Java Developer for a critical backend service, a Full Stack Developer to build your SaaS platform, or a technical partner to architect your web application - I deliver production-ready results. Looking for a Java Developer, Full Stack Developer, Spring Boot Developer, SaaS Developer, or Web Application Developer who builds systems that scale? Just drop me a message

AI mobile apps have become the primary way businesses connect with customers, streamline operations, and accelerate growth. As a Mobile App Developer (React Native, Flutter, Kotlin, Swift), I help startups, growing companies, enterprises transform ideas into scalable mobile products that deliver measurable business value. Whether you’re building a new application or modernizing an existing one, I focus on creating high-quality solutions powered by modern technologies and AI For more than 10 years, our team has been designing, developing, and scaling mobile products for companies worldwide. We combine the expertise of Mobile App Developer specialists, React Native engineers, Flutter developers, iOS Developer professionals, and Android developers to build secure, scalable, and user-friendly mobile applications. Our experience also includes AI-powered features, backend development, API integrations, and cloud-native architectures Our company metrics: • 10+ years of software development experience • 200+ successfully delivered projects • 20,000+ tracked hours on Upwork • 40+ software engineers and mobile specialists • $1M+ earned through successful client engagements • 5+ years average commercial experience per developer As a Mobile App Developer (React Native, Flutter), I work closely with founders to define product strategy, validate ideas, and deliver production-ready applications. Our team builds cross-platform solutions using React Native and Flutter, as well as native applications for iOS Developer and Android environments. We also integrate AI capabilities where they create real business value, helping companies automate workflows, personalize user experiences, and improve operational efficiency Our projects range from startup MVPs to enterprise platforms supporting thousands of users. Every Mobile App Developer on our team collaborates with experienced Flutter developers, React Native engineers, Android developers, iOS Developer specialists, full stack developer teams, web developer professionals, and backend engineers to deliver reliable products from concept to launch We specialize in mobile app development across healthcare, fintech, logistics, education, marketplaces, SaaS, workforce management, and customer engagement platforms. Whether the project requires Flutter, React Native, or native Android and iOS development, our focus remains the same—building applications that are fast, secure, intuitive, and ready to scale Our expertise extends beyond coding. We help clients choose the right architecture, define product roadmaps, optimize user experience, and integrate AI-powered functionality into existing and new mobile products. Working alongside flutter developer, android developer, iOS developer, web developer, full stack developer teams allows us to deliver complete end-to-end mobile solutions instead of isolated development services We regularly build AI mobile applications using React Native, Flutter, Java, Kotlin, Swift, React, Python, Kotlin, and Laravel, integrating secure APIs, cloud services, payment systems, authentication, push notifications, analytics, and AI-powered automation. Every Mobile App Developer on our team understands how to create applications that perform consistently across Android and iOS devices while maintaining excellent user experiences Every Mobile App Developer (Android, iOS) on our team focuses on building products that combine outstanding performance, scalability, and long-term maintainability. Using React Native, Flutter, Swift, native Android, and iOS Developer best practices, we create applications that support rapid business growth and evolving customer needs. Our full stack developer, web developer, flutter developer, and android developer teams collaborate throughout the entire product lifecycle, while AI technologies help deliver smarter mobile experiences, personalized recommendations, intelligent automation, and data-driven decision making AI has become an important part of modern AI mobile app development. We help businesses integrate AI into mobile products (Android, iOS) through intelligent assistants, automation, predictive features, recommendation engines, and AI-driven user experiences. Instead of adding AI as a trend, we implement practical solutions that improve customer engagement and simplify business operations Whether you need a Mobile App Developer to launch a new MVP, migrate an existing application to React Native or Flutter, modernize an Android Kotlin application, improve an iOS Swift product, or expand your engineering team, we can help. Our experience covers the entire product lifecycle—from discovery and architecture to development, testing, deployment, and long-term support If you’re looking for a trusted Mobile App Developer with expertise in React Native, Flutter, iOS Developer, Android, Swift, Kotlin, and scalable mobile app development, let’s discuss your project and build a solution that creates lasting business value