Sebastián Castaño
Verified Expert in Engineering
Data Scientist and ML Developer
Berlin, Germany
Toptal member since September 13, 2021
Sebastian has a PhD in AI/ML and over 10 years of experience in interdisciplinary projects across neuroscience, finance, marketing, and consumer products, among other domains. Experienced in designing and deploying end-to-end AI systems and leading teams to deploy production-ready solutions in enterprise and startup environments, Sebastian creates intuitive AI tools and data-driven insights that drive business impact by combining deep technical expertise with actionable results.
Portfolio
Experience
Availability
Preferred Environment
Visual Studio Code (VS Code), Git, Docker, MacOS, cursor, Python, Amazon Web Services (AWS)
The most amazing...
...project I've developed was an ML-based, closed-loop system for optimizing brain stimulation therapy in Parkinson's disease and essential tremor patients.
Work Experience
Technical Co-founder
Antler
- Focused on formal definitions of business and financial models, including investment thesis and estimation of revenue and profit.
- Deployed a proof of concept to forecast streaming revenue for music artists using multi-modal input data.
- Raised a pre-seed investment round with Antler VC as a co-founder of the idea.
- Developed a tech vision and roadmap, including a hiring plan.
Machine Learning Engineer (via Toptal)
Global Food and Beverage Corporation
- Set up and rolled out an existing media mix model for a new geographical market and product family as a member of an MLOps team.
- Designed, implemented, and deployed a POC for a media mix model based on Bayesian statistical modeling as a member of an ML R&D team.
- Led a team of five ML engineers and data scientists. The team developed, benchmarked, productized, and deployed a next-generation media mix model for a marketing team.
- Designed, implemented, and deployed global marketing budget allocation across the entire portfolio of the organization.
Technical Co-founder
Entrepreneur First
- Co-founded a company that develops a knowledge management framework for IT teams.
- Developed and implemented a system for analyzing multi-domain corpora using transformer-based NLP models.
- Designed and deployed AWS infrastructure to service a neural search engine.
Consultant
D-fine
- Validated credit risk and accounting models in a large German bank.
- Performed predictive and prescriptive statistical analysis of soccer players' data for injury prediction and talent development at a Bundesliga team.
- Deployed a data management system for a large European bank.
- Developed MLOps pipelines, including architecture optimization for neural networks, for an in-house project.
Doctoral Research Assistant
University of Freiburg
- Developed the first machine learning-based, closed-loop, deep brain stimulation system implemented in freely moving patients. The projects related to this achievement were carried out in close collaboration with clinicians and industry partners.
- Established data-driven adaptive deep brain stimulation as a novel research field in the university.
- Published seven research articles in peer-reviewed scientific journals and 10+ contributions to scientific workshops and conferences in the fields of machine learning, data science, and neuroscience.
- Supported the machine learning lecture of the Master in Computer Science program for five years with the conception of exercises and exams and tutoring. The average attendance of the lecture was around 100 students per semester.
- Supervised a team of 2-5 (paid) master's research assistants in their supporting tasks at the lab.
- Supervised 15+ students in their master's and bachelor's theses in the research lab.
Research Assistant
National University of Colombia
- Taught a course on analog electronics as the sole lecturer. In addition to preparing lectures, exercises sheets, and exams, I supervised the execution of student's projects.
- Supervised one (paid) undergraduate teaching assistant for the lecture on analog electronics.
- Developed new methods for source localization of neural signals, resulting in a scientific publication in a peer-reviewed journal.
Experience
Research Discovery Engine Based on NLP Methods
Key Activities
• Implemented a PoC system consisting of a discovery engine for machine learning research using large language models.
• Designed and deployed cloud infrastructure serving the discovery engine.
• Created a business model and go-to-market strategy.
• Conducted user discovery and development interviews with more than 50 interviewees.
Media Mix Model for Consumer Products
Key Activities
• Implemented a learning model based on state-of-the-art research papers.
• Customized the model based on specific properties of the data available.
• Deployed the model to the cloud to be used by the MLOps team.
• Improved the model iteratively using feedback from the business unit.
• Presented results to several non-technical stakeholders in the business unit.
ML-based Adaptive Deep Brain Stimulation System for Essential Tremor Patients
https://www.frontiersin.org/articles/10.3389/fnhum.2020.541625/fullKey Activities
• Established the cooperation between our research lab at the University of Freiburg (brain state decoding lab) and the University of Washington (biorobotics lab).
• Conceived and developed the underlying machine learning, control, and digital signal processing methods.
• Deployed the algorithms on a host PC and the embedded system of the patients' neurostimulators.
• Executed the data collection experiments.
• Performed offline analysis of the collected data.
• Wrote and edited the final manuscript for a peer-reviewed publication.
Data Analysis of Injury Data in a Soccer Team
Key Activities
• Prepared and cleaned the data from several databases.
• Conducted descriptive and prescriptive analyses of the data.
• Presented the results to all stakeholders, including non-technical personnel.
Deployment of a Data Management System
Key Activities
• Configured and deployed UAT and production environments.
• Implemented a CI/CD pipeline for the back and front end.
Decoding Parkinson's Disease Symptoms from Brain Signals
https://www.sciencedirect.com/science/article/pii/S2213158220302138Key Activities
• Designed and executed the data collection experiments.
• Preprocessed data and performed exploratory data analysis.
• Conceived and implemented the novel ML method.
• Validated the novel ML method with the collected data and a benchmark against state-of-the-art models, including deep convolutional neural networks.
• Applied AutoML for hyperparameter optimization of all considered models.
• Wrote and edited the final manuscript published in a peer-reviewed journal.
Data Augmentation Framework for ML in Neuroscience
https://www.frontiersin.org/articles/10.3389/fninf.2019.00055/fullWe tackled the following challenges:
• Scarcity of data available when using data-driven methods in the analysis of brain signals.
• Unreliability of the available labels
• High level of noise in the raw signals.
Key Activities
• Conceived the idea.
• Executed the data analysis.
• Wrote the scientific manuscript published in a peer-reviewed journal.
ML-based Optimization of Marketing Budget Allocation
Automation of Artist & Repertoire for a Music Label
https://popp.land/The proof of concept was developed in the context of Antler, a pre-idea startup accelerator. With the POC and the developed business plan, we raised $100,000 in pre-seed funding.
Education
PhD in Computer Science
University of Freiburg - Freiburg, Germany
Master's Degree in Engineering
National University of Colombia - Manizales, Colombia
Engineer's Degree in Electronics Engineering
National University of Colombia - Manizales, Colombia
Skills
Libraries/APIs
Scikit-learn, Matplotlib, Pandas, NumPy, PyTorch, OpenCV, React, TensorFlow
Tools
Spyder, MATLAB, Git, Seaborn, Jupyter, AutoML, PyCharm, Excel 2010, AWS CloudFormation
Languages
Python, SQL, R, Java, C#, JavaScript
Paradigms
Anomaly Detection, User Acceptance Testing (UAT), Agile Project Management
Platforms
Windows, Linux, Jupyter Notebook, Docker, Amazon Web Services (AWS), JBoss EAP, Visual Studio Code (VS Code), MacOS
Storage
Database Management Systems (DBMS)
Other
Digital Signal Processing, Programming, Time Series Analysis, Linear Algebra, Machine Learning, Neuroscience, Deep Learning, Data Science, Research, Technical Writing, Statistics, Statistical Methods, Data Science, Data Analysis, Data Engineering, Neural Networks, Statistical Modeling, Predictive Analytics, Writing & Editing, Statistical Analysis, Artificial Intelligence (AI), Consulting, Classification Algorithms, Generative Pre-trained Transformers (GPT), APIs, Mathematics, Probability Theory, Reinforcement Learning, Bayesian Statistics, Algorithms, Electronics, Natural Language Processing (NLP), OpenAI, Text Processing, Generative Artificial Intelligence (GenAI), Retrieval-augmented Generation (RAG), Open-source LLMs, CTO, Full-stack, Finance, Computer Vision, Image Processing, Circuit Design, Control Theory, Calculus, Machine Learning Operations (MLOps), Data Warehousing, CI/CD Pipelines, Generative Systems, Large Language Models (LLMs), Business Planning, IT Project Management, Natural Language Understanding (NLU), Customer Research, Forecasting, Business Modeling, Business Model Canvas, Financials, Financial Data, Multimodal Models, FastAPI, Cloud Infrastructure, Marketing Analytics, Marketing Attribution, Marketing Mix, Front-end, Back-end, Pitch Decks, cursor
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