Ivan Nikolajev, Developer in Prague, Czech Republic
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Ivan Nikolajev

Verified Expert  in Engineering

Data Scientist and Developer

Prague, Czech Republic
Toptal Member Since
November 21, 2019

Ivan has experience working as a data scientist and a data engineer in network security and finance industries. This includes processing and cleaning data, formalizing business problems and creating solutions by designing features and applying machine learning techniques to solve the problems. Ivan works with big data using Spark and MapReduce, and can visualize and present results to stakeholders in an easy-to-understand format.


Freelance clients
Big Data, JavaScript, React, Scraping, Amazon Web Services (AWS), APIs, Python...
Scikit-learn, Python, Scala, Spark
Cisco Systems
Amazon Web Services (AWS), Scalding, Scala, Spark, Scikit-learn, Python, MATLAB




Preferred Environment

IntelliJ IDEA, Git, Spark, Scala, Python, Linux, MacOS

The most amazing...

...project I've worked on is a classifier that detected network endpoints infected by malware that performed cryptomining.

Work Experience

Full-stack Data Scientist

2020 - 2022
Freelance clients
  • Scraped data from many different sources and set up robust pipelines for regular data processing in AWS.
  • Built a system for providing regular reports based on various data sources; it is an entirely automatic cloud-based system.
  • Created internal websites for data monitoring and control.
Technologies: Big Data, JavaScript, React, Scraping, Amazon Web Services (AWS), APIs, Python, Pandas

Data Engineer and Data Scientist

2019 - 2020
  • Created an anomaly detection model that ran in Spark and provided anomalies for a transaction audit and visualization tool.
  • Worked on a data transfer project that spanned multiple departments and platforms and helped to safely transfer data within the company.
  • Designed and developed solutions for big data platforms.
Technologies: Scikit-learn, Python, Scala, Spark

Data Scientist

2013 - 2019
Cisco Systems
  • Created classifiers and anomaly detectors for catching malware in network traffic using metadata.
  • Performed data extraction and analysis, designed features, and built classification models using various machine learning techniques.
  • Worked with big data technologies on a daily basis, creating and optimizing a lot of complex analysis jobs in Spark that ran on large volumes of data.
  • Had to keep up with trends in machine learning and data science and implemented many state-of-the-art methods from scientific publications.
  • Drafted several US patterns on network security and machine learning. Many patents were successfully submitted, some already granted by the US Patent Authority.
  • Published commercial blogs and contributed to scientific papers.
Technologies: Amazon Web Services (AWS), Scalding, Scala, Spark, Scikit-learn, Python, MATLAB


2012 - 2013
Cognitive Security
  • Ran malware in sandboxed environments and gathered network telemetry.
  • Analyzed network telemetry from malware.
  • Designed detection algorithms for the malware based on the analysis.
Technologies: Wireshark, Java

Distributed Manipulation by Shaping Magnetic Field (MagMan Platform)

I participated in this project by measuring the responses of a metal ball to forces created by a magnetic coil. I used these measurements to create a model that was able to activate the coils to provide the required force on the object in real time. The model was based on numerical solver CPLEX by IBM.

This was implemented in Simulink and allowed real-time manipulation of the metal ball using a field of magnetic coil actuators.

A video was created based on this project that won the MATLAB and Simulink Student Design Challenge 2013.

2012 - 2014

Master's Degree in Cybernetics and Robotics, Systems and Control Specialization

Czech Technical University - Prague, Czech Republic

2009 - 2012

Bachelor's Degree in Cybernetics and Robotics, Systems and Control Specialization

Czech Technical University - Prague, Czech Republic


REST APIs, Scalding, Matplotlib, Scikit-learn, NumPy, PyTorch, React, Pandas


MATLAB, Git, Jupyter, IntelliJ IDEA, Wireshark, YourKit


Spark, Scrapy, Flask, Selenium


Python, JavaScript, HTML, Java, Scala, SQL, CSS, Julia, Bash, Simulink


PostgreSQL, MySQL, MongoDB


Data Science, ETL


Linux, Jupyter Notebook, Docker, MacOS, Amazon Web Services (AWS)


Algorithms, Big Data, Data Scraping, Scraping, Data Visualization, Data Analysis, Machine Learning, Web Scraping, Front-end, Full-stack Development, Cython, APIs

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