Oleksii Sliusarenko
Verified Expert in Engineering
Algorithms Developer
Kiev, Ukraine
Toptal member since November 4, 2019
Oleksii is a senior research engineer specializing in machine learning with several years of hands-on, in-depth experience. In his free time, he competes in international programming and math competitions—and often wins. At Deloitte and Grammarly, he developed their core deep learning and AI algorithms. Oleksii has worked at all stages of R&D from problem formulation with clients to product deployment.
Portfolio
Experience
- Algorithms - 10 years
- Machine Learning - 8 years
- Data Science - 8 years
- Generative Pre-trained Transformers (GPT) - 7 years
- Natural Language Processing (NLP) - 7 years
- Scikit-learn - 6 years
- Deep Learning - 5 years
- Python - 5 years
Preferred Environment
Machine Learning, Deep Learning, Natural Language Processing (NLP), Generative Pre-trained Transformers (GPT), Data Science
The most amazing...
...thing I've created was a practical algorithm to solve an open AI problem: detecting English sentences that make no sense.
Work Experience
Senior Research Engineer (Machine Learning, NLP)
Abto Software
- Implemented a chatbot model designed for stable progressive learning for five years.
- Reimplemented part of Rasa chatbot framework to fix OOM error and make it production-ready.
- Found and fixed OOM error and experiment design problem in SoTA intent recognition paper.
Senior Research Engineer (Machine Learning, NLP)
Deloitte
- Implemented a contract classification algorithm with 95% accuracy which outperformed humans.
- Developed a complex text summarization algorithm with 80% accuracy.
- Created a company classification algorithm which increased human analytics quality by two times.
- Completed all stages of complex text summarization problem including framing the problem, annotating the data, creating the model, deploying and supporting.
- Organized data science hackathon which resulted in three new hires.
Research Engineer (Machine Learning, NLP)
Grammarly
- Developed a new sentence splitting component with 2X improvement in error rate.
- Built an auto-correct feature with 99% accuracy compared to 90% existing version.
- Implemented high-load storage with approximately 1,000,000 key-value requests per second per server.
- Reimplemented contextual spell checker with 10x speed-up.
- Implemented a practical solution with 99,9% specificity and 30% recall to an open problem of detecting sentences which don't make sense.
- Processed petabyte-scale internet dump using Apache Spark for creating n-gram language models.
- Prepared and conducted two courses on algorithms and data science.
- Increased part of speech tagger quality from 96% to 97%.
Analyst Engineer (Machine Learning)
UkrNet
- Developed an anti-spam system for an email provider that had tens of millions of users.
- Created a geo-tracking solution for ads which increased accuracy from 50% to 80%.
- Implemented Nginx plugin using C with 6000 geo-tracking requests per second per server.
- Built the back end for email IMAP protocol which enabled 100,000 users to use their favorite email clients.
Experience
AI-powered Writing Assistant
http://grammarly.comEducation
Master's Degree in Systems Analysis
National Technical University of Ukraine "Kyiv Polytechnic Institute" - Kyiv, Ukraine
Bachelor's Degree in Systems Analysis
National Technical University of Ukraine "Kyiv Polytechnic Institute" - Kyiv, Ukraine
Certifications
How to Start a Startup
Prometheus, Y Combinator
Intro to TensorFlow for Deep Learning
Udacity
Skills
Libraries/APIs
Scikit-learn, TensorFlow, Standard Template Library (STL), Matplotlib, NumPy, Pandas, OpenNLP, Keras, OpenCV, Natural Language Toolkit (NLTK), SpaCy
Tools
Apache OpenNLP, Jupyter, Weka, Rasa.ai, Boto
Languages
Python, Java, C++, Bash
Frameworks
Spark, Hadoop, Flask, Boost, Spring
Storage
MySQL, PostgreSQL, MongoDB
Platforms
Docker, Amazon Web Services (AWS), Azure
Other
Data Science, Natural Language Processing (NLP), Algorithms, Machine Learning, Classification Algorithms, Data Analysis, Generative Pre-trained Transformers (GPT), Deep Learning, Data Cleaning, Data Visualization, Time Series, Chatbots
How to Work with Toptal
Toptal matches you directly with global industry experts from our network in hours—not weeks or months.
Share your needs
Choose your talent
Start your risk-free talent trial
Top talent is in high demand.
Start hiring