GenAI
Loomi Brain
An AI knowledge/reasoning system focused on intelligent information retrieval, memory, and assistant-like workflows.
Explores how AI systems can retrieve, organize, and reason over information in assistant-like workflows.
Gregory Barmpas
I design and deploy machine learning, forecasting, retrieval, NLP, and LLM applications - from experimentation to scalable production APIs.
Data Scientist / AI Engineer with 4+ years of experience developing machine learning, demand forecasting, predictive analytics, and Generative AI solutions. Experienced in statistical modeling, ensemble learning, time-series forecasting, NLP, LLM applications, RAG systems, and production AI systems. Strong background in Python, SQL, scikit-learn, PyTorch, FastAPI, cloud technologies, and end-to-end AI solution delivery.
4+ years experience
Generative AI & LLM applications
RAG / semantic search systems
Forecasting & predictive analytics
Production AI APIs
Python / SQL / FastAPI / cloud
Featured work prioritizes production AI systems, retrieval infrastructure, NLP internals, and full-stack deployment readiness.
GenAI
An AI knowledge/reasoning system focused on intelligent information retrieval, memory, and assistant-like workflows.
Explores how AI systems can retrieve, organize, and reason over information in assistant-like workflows.
Full-stack
A full-stack Next.js game with PostgreSQL-backed questions, voting, mode selection, Prisma migrations, seed/import tooling, and database-level duplicate prevention.
Provides an engaging question-based voting game with persistent data and scalable question management.
Retrieval
End-to-end local retrieval pipeline with BM25, FAISS dense search, hybrid ranking, a custom scikit-learn feature reranker, evaluation metrics, CLI tooling, and Streamlit demo.
Improves document retrieval quality by combining sparse search, dense search, and learned reranking.
ML Infrastructure
A lightweight educational vector database built from scratch in Python, featuring dense vector storage, metadata filtering, exact similarity search, graph-based approximate search, and JSON persistence.
Shows how vector databases work internally, including indexing, metadata filtering, and approximate search.
NLP
Fine-tuning domain-adaptive Sentence-BERT embedding models for semantic search, retrieval, product search, support ticket matching, and job/CV matching.
Improves matching and retrieval quality by fine-tuning embeddings for specific domains and similarity tasks.
NLP
Advanced tokenizer engineering project implementing BPE, byte-level BPE, WordPiece, and SentencePiece-style unigram tokenization, with benchmarking against Hugging Face tokenizers and API/demo tooling.
Explains and implements the core tokenization algorithms behind modern language models.
Systems that retrieve, rank, and generate grounded answers from private or domain-specific knowledge.
AI assistants for document processing, information retrieval, decision support, and workflow automation.
Demand forecasting, backtesting, model monitoring, and predictive ML pipelines for business planning.
Embeddings, tokenizers, vector search, rerankers, APIs, and ML systems built from first principles.
Deus Ex Machina
Sep 2025 - Current
Dataviva
Nov 2022 - Oct 2024
Veltio
Oct 2021 - Nov 2022
School of Informatics | Aristotle University of Thessaloniki
Oct 2021 - Sep 2024
Malardalen University
Jan 2021 - Jun 2021
School of Informatics | Aristotle University of Thessaloniki
Sep 2017 - Sep 2021
Contact
Reach out for Data Science, AI Engineering, LLM application, retrieval, or forecasting roles.