Siarhei Thor
AI/ML Engineer | Applied ML, LLM Systems & AI Product Infrastructure
Zurich, Switzerland | (+41) 78 217 35 65 | siarheithor@gmail.com
Last updated: May 28, 2026
Profile
AI/ML Engineer with hands-on experience building machine learning services, agentic LLM applications, and backend platforms for AI products. Strong in Python, FastAPI, Pydantic, scikit-learn/XGBoost, data pipelines, retrieval systems, and production-oriented ML workflows. Experienced in turning messy real-world data into reliable APIs, internal tools, and user-facing AI features, including AI-assisted coding systems with repo maintenance workflows, sandboxed tool use, reusable agent skills, and knowledge graph-backed knowledge bases. Combines applied ML engineering with product thinking, structured problem solving, and cross-functional delivery.
Experience
AI/ML Engineer
May 2024 - Present
- Developed end-to-end ML services for running and cycling analytics, spanning data preparation, model training, evaluation, calibration, deployment, monitoring, and automated retraining workflows.
- Built production prediction and analytics systems in Python with FastAPI, scikit-learn, XGBoost, pandas, and NumPy for endurance-sports use cases.
- Designed feature engineering and data-quality workflows for time-series data from sports wearables, including preprocessing, bad data detection and handling, and support for incomplete activity data.
- Built an AI-assisted event data management pipeline that enriches incomplete race listings into structured, validated RaceDB records using web search, scraping, schema-driven extraction, validation, and entity matching.
- Designed and prototyped AI-assisted training-planning and internal product prototypes for endurance-sports use cases, including structured knowledge handling and developer-facing tooling.
- Designed and built an LLM- and sports-analytics-based training feedback system with real-time insights and personalized recommendations, including custom training load metrics development for increased personalization.
- Developed AI coding-assistant workflows for repository maintenance, tool orchestration, sandboxed execution, reusable agent skills, and knowledge graph-supported project knowledge bases.
Data Scientist / AI Engineer
Sep 2023 - Apr 2024 Jun 2025 - Sep 2025, project-based
- Built conversational analytics products on top of survey datasets, including chat-based insight workflows that translate structured data into natural-language answers.
- Developed a multi-agent survey intelligence prototype combining semantic retrieval, SQL-based analysis, statistical guardrails, and user-facing chat interfaces.
- Implemented preprocessing pipelines for survey standardization, metadata generation, segmentation analysis, and vector-store creation for downstream retrieval.
- Created web and API layers for interactive analysis using FastAPI, WebSockets, DuckDB, pandas, scipy, and FAISS.
- Maintained and improved data pipelines for large survey datasets and helped prototype early dashboard-style product offerings.
AI Strategy and Digitalization Consultant
Sep 2021 - Aug 2023
- Advised architecture and real-estate clients on AI adoption, digital workflows, and product opportunities.
- Built applied AI prototypes including a GPT-powered regulatory assistant for architects, a Stable Diffusion / ControlNet workflow for design exploration, and digital tools for sustainability-focused planning analysis.
- Helped translate domain-specific business problems into practical AI-enabled workflows and MVP concepts.
Senior Architect / Computational Design
Jan 2015 - Oct 2021
- Led and contributed to large-scale building projects across Sweden and the Netherlands, coordinating complex design-development work across international teams, consultants, and clients.
- Used programming and parametric design tools to improve delivery quality, automate repetitive workflows, and support complex design coordination.
- Managed multidisciplinary teams and developed training material for junior architects in computational design and digital methods.
Technical Skills
Programming Languages
Python, SQL, R
ML, AI & Modeling Frameworks
scikit-learn, XGBoost, TensorFlow, PydanticAI, Pydantic, OpenAI-compatible APIs
Data & Analytics Libraries
pandas, NumPy, SciPy, DuckDB, FAISS, PyArrow, Optuna, Plotly
Application & Data Systems
FastAPI, SQLAlchemy, PostgreSQL, MySQL, Redis, WebSockets, Aiogram, Streamlit, Alembic, S3-compatible storage
Infrastructure, Observability & Tooling
Docker, Gunicorn/Uvicorn, Granian, OpenTelemetry, Langfuse, Sentry, pytest, Git, Linux, GCP
AI Coding Assistant Systems
Repository maintenance, agent skills, tool orchestration, sandboxed execution, coding-agent workflows, knowledge bases, knowledge graph-assisted context management
Soft Skills
Languages
English, Dutch, Swedish, and Belarusian: fluent. Russian: native proficiency.
Leadership & Project Management
International design-development coordination, multidisciplinary team leadership, stakeholder alignment across clients and consultants, workshop facilitation, mentoring, and structured delivery in complex projects
Selected Projects
Knowledge Hub
Jul 2025 - Jan 2026
- Built a modular AI platform for Telegram-based learning and productivity apps with shared backend infrastructure, plugin-based product logic, persistent user state, scheduling, and multi-provider LLM orchestration.
- Developed a German-learning product with CEFR-based onboarding, vocabulary progression, quizzes, reminders, and cached AI-generated learning content.
Education
MSc, Architectural Engineering — Delft University of Technology, The Netherlands
September 2009 - June 2014
Additional Education
Data Science Program — EC Education, Stockholm / Online
August 2023 - June 2024
Certifications
- Google Advanced Data Analytics, Coursera
- Deep Learning Specialization, DeepLearning.AI
- Machine Learning Specialization, DeepLearning.AI
- LLM Finetuning and Prompt Engineering, DeepLearning.AI
- IBM Data Science Specialization, Coursera
Additional
Interests: Orienteering, trail running, cycling, photography.