Kostiantyn M.

High-performance backends. Decision engines. AI factories. Computer vision. Real-time systems. From UI/UX-heavy MVPs to full-stack platforms built for the traffic that comes after launch day, not just during it. Rust, C++, and 5+ languages. 100,000+ concurrent WebSocket connections -- in production. A 12-week roadmap shipped in 4. 30 senior engineers. Dedicated project teams, not rotating freelancers. Every engagement starts with a paid Discovery phase -- we scope the architecture before we write a line of code. Not a fit: no-code workflows, or projects solvable with Zapier. WHAT I BUILD - High-Performance Backends: Production backends with actix-web, axum, and Tokio -- millions of requests/day, zero GC pauses. REST, GraphQL, WebSocket, and gRPC services for throughput and latency-sensitive workloads. - Full-Stack Platforms: React, Next.js, TypeScript frontends with production backends -- SaaS, MVPs, and custom web applications from architecture to deployment. Designed for 1K to 100K concurrent users without a rewrite. - Autonomous AI Agents: Agentic pipelines with OpenAI and Anthropic Claude -- lead qualification, data analysis, customer support running 24/7. Multi-step reasoning, error recovery, state persistence. 11+ projects for one client. - Computer Vision: Object detection, tracking, real-time inference, OCR, document processing -- CUDA-optimized, deployed as production APIs or edge devices. Not Jupyter notebooks. - Real-Time 3D & Visualization: WebGL and WebGPU rendering -- product configurators, data dashboards, architectural viewers at 60fps in-browser on mid-range hardware. - Data Pipelines: Rust-native processing with Polars and DataFusion -- replacing Python/JavaScript bottlenecks. Kafka streaming, PostgreSQL persistence. - Cloud & Infrastructure: AWS, GCP, Azure with Terraform and Kubernetes -- auto-scaling, zero-downtime deployments, infrastructure-as-code. RECENT OUTCOMES - Crypto trading platform dropping connections above 8,000 users. Rebuilt proxy in Rust, Tokio, Kubernetes -- 100,000 connections at under 10ms, zero crashes. - GovTech blockchain payment router on Go. Rebuilt IAVL Tree in Rust -- 20–30% faster, Clutch-reviewed (Alex Kampa, AZKR Research). - Recruitment team spending 4 hours daily on manual data entry. Built automated extraction and processing pipeline -- 95% reduction. - Data analytics platform hitting memory limits in JavaScript. Replaced core with Rust and Polars -- 5x faster processing, 70% lower memory. - Blockchain gaming 3D pipeline loading in 8+ seconds. Rebuilt within 4GB RAM budget -- 45% faster, Clutch-reviewed (Ruslan Varets). TECHNOLOGIES - Systems & Backend: Rust, C++, Python, TypeScript, actix-web, axum, Tokio, Node.js, WebAssembly - Frontend: React, Next.js, TypeScript, Tauri, Dioxus - AI & Agents: OpenAI, Anthropic Claude, Hugging Face, LangChain, RelevanceAI - Graphics: WebGL, WebGPU, OpenGL, Vulkan, three.js, GLSL/WGSL shaders, bevy - Vision: OpenCV, CUDA, PyTorch, TensorFlow, Keras, Mediapipe - Data: Polars, DataFusion, PostgreSQL, Kafka, Snowflake, Apache Arrow - Cloud & DevOps: AWS, GCP, Azure, Terraform, Kubernetes, Docker, GitHub Actions - Networking: WebRTC, LibP2P, QUIC, WebSocket, gRPC Delivery: Discovery → Architecture Review → Platform Build → Performance Testing → Production Deploy → Runbook Handoff. Fixed scope per phase. This profile is for engineering teams building production platforms under real load. Send your project brief -- I'll reply within 48 hours to assess fit.