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Lev Ronzhin

ENTERPRISE AI ENGINEER

AI is my passion!
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«Don't know how to set up corporate AI and make it work for your business? I'm on my way!»

I design fault-tolerant corporate generative AI systems. My specialization is complex autonomous AI agents, building scalable in-house RAG architectures, and hardcore local inference of open-source models. I take on everything: from deep refactoring of corporate code to configuring queues and load balancers for LLMs under peak loads (300+ RPS).

Beyond server magic, I have a soft spot for automating routine tasks using custom AI apps. In my free time from vibe-coding, I test healthy recipes from the internet. Maybe I'll automate that one day too 😅

Core Competencies

GenAI, LLM & Inference

Tools: LangGraph, Agentic AI, LlamaIndex, LangChain.

Inference & LLMOps: Fine-tuning vLLM / llama.cpp for high loads. Load balancing and request proxying via LiteLLM, key rotation. Deep analytics and generation tracing via Langfuse.

Architecture: Model Context Protocol (MCP), Advanced / Graph RAG, Guardrails, HITL (Human-in-the-Loop).

Backend & Infrastructure

Development: Python, FastAPI, Asyncio. Creating CRUD services, refactoring corporate systems, systemic Code Review.

Databases & Queues: ClickHouse, PostgreSQL, Qdrant, Weaviate, ADQM, SAP HANA. Setting up message brokers for load balancing.

Deployment: Kubernetes, Docker, Apache Airflow, Prometheus, Grafana, GitLab CI/CD.

Work Experience

Severstal PJSC Senior AI / Tech Lead

11.2025 - Present | 20,000+ users | 300 RPS

Latest achievements:

  • Corporate in-house RAG: Designed and launched a custom in-house RAG (full CRUD service) from scratch with queues and load balancing, moving away from out-of-the-box solutions.
  • LLM Proxy & Analytics: Implemented LiteLLM for request proxying, load balancing, and key rotation. Configured Langfuse for transparent AI quality and performance analytics.
  • System Refactoring: Conducted massive refactoring of corporate AI system codebases and introduced strict Code Review standards. Upgraded local inference pipelines.
  • Multi-Agent Workflow: Developed a LangGraph-based system for natural language SQL generation across heterogeneous DBs (ClickHouse, Postgres) utilizing a custom thesaurus (15k terms) via Qdrant.

Miramedix Data Scientist (NLP)

12.2024 - 06.2025
  • Developed NLP pipelines and agentic systems based on the LlamaIndex framework tailored for the medical domain.
  • Implemented automated benchmarks to evaluate LLM response quality (Gemini, ChatGPT) using BERTScore, ROUGE, and BLEU metrics.
  • Designed databases for embedding caching and generated synthetic datasets.

Institute of Digital Transformation of Medicine

03.2022 - 11.2025 | Tech Lead / Data Scientist
  • Architected and implemented a corporate DWH contour from scratch (PostgreSQL, MongoDB, Neo4j, Apache Airflow).
  • Developed a CDSS prototype based on GraphRAG (Neo4j) and a medical RAG chatbot (FastAPI, Asyncio).
  • Conducted fine-tuning of local LLMs (LoRA, QLoRA) with inference optimization via vLLM and llama.cpp.