Kanstantsin K.

I am a Senior Full-Stack .NET Developer with 10+ years of experience building scalable SaaS platforms, enterprise applications, cloud-native backends, and AI-powered solutions. I specialize in modern Microsoft technologies including .NET 10, .NET 9, ASP.NET Core, Minimal APIs, Clean Architecture, CQRS, SignalR, Hangfire, OpenTelemetry, and distributed backend systems using MassTransit. I help startups and enterprise clients build high-performance applications from architecture and backend APIs to modern front-end interfaces and cloud deployment pipelines. Core Expertise Backend & Cloud Development - .NET 10 / .NET 9 / ASP.NET Core - REST APIs & Minimal APIs - Clean Architecture & CQRS - SignalR real-time applications - Background processing with Hangfire - Distributed systems & event-driven architecture - OpenTelemetry observability - MassTransit messaging - Authentication & authorization systems - Multi-tenant SaaS architecture Front-End Development - React - Angular (2+ through latest versions) - TypeScript - Material UI - Responsive web applications Cloud & DevOps - Azure - Docker - Azure DevOps - GitHub Actions - Nginx - CI/CD pipeline automation Databases & Infrastructure - PostgreSQL - Redis - Elasticsearch - CosmosDB - SQL Server AI & Automation - AI Agents - AI workflow automation - Semantic Kernel - AI-assisted business applications - Process automation solutions Integrations I have extensive experience integrating third-party APIs and business platforms including: - Stripe - Twilio - Google APIs - Cloudflare - Slack - Facebook APIs - CallTrackingMetrics - Yelp - Yext Additional Expertise - SaaS platforms - CRM/ERP systems - Ecommerce applications - Healthcare platforms Browser automation - CAPTCHA solving - Advanced web scraping and data extraction systems I can work on both long-term product development and short-term high-priority projects. I focus on clean architecture, maintainable code, performance, and fast communication throughout the development process. If you need a senior engineer who can quickly understand business requirements and deliver production-ready solutions, feel free to contact me.