Sergiy Mirochnyk
AI Engineer · Vibe Coding · Agents & Full-Stack
I turn ideas into working products in days, not months — AI-assisted development with Claude Code & Cursor, multi-agent systems, RAG pipelines and full-stack delivery on infrastructure I deploy and secure myself.
Profile
AI Engineer with a 5+ year full-stack production background and a daily AI-assisted development workflow: I prototype with Claude Code, Cursor and Copilot, then harden what works into production systems. I design multi-agent architectures — an executor agent performs the task, a reviewer agent scores it, and the loop iterates until quality reaches ≥ 90% — plus RAG pipelines (pgvector, embeddings), MCP integrations connecting LLMs to internal systems, and n8n orchestration. Comfortable end-to-end: React / Next.js / Node.js / Python / TypeScript, PostgreSQL / SQL Server, fine-tuning open-source LLMs with Unsloth. I provision the VPS, deploy, monitor and secure everything myself — OWASP hardening included. Allergic to vendor lock-in.
Experience
Full-Stack Developer & AI Engineer
2023 — todayFIMAINFO — Software development & cloud solutions·Dijon, France
- Designed and shipped multi-agent AI systems for call-center campaigns: executor agents process tasks, reviewer agents score outputs and loop until ≥ 90% quality — cutting back-office hours by 80% on covered teams.
- Adopted an AI-assisted development workflow (Claude Code, Cursor, Copilot) for internal tools and proof-of-concepts — idea-to-working-demo cycles of days instead of sprints.
- Built RAG pipelines over internal business knowledge (embeddings + pgvector) and exposed company data to LLM agents through MCP-style integrations and REST APIs.
- Built n8n automations for recurring workflows: email parsing, ticket routing, invoicing, compliance filings, internal notifications.
- Fine-tuned open-source LLMs (Unsloth, LoRA / QLoRA) on business use cases; served from in-house GPU servers behind REST APIs for cost control and data sovereignty.
- Prompt engineering across commercial (OpenAI, Claude) and self-hosted models; routing between light specialized and heavy models to optimize token spend.
- Deployed statistics & monitoring agents on multi-tenant infrastructure — Grafana / Metabase dashboards, SLA alerts, anomaly detection — alongside security agents (auth, OWASP checks).
- Full-stack delivery throughout: SQL Server / T-SQL databases, Node.js REST APIs, responsive telephony UIs (Tailwind / JS), Jest testing.
Web Developer
2022 — 2023Novileads Co.·Ukraine · remote
- Built responsive marketing sites and web apps from Figma mockups (HTML, CSS, JavaScript, PHP).
- Front-end performance optimization, cross-device compatibility, shared component libraries with back-end developers and designers.
Web Developer — French Foreign Legion
2017 — 2021French Foreign Legion — Képi Blanc magazine & other Legion sites·France
- Built site components, managed content, coordinated with the editorial team; technical SEO, social integrations, performance optimization.
IT Technician
2011 — 2017French Foreign Legion — 1st R.E.G. / 1st R.E.·France
- Installed, configured and maintained hardware / software fleets for operational units.
- Network security: firewall & antivirus administration, system hardening, L1/L2 support.
Selected Projects
Executor / reviewer loop for call-center back offices. Saves 30+ h/week per team. Next.js · Claude API · Postgres · Docker
Inbox → structured JSON. Executor extracts, reviewer validates, n8n routes. Python · OpenAI · n8n
Multilingual EU-compliance workflow automation. Python · LangChain · Supabase
Statistics & security agents on multi-tenant infra. SLA tracking, anomaly alerts. Node · Grafana · Postgres
Real-time telephony API + analytics. T-SQL · REST · Node
Multi-exchange crypto bot — signal generation, risk management, back-testing. Python · WebSockets · Postgres