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Dear Sir or Madam, My name is Oleksandr Prognimak. I have been working as a software developer for 33 years. I have extensive and longstanding experience in the following programming languages, frameworks, libraries, and technologies. Currently, my main focus is on the following IT areas: Java, JEE, Spring, Spring Boot, Angular, HTML5, JavaScript, TypeScript, CSS, SQL, PL/SQL, Docker, JUnit, Mockito, WireMock, Pact io, Maven, Oracle, PostgreSQL, and Azure Cloud. Here is the complete list of my skills: Skills, consulting, and development as a freelancer in the following areas: - Java: JDK 1.1 - 21, JSE, Swing, AWT - JEE: J2EE, JEE5,6,7,8,10 (Servlet, CDI, EJB, JPA, JMX, JMS, JSF) - Spring/Spring Boot: Spring Core, Spring Boot, Spring Test, Spring Data, Spring Integration, Spring Batch, Microservices - Cloud: Azure, AWS - Web Development/UI: Angular 4,7,10,16; Vue.js 2,3; TypeScript, GWT, Vaadin, JSP, JSF (RichFaces, PrimeFaces), HTML4, HTML5, JavaScript, JQuery, AJAX, Struts, Spring MVC - Web Services: SOAP, SOA, RESTful, Rest-API, OpenAPI, Swagger, RestEasy, Jersey, JSE HttpClient - ORM: Hibernate, EclipseLink, Apache OpenJPA - RDBMS/SQL: Oracle, Postgres, MySQL, MS-SQL, SQL, PL/SQL, MS Access, Teradata, H2 - App. Server/Servlet Container: Apache HTTP, Apache Tomcat, JBoss, Wildfly, Websphere, OC4J - XML Processing: AXIS-2, XPath, XSLT, XML Schemas, JAXP, JAXB - Build Tools: ANT, Maven, Gradle, Mojo - Source Code Management: GIT, GitLab, GitHub, Bitbucket, SVN, CVS - Case Tools/UML: Magic Draw, Software Architect, Together, ERWin, RationalRose - Report Tools: Jasper Report, BIRT Reports, Oracle Forms and Reports, Eclipse BI-Reports - Security: Java Security, JSSE, PKI, Websecurity, X509 - Test Tools/Testing: JUnit, TestNG, Cucumber, JBehave, Mockito, WireMock, EasyMock, Spring Test, Pact io, LoadTest, IntegrationTest, CI - MS-Office: VB, VBA, Excel-VBA, Access-VBA - Container Virtualization: Docker, Docker-Compose, Swarm, Kubernetes (K8) - Big Data: Apache Kafka, Zookeeper - Very Old Skills: C, C++, Basic, Pascal I am available immediately. Best regards, Oleksandr Prognimak

💼 Python Developer | Python Django | Python Web Scraping | Python Full Stack Developer | Python AI | Python Automation 🏆 TOP RATED PLUS | 💰 $5M+ Client Revenue | 💼 111+ Projects Delivered | ✅ 11,000+ Upwork Hours 💡 Clients Achieved: 🚀 Raised $4.9M+ / $9.4M+ / $6M+ after product development 📈 Scaled platforms to millions of users & billions of operations ⚡ Reduced system load & response time with optimized Python architectures 💰 Automated payments, workflows, and analytics → higher ROI & efficiency 🏥 Built secure, compliant systems (HIPAA, GDPR) used by global organizations I am a Python Developer, Python Full Stack Developer, Python AI Developer, and Python AI Engineer with 10+ years of experience building scalable web platforms, SaaS products, AI systems, and high-performance backend architectures. As a Python Developer, I specialize in designing clean architecture, scalable systems, performance optimization, and production-ready solutions that support real business growth. I work as a Python Full Stack Developer (Python + React / Next.js), combining powerful backend engineering with modern frontend development to deliver complete end-to-end applications. My expertise includes Python Django development, Flask development, and FastAPI development, building robust APIs, microservices, and distributed systems. I am also a Python Automation Engineer and Python Web Scraping Specialist, building intelligent automation systems, data extraction pipelines, and large-scale Python web scraping solutions for business intelligence, analytics, and AI-driven data processing. I design reliable scraping architectures that handle complex, high-volume data at scale. As a Python AI Developer, I build AI-powered applications, NLP systems, automation workflows, and data-driven intelligent platforms integrated with modern Python frameworks and cloud infrastructure. ⚡ Core Expertise as a Python Developer Python Full Stack Development (Python + React / Next.js) Python Django Developer, Flask Developer, FastAPI Developer Python AI Development & Machine Learning Integration Python Automation Engineering for business workflows Python Web Scraping & Data Extraction Systems Scalable backend systems, APIs, and microservices Cloud & DevOps (AWS, Docker, CI/CD pipelines) High-performance, production-grade Python systems 🚀 Selected Projects The Skills ($4.9M raised) 🎓 – Built and scaled an e-learning platform with payments, subscriptions, and mobile apps. As a Python Developer, helped launch a product used by thousands of users worldwide. Veeqo (acquired by Amazon) 📦 – Developed retail infrastructure processing £1B+ in orders. Optimized backend performance, integrated Stripe, and reduced server load using AWS Lambda as a Python Developer. Creyos (75K+ users, healthcare) 🏥 – Built a HIPAA-compliant cognitive assessment platform used by global research institutions. As a Python Developer, worked on secure data systems, scaling, and performance. CityFALCON ($6M raised) 📊 – Created a real-time NLP-powered financial news platform processing millions of articles daily. Designed scalable backend architecture as a Python Developer. ⚡ What I Deliver as a Python Developer Clean, scalable Python AI systems and backend architectures High-performance Python Django / Flask / FastAPI applications Python Full Stack Development (React / Next.js integration) Python Automation & Python Web Scraping solutions AI-powered Python applications and intelligent workflows Secure, compliant systems (GDPR, HIPAA-ready architectures) End-to-end product delivery from idea to production Client Testimonials ⭐⭐⭐⭐⭐ “Very professional! Pleasure to work with. Will definitely use again.” ⭐⭐⭐⭐⭐ “Super reliable, fast, and with clean, well-structured code. Communication was smooth and always on time.” ⭐⭐⭐⭐⭐ “Very satisfied with the work.” 💼 Why Clients Work With Me 10+ years of proven experience as a Python Developer Strong expertise in Python Full Stack, Python AI, and Python Web Scraping Ability to scale systems from MVP to enterprise-level platforms Deep understanding of backend architecture and system design Reliable communication and predictable delivery 🚀 Let’s talk about your project - I am available as your Python Developer, Python Full Stack Developer AI React, Python AI Developer, Python Automation Engineer, Python Django Developer, and Python Web Scraping Specialist.

⭐️ 8+ Years in Software Engineering (Golang, Python) ⭐️ Hands-on LLM/ChatGPT/RAG product development and large-scale ML hosting on AWS ECS/CDK ⭐️ Backend for global platforms serving 3M+ users/day ⭐️ CKAD, AWS Solutions Architect – Associate & AWS DevOps Engineer – Professional certified ⭐️ Strong background in microservices, cloud-native systems & real-time data pipelines ⭐️ Slack-JIRA AI assistant, Foodpanda homescreen infra, Amazon PDP localization pipeline ⭐️ High-impact Upwork client results with consistent 5.0 ratings 🧑‍💻 Back-End Engineering (Golang, Python) ☑️ REST, gRPC, GraphQL API design ☑️ Go frameworks: Gin, Echo, Revel, Martini, Gorilla ☑️ ORM: Gorm, go-pg | Testing: GoMega, Ginkgo, go-mock ☑️ Concurrency: goroutines, channels, worker pools ☑️ Dependency Injection: go-wire ☑️ Structured logging: zap, zerolog, logrus ☑️ GolangCI-lint contributor – deep attention to clean code and linting 🧑‍💻 Cloud & Infrastructure ☑️ AWS: Lambda, ECS, RDS, DynamoDB, S3, API Gateway, Secrets Manager, CDK ☑️ GCP: Cloud Run (standalone & GKE), Firestore, Pub/Sub ☑️ Infrastructure as Code: Terraform, Ansible ☑️ Docker, Kubernetes (CKAD), Helm ☑️ CI/CD: GitHub Actions, Jenkins, Bitbucket Pipelines 🧑‍💻 Databases & Caching ☑️ PostgreSQL, MySQL, MongoDB, DynamoDB, Firestore ☑️ Redis, Memcached, Key-vault ☑️ Neo4j (graph db), Elasticsearch (search & analytics) 🧑‍💻 DevOps, Observability, Streaming ☑️ RabbitMQ, Apache Kafka, Apache Schema Registry ☑️ Prometheus, Grafana, Datadog, AWS CloudWatch ☑️ Log pipelines: ELK (Elasticsearch, Logstash, Kibana), Filebeat 🛠 Blockchain & Decentralized Systems ☑️ Ethereum, Web3 API, ERC-20 Token Transfers ☑️ Cowswap DEX integration ☑️ Katzenpost Mixnet-based Ethereum transaction privacy router ☑️ Secure wallet interaction, order book access, token tracking 🧑‍💻 AI / GenAI / LLM Work ☑️ LangChain, ChatGPT, Retrieval-Augmented Generation (RAG) ☑️ Slack-JIRA LLM assistant (LangChain + Python + ChromaDB) ☑️ TruthWatch: Real-time YouTube AI content audit web app ☑️ Amazon-scale LLM hosting & PDP localization pipeline ☑️ Prompt engineering, LLM pipelines, context chaining

Senior AI & Full-Stack Developer with 8+ years of experience shipping production web applications across SaaS, healthcare, real estate, and e-commerce. I build AI-powered products with LangChain, LangGraph, OpenAI, and RAG pipelines that handle thousands of queries daily and the full-stack React, Node.js, and Python platforms around them. I work best with founders and teams who need one full-stack developer who can own the whole thing: backend, frontend, AI integration, cloud deployment, and the technical architecture decisions in between. No handoffs, no "that's not my part." ━━ WHAT I CAN HELP YOU WITH ━━ - AI integration & LLM development: RAG search, AI chatbots, AI agents, AI multi-agent platforms, document Q&A, recommendation engines, semantic search, LangChain workflows, OpenAI and Anthropic Claude API integrations - SaaS development: multi-tenant architecture, Stripe subscription billing, RBAC, real-time dashboards, full React + Node.js or Next.js and FastAPI stacks - Scaling & rescue projects: performance optimization, refactors, cloud migration to AWS or GCP, technical debt cleanup, microservices architecture - HIPAA-compliant healthcare apps: telemedicine platforms, patient portals, secure data handling, audit trails - Marketplaces, booking systems, property portals (PropTech), and e-commerce stores with Stripe payment integrations ━━ SELECTED PROJECTS ━━ Pirn.ai: AI Blood Test Recommendation Engine (HealthTech / AI) Built an AI-powered platform that recommends personalized blood tests and generates patient health reports from symptoms. Used by major diagnostic labs in Sweden. OpenAI, LangChain, RAG pipelines, and vector databases tuned for medical-grade reliability. AttendAnywhere: NHS Telemedicine Platform (MedTech) Contributed to a HIPAA-compliant video conferencing application used by the UK's NHS. Focus areas: scalable architecture, low-latency real-time video, and patient privacy at national scale. Numastays: Property Booking & Self Check-In (PropTech / SaaS) Rebuilt the booking flow and user journey for a large rental platform. Delivered multi-property booking, self check-in/check-out, and real-time availability — with measurable gains in conversion and operational efficiency. CheckView: AI-Powered E2E Testing SaaS Platform (SaaS / AI) Built an end-to-end testing platform with AI test planning, AI test generation, and self-healing tests that adapt when UI selectors change. Includes an AI-powered test step generator, scheduled cron job execution, public developer API, and Stripe subscription billing across monthly and annual plans. Works on WordPress and custom sites. ━━ TECH STACK ━━ AI & LLMs: LangChain, LangGraph, LlamaIndex, OpenAI API, Anthropic Claude API, RAG pipelines, vector databases (Pinecone, Chroma, pgvector), embeddings, semantic search, AI agents, prompt engineering, AI chatbot development Frontend: React, Next.js (App Router, Server Components), Vue.js, TypeScript, JavaScript, Tailwind CSS, shadcn/ui, Material UI, Redux Backend: Node.js, Nest.js, Python, FastAPI, Django, REST API, GraphQL, tRPC, PostgreSQL, MongoDB, Redis, Prisma, WebSockets, microservices Cloud & DevOps: AWS, GCP, Vercel, Docker, CI/CD, GitHub Actions, serverless architecture Integrations & Other: Stripe, Auth0, Firebase, Supabase, JAMstack, NextAuth, HIPAA compliance, multi-tenant architecture, real-time applications, MVP development, technical architecture, performance optimization, API integration, payment gateway integration, responsive design ━━ HOW I WORK ━━ I ask questions before I write code. I want to understand what you're actually trying to build and why. that's what separates a project that ships from one that drifts. You'll get clear daily updates, honest timelines, and code that's tested and documented so the next developer on it (you, your team, or a future hire) can pick it up without pain. I'm direct about what's realistic and what isn't. If something won't work, I'll say so early — not three weeks in. ━━ LET'S TALK ━━ If you have a project in mind, send me a message with a short description of what you're building and where you're stuck. I'll reply with honest thoughts on scope, approach, and whether I'm the right fit. Not every project is a match — and I'd rather tell you that upfront than waste your time.

I help startups and businesses design, build, and scale AI-powered applications, cloud-native platforms, and modern full-stack products. With 9+ years of Full-Stack Development and 5+ years of Cloud Architecture experience, I've worked with startups, agencies, and growing businesses to deliver scalable software, cloud infrastructure, and intelligent AI solutions. Since 2021, I've specialized in Artificial Intelligence, helping companies not only build AI-powered products from scratch, but also integrate AI capabilities into existing web and mobile applications. Whether you're adding AI chat, AI agents, workflow automation, document intelligence, recommendation engines, semantic search, or generative AI features, I can help implement solutions that fit naturally into your existing architecture. My expertise spans the complete product lifecycle—from architecture and infrastructure design to AI integration, backend development, deployment, monitoring, and production scaling. What I Can Help You With 🤖 AI Engineering & Automation - AI-powered SaaS applications - AI integration into existing products - AI feature development for web & mobile apps - AI Agents & Agentic Workflows - Workflow automation - LLM integrations (OpenAI, Claude, Gemini, Llama) - Retrieval-Augmented Generation (RAG) - AI Chatbots & Virtual Assistants - Knowledge Bases & Semantic Search - Prompt Engineering - Text, Image, Voice & Video AI - Custom AI Copilots - MCP (Model Context Protocol) - AI API integrations ☁️ Cloud Architecture & DevOps - AWS, Azure & Google Cloud - Cloud-native application architecture - Serverless solutions - Event-driven architecture - Infrastructure as Code (Terraform) - Docker & Kubernetes - CI/CD pipelines - Cloud migration & modernization - Performance optimization - Monitoring & Observability - High-availability systems - Cost optimization 💻 Full-Stack Development - Python (FastAPI, Django, Flask) - Node.js & TypeScript - React, Next.js, Vue.js & Angular - REST APIs & GraphQL - Microservices architecture - PostgreSQL, MySQL, MongoDB & Redis - Authentication & Authorization - Third-party API integrations - Performance optimization - Enterprise SaaS development 📊 Data & AI Infrastructure - Vector Databases - Pinecone, Weaviate & ChromaDB - AI Knowledge Bases - Semantic Search - Data Pipelines & ETL - AI Analytics - Recommendation Systems - Business Intelligence - Real-time Data Processing - Technology Stack - AI & Automation OpenAI • Anthropic Claude • Google Gemini • Llama • LangChain • LangGraph • CrewAI • AutoGen • MCP • RAG Backend Python • FastAPI • Django • Flask • Node.js • TypeScript • JavaScript • Express.js • REST API • GraphQL Frontend React • Next.js • Vue.js • Angular • Tailwind CSS Cloud & DevOps AWS • Microsoft Azure • Google Cloud Platform • Docker • Kubernetes • Terraform • CloudFormation • Cloudflare • CI/CD Databases PostgreSQL • MySQL • MongoDB • Redis • Supabase • Firebase Why Clients Work With Me ✔ Build AI-powered products from idea to production ✔ Integrate AI into existing applications without disrupting current workflows ✔ Design scalable cloud-native architectures ✔ Deliver clean, maintainable, and production-ready code ✔ Communicate clearly and work as a long-term technical partner ✔ Focus on measurable business outcomes—not just writing code I don't just develop software—I help businesses make the right architectural decisions, reduce technical risks, and build systems that continue to scale as the business grows. If you're looking for an AI Engineer who combines AI expertise, cloud architecture, and full-stack development to deliver reliable production systems, I'd be happy to discuss your project.

I am a Senior Penetration Tester (currently working at Mercedes-Benz) specializing in manual, deep-dive security assessments for web applications, APIs, and cloud infrastructure. I do not run automated scanners and hand over a 100-page PDF of false positives. I specialize in finding the complex, chained business-logic flaws, multi-tenant isolation issues, and authorization bypasses that automated tools completely miss. **Certifications:** - OSWE (Offensive Security Web Expert) - OSEP (Offensive Security Experienced Penetration Tester) - OSCP+ (Offensive Security Certified Professional) - OSWA, OSWP, KLCP **My Core Focus Areas:** - Web App & API Penetration Testing: Identifying IDORs, mass assignment, complex injection flaws, and authentication bypasses in modern SPAs and microservices. - Network Penetration Testing: Internal/External infrastructure assessments, Active Directory exploitation, and lateral movement. - Cloud Security: Exploiting access control misconfigurations in AWS, Azure, and GCP. **What you receive at the end of the engagement:** - Zero False Positives: Every vulnerability I report is manually verified and proven with exact reproduction steps. - Compliance-Ready Reporting: I deliver formal reports featuring accurate CVSS scoring, board-ready executive summaries, clear PoCs, and developer-centric remediation instructions. - Professional Discipline: I strictly adhere to established Rules of Engagement (RoE) to ensure zero business disruption during testing. Shoot me a message, and I’d be happy to share a redacted sample report so you can see the exact quality of work you will receive before we start.