Iaroslav Sobolev, Software Developer in Berlin, Germany
Iaroslav Sobolev

Software Developer in Berlin, Germany

Member since March 29, 2018
Iaroslav is a professional software engineer who's especially passionate about JavaScript and complex web user interfaces and services. With years of hands-on experience, he has been building web applications and services that also high-load projects, converting complex tasks and engineering problems into software solutions.
Iaroslav is now available for hire


  • Expand.org (via Toptal)
    Object-oriented Design (OOD), Redux-Saga, Stylus, Babel...
  • Leverton
    Object-oriented Design (OOD), Babel, GitLab, Agile Software Development...
  • Reflexia
    Object-oriented Design (OOD), Redux-Saga, Babel, Agile Software Development...



Berlin, Germany



Preferred Environment

Docker, Figma, Sketch, Git, Visual Studio Code, VS Code, MacOS

The most amazing...

...project I've worked on recently is a platform for AI-based data analysis and visualization.


  • Lead Front-end Engineer

    2018 - 2020
    Expand.org (via Toptal)
    • Developed a front-end application allowing Expand.org clients to execute micro-tasks.
    • Built from scratch a task management application for requesters from the planning and design stages to the launch.
    • Developed and open-sourced a React-based UI component library and UIkit used across all company UIs.
    • Constructed a generic form library and visual editor for building microtask UIs.
    Technologies: Object-oriented Design (OOD), Redux-Saga, Stylus, Babel, Agile Software Development, Microservices, REST APIs, CSS, Front-end, Jest, Web3.js, Google Cloud, Go, Node.js, Docker, PostCSS, Webpack, Redux, React
  • Senior Front-end Engineer

    2017 - 2018
    • Developed public-facing instruments for managing access to the SaaS platform.
    • Created and maintained several libraries used across the company for building scalable front-end applications.
    • Reworked the company's component library (React components) with Lerna and Storybooks.
    Technologies: Object-oriented Design (OOD), Babel, GitLab, Agile Software Development, Microservices, REST APIs, CSS, Front-end, TypeScript, Jest, Storybook, Zeplin, Node.js, Docker, PostCSS, Webpack, Redux-Saga, Redux, React
  • Lead Front-end Developer (Contract)

    2016 - 2018
    • Designed and implemented from scratch the front end platform for complex data visualization with React and D3.js.
    • Developed a framework for real-time user notifications.
    • Built applications for marking relationships in data (building an ontology) and representing these relationships in the form of a graph.
    • Created the front end for invoice management application with complex search, filtering, and tagging capacities.
    • Designed and Implemented BFF API layer.
    • Worked closely with other team members to understand product requirements and translate them into software designs and code.
    Technologies: Object-oriented Design (OOD), Redux-Saga, Babel, Agile Software Development, Microservices, REST APIs, CSS, Front-end, Jest, Express.js, Apache Kafka, Zeplin, Redis, Node.js, Docker, Stylus, D3.js, Sagas, Redux, React
  • Front-end Team Lead

    2014 - 2017
    • Designed and implemented a framework for building scalable front-end applications.
    • Improved the front-end development process, developed coding guidelines, and established the use of code quality tools (linting, testing).
    • Managed the front-end team which involved project estimating and planning and code reviews.
    • Developed a web-based mobile application for students and teachers.
    Technologies: Object-oriented Design (OOD), Redux-Saga, Babel, Agile Software Development, Microservices, Microsoft Visual Studio, REST APIs, .NET, Front-end, TypeScript, Jest, Express.js, C#, ASP.NET MVC, CSS, Selenium, Webpack, React, Node.js, JavaScript
  • Senior Software Engineer

    2011 - 2014
    • Migrated a monolithic ASP.NET application to new a service-oriented architecture on top of the ASP.NET MVC framework.
    • Set up the platform for UI testing that could run multiple tests in parallel (Selenium, Selenium Grid, Watir, Cucumber, and Ruby).
    • Designed the architecture core services written on C# and Node.js.
    • Developed a tool for deployment in a distributed environment—it allowed the reduction of downtime during the releases and multiple deployments a day in every environment.
    Technologies: Object-oriented Design (OOD), Agile Software Development, Microsoft Visual Studio, REST APIs, .NET, Cucumber, Redis, Watir, Ruby, Selenium Grid, Backbone.js, T-SQL, Entity Framework, ASP.NET MVC, Node.js, C#
  • Software Engineer

    2009 - 2011
    RBC Soft
    • Developed a platform for collecting and analyzing the results of the unified state exam.
    • Designed and implemented a collaboration platform which helped to set up communication between various government departments.
    • Reviewed peers' and junior developers' code.
    Technologies: Object-oriented Design (OOD), Microsoft Visual Studio, .NET, JavaScript, HTML, NHibernate, T-SQL, C#, ASP.NET MVC


  • Application for Managing Access to the SaaS Platform

    An application for managing the access rights of users and groups to various company products. Even inexperienced users can configure access rights with a high level of granularity.

  • Reflexia

    A complex structured-data visualization platform which allows to customers to extract insights from their data. It uses various techniques to represent data in the form of interactive graphs, diagrams, charts, and maps.

  • Web-based Tool for Describing Ontologies

    These are applications for marking relationships in data (building an ontology) and representing these relationships in the form of a visual graph on canvas. These relationships enable the analysis of user data using machine learning algorithms.

  • Mobile Web Application for Teachers and Students

    A web-based mobile application for teachers and students for Dnevnik.ru. It allows teachers to manage grades and homework and allows students to view their grades, homework, and schedules

  • Dnevnik.ru

    The number one site in Russia for school management, e-learning, and social networking. It solved many diverse problems within the whole development lifecycle.


  • Languages

    CSS3, C#, JavaScript, ES7, CSS, HTML, TypeScript, SCSS, GraphQL, Ruby, T-SQL, Go
  • Frameworks

    Redux, .NET, ASP.NET MVC, Express.js, Jest, React Native, Selenium, NHibernate, UIKit
  • Libraries/APIs

    React, Redux-Saga, Socket.IO, REST APIs, D3.js, Node.js, Selenium Grid, Entity Framework, Backbone.js, Web3.js
  • Tools

    Stylus, Atom, Slack, Microsoft Visual Studio, GitLab, TeamCity, Git, IntelliJ IDEA, PostCSS, Babel, VS Code, Cucumber, Watir, Zeplin, Vagrant, Sketch, Webpack, GitHub, Lerna, Figma
  • Paradigms

    Object-oriented Design (OOD), Test-driven Development (TDD), Microservices, Agile Software Development, Functional Programming
  • Other

    Front-end, Sagas, Storybook, Web Development
  • Platforms

    Docker, Amazon Web Services (AWS), MacOS, Apache Kafka, Visual Studio Code
  • Storage

    Redis, JSON, MongoDB, Google Cloud, MySQL


  • Master’s Degree in Applied Mathematics and Computer Science
    2003 - 2009
    Irkutsk State University - Irkutsk, Russia

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