Sebastian P.

Generative AI Engineer | Expert-Vetted | 7+ years | LLM | ML | NLP

Top 1% freelancer on Upwork: Senior (Gen) AI Specialist (Expert Vetted by Upwork): I help companies build, deploy, and scale production-grade AI systems, from first prototype to enterprise rollout. 100% Job Success on Upwork. Former Director of AI at Hyperstack / NexGen Cloud (GPU cloud platform) My work spans the full AI lifecycle: scoping the right approach, building working prototypes fast, and engineering systems that hold up at scale. I've done this across LLM platforms, computer vision apps, pricing models, and more. 🏗️ How I work: 1. Start simple. 2. Ship a working prototype fast. 3. Iterate toward scalable production. 4. Communicate clearly and transparently. 📈 What I've delivered (selected) ⬥ Hyperstack AI Studio: end-to-end platform for building, fine-tuning, and deploying custom LLMs on cloud GPUs. ⬥ NVIDIA GTC 2024 speaker: presented on GPU selection and throughput optimization for open-source LLMs to a global AI audience. ⬥ LLM chatbot optimization on AWS SageMaker: improved output quality using RAG patterns and cost-effective scaling. Client review: "extremely knowledgeable, detailed and fast." ⬥ GPU-accelerated containerization (Docker + NVIDIA Toolkit): GPU Infrastructure optimization. Client review: "understood requirements and went above and beyond." ⬥ Generative AI recruitment automation: built an LLM-powered pipeline combining process mining with automated candidate evaluation. ⬥ Transformer-based pricing optimization: developed competitive pricing models using transformer architectures. ⬥ Deforestation risk prediction: built geospatial ML models for environmental risk assessment at Deloitte. ⬥ Published in ACM: peer-reviewed research on ML-based mobile malware detection. Won the Joop Bautz Award for best information security thesis in the Netherlands (2018). 💬 What clients say ★ "Sebastian was key to the success of this project." ★ "Very knowledgeable in LLMs/AI. Extremely professional, quick, and his communication was very impressive." ★ "Demonstrated professionalism, dedication, and significant effort to deliver quality work." ★ "Solved a very difficult problem quickly and efficiently." 🎓 Credentials ✻ MSc Data Science & Business (Cum Laude) — University of Twente ✻ Google Cloud Professional Data Engineer ✻ Microsoft Azure Data Scientist Associate ✻ MLOps Engineering Specialization (DeepLearning.AI) ✻ Machine Learning (Stanford University) ✻ Joop Bautz Information Security Award (2018) 🛠️ What I work with ☛ LLMs & Generative AI — fine-tuning, RAG, inference optimization, vLLM, LangChain, OpenAI API, Hugging Face ☛ Cloud & Infrastructure — AWS (SageMaker), Azure, GCP, Databricks, Docker, Kubernetes, Terraform ☛ ML & Data Science — PyTorch, TensorFlow, Scikit-learn, computer vision (OpenCV, YOLO), NLP (SpaCy, NLTK) ☛ Languages — Python, JavaScript, Java, R, SQL 🤝 Why clients choose me ✔︎ Expert-Vetted by Upwork (Top 1% of freelancers) ✔︎ 100% job success rate across 19 Upwork projects ✔︎ Former Director of AI: I bring leadership-level thinking to every engagement ✔︎ NVIDIA GTC speaker: recognized by the global AI community ✔︎ Fast prototyping to production-grade systems ✔︎ Clear communication: clients consistently highlight this ✔︎ Published researcher and award winner Let's talk about your AI challenge!