Nemanja Milenković-Senior / Lead AI Engineer | Applied GenAI, RAG, AI Agents & AI Platform Engineering
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Experience
AI Engineer / Senior Backend Engineer
Intelycx
Manufacturing intelligence platform with enterprise workflows, RAG, real-time AI assistant features, and multi-repository backend architecture.
- Built and extended production AI/backend services with Django, DRF, FastAPI, GraphQL, Celery, PostgreSQL, MySQL, Redis, and WebSockets across a modular multi-repository platform.
- Contributed to ARIS V2, a real-time manufacturing AI assistant using LangChain, LangGraph, MCP tool orchestration, planning/execution flows, OpenAI, AWS Bedrock, Qdrant, and Elasticsearch/OpenSearch-backed retrieval.
- Supported rollout expansion from ARIS V1 in 4 of 17 client production plants to ARIS V2 currently active in 13 of 17 plants, increasing real-world deployment coverage to more than 50% of the client footprint.
- Worked on document-grounded RAG functionality including ingestion, OCR, chunking, embeddings, indexing, retrieval, reranking, and grounded answer generation for industrial workflows.
Stack: Python, Django, DRF, FastAPI, LangChain, LangGraph, GraphQL, Celery, WebSockets, OpenAI, AWS Bedrock, Qdrant, Elasticsearch/OpenSearch, PostgreSQL, MySQL, Redis, Docker.
Senior Software Engineer
Nuromedia GmbH
Healthcare and parenting applications with API delivery, backend reliability, and Vision AI work for accessibility-focused product features.
- Tested and monitored multiple Vision AI models for a sign-language translation application for deaf and speech-impaired users, improving application recognition-response speed by more than 350%.
- Designed and maintained REST APIs and optimized MySQL schemas/queries to support reliable frontend/backend communication across multiple parallel projects.
- Helped organize internal guidelines for responsible AI-tool usage in engineering workflows, including practical use in coding, refactoring, and review.
Stack: PHP, REST APIs, MySQL, JavaScript, TypeScript, Vue.js, Vision AI model testing/monitoring, Git, Agile delivery.
Senior Software Engineer
LeasingMarkt.de
High-traffic automotive marketplace focused on backend performance, legacy modernization, caching, and product usability.
- Refactored legacy Laravel/PHP code and improved maintainability through cleaner database access, caching strategies, and API-connected product flows.
- Collaborated with UX/UI stakeholders on usability improvements in a live automotive marketplace while supporting practical AI-assisted development rules for the team.
Stack: PHP, Laravel, MySQL, Redis/caching, REST APIs, JavaScript, Vue.js, UX/UI collaboration, legacy modernization.
Senior Software Engineer
LILLYDOO GmbH
Subscription e-commerce platform with Symfony payment microservices and Vue.js admin-backend workflows under time pressure.
- Implemented a new Payone payment method inside the Symfony payment processor, contributing to a 15% increase in payment conversion rate.
- Added validation and authorization logic while keeping payment workflows secure, maintainable, and stable across admin/backend touchpoints.
Stack: PHP 8.2, Symfony 5, Vue.js 2, Payone API, Psalm, Rector, microservices.
Lead Software Engineer / Senior SDE
Ad Badger
High-load Amazon advertising data platform with large-volume synchronization, reporting workflows, dashboards, and AWS production delivery.
- Reworked Amazon advertising data synchronization, caching, and backend processing to cut long-running jobs from roughly 10 hours to roughly 10 minutes, improving operational throughput for a high-load reporting platform.
- Worked across backend and frontend concerns to expose complex advertising data in usable product experiences for paying customers.
Stack: PHP, Laravel-style architecture, MySQL, Redis, AWS EC2, RDS, S3, SQS, queues, batching, parallel processing, React, reporting workflows.
Senior Web Application Engineer
Curaytor
Mature SaaS platform undergoing incremental modernization toward microservices and distributed delivery.
- Contributed to the launch of a new microservice platform that helped scale the customer base from around 110 to nearly 400 clients within the first three months.
- Supported safer incremental modernization of a live SaaS product without disrupting day-to-day product delivery during rapid customer growth.
Stack: PHP, JavaScript, REST APIs, MySQL, Redis, AWS, microservices, API gateway patterns, SaaS product delivery.
Founder & Lead Engineer
Green Line Trading LTD
Software consultancy focused on client delivery, backend systems, e-commerce, AWS migration, and modernization.
- Founded and led delivery for clients including Curaytor, Whatagraph, and Ad Badger, owning architecture, milestones, stakeholder communication, and junior mentoring.
- Helped modernize monoliths toward microservices-oriented architecture and AWS-backed production delivery.
Stack: PHP, Laravel, Symfony, MySQL, PostgreSQL, Redis, AWS, Docker, REST APIs, project management.
Industry Experience
See where this freelancer has spent most of their professional time.
Experienced in Information Technology, Retail, Advertising, Manufacturing, Healthcare, and Automotive.
Business Area Experience
See which departments and functions this freelancer has contributed to most.
Experienced in Information Technology, Product Development, Project Management, Business Intelligence, Operations, and Quality Assurance.
Summary
Senior AI Engineer and technical lead with 20+ years of production software experience and a recent hands-on focus on applied GenAI, RAG, AI agents, Vision AI, tool-enabled LLM workflows, and backend-connected AI systems. I build AI features that are tied to real product workflows, not demos: industrial manufacturing assistants, document-grounded retrieval, sign-language recognition workflows, AI-assisted vehicle-service products, and high-load data platforms.
I combine Python, Django, FastAPI, LangChain, LangGraph, Qdrant, Elasticsearch/OpenSearch, AWS Bedrock, OpenAI, Docker, SQL, Redis, and strong backend architecture depth. Recent measurable outcomes include expanding ARIS V2 AI-assistant deployment from 4 of 17 to 13 of 17 production plants, improving Vision AI recognition-response speed by more than 350%, increasing payment conversion by 15%, and cutting high-load synchronization jobs from roughly 10 hours to roughly 10 minutes.
Skills
Applied Ai: Genai, Rag, Ai Agents, Mcp, Tool Calling, Langchain, Langgraph, Openai, Aws Bedrock, Grounded Enterprise Ai Workflows
Ai Backends: Python, Django, Drf, Fastapi, Graphql, Celery, Websockets, Modular Services, Production Apis, Multi-Repository Delivery
Retrieval Systems: Ocr, Chunking, Embeddings, Indexing, Vector Search, Reranking, Qdrant, Elasticsearch/Opensearch, Pgvector, Faiss
Vision Ai: Model Testing, Monitoring, Sign-Language Recognition Workflows, Camera-Oriented Products, Object Recognition Experience
Architecture: Microservices, Modular Monoliths, Api Gateway Patterns, Distributed Data, Queues, Pragmatic Legacy Modernization
Leadership: Founder And Lead Roles, Mentoring, Standards Setting, Technical Ownership, Stakeholder Communication, Production Delivery
Ai / Llm: Openai, Aws Bedrock, Deepseek Api, Langchain, Langgraph, Rag, Ai Agents, Mcp, Tool Calling, Ocr, Embeddings, Vector Search, Reranking, Document-Grounded Workflows
Vision Ai: Sign-Language Recognition Workflows, Model Testing/Monitoring, Camera-Oriented Ux, Object Recognition, Google Vision, Azure Vision, Tensorflow Experience
Backend: Django, Drf, Fastapi, Celery, Laravel, Symfony, Laminas, Rest Apis, Graphql, Websockets
Data / Retrieval: Postgresql, Mysql, Redis, Elasticsearch, Opensearch, Qdrant, Pgvector, Faiss, Dynamodb
Cloud / Devops: Aws Bedrock, Ec2, Rds, S3, Sqs, Opensearch, Docker, Linux, Ci/Cd, Github Actions, Production Support
Architecture: Ai Platform Engineering, Microservices, Modular Monoliths, Api Gateway Patterns, Queues, Batching, Parallel Processing, Legacy Modernization
Domains: Industrial Ai, Healthcare Accessibility, Automotive, E-Commerce, Saas, Marketing Analytics, Legal Tech
Languages
Education
Masterschool
AI Engineer Program · Berlin, Germany
University of Novi Sad, Faculty of Technical Sciences
Master's in Information Technology · Information Technology · Novi Sad, Serbia
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