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Sergiy Onenko, Full-stack Web Developer in Lviv, Lviv Oblast, Ukraine
Sergiy Onenko

Full-stack Web Developer in Lviv, Lviv Oblast, Ukraine

Member since May 22, 2019
Sergiy is a highly skilled full-stack developer who has worked at companies like CityBlock NewMotion (ShellCharge) and Samsung. He has built his skills at Europe's largest charge network for electric cars. Sergiy has created many apps from scratch, improved existing mature projects, and participated in many startups, three of which are thriving!
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Portfolio

  • Toptal Projects
    Chrome, React, Sketch, Figma, PostgreSQL, Node.js, Express.js, Ionic, Angular...
  • NewFirePartners
    Node.js, Webpack, Angular, AngularJS, TypeScript, ECMAScript (ES6)...
  • Pubium
    Docker, React, Silhouette, Slick, PostgreSQL, MongoDB, Node.js...

Experience

Location

Lviv, Lviv Oblast, Ukraine

Availability

Part-time

Preferred Environment

Visual Studio Code, Git, OS X, Scrum, React, Next.js, Solidity, GraphQL, PostgreSQL, Notion

The most amazing...

...experience I've had was working at a successful startup from the beginning in the role of the key developer and lead.

Employment

  • Freelance Developer

    2019 - PRESENT
    Toptal Projects
    • Created the skeleton for a complex TypeScript/React chrome extension and built a great development team who took the extension to the next level, also porting it to mobile platforms.
    • Created the functional design for a cross-platform application "startup in stealth mode."
    • Configured an AWS deployment process, EC2, Bash Script, PostgreSQL, and SSL.
    • Collected requirements for every next feature set and made demos and standups.
    • Implemented the actual application, including authentication (Google and email), authorization, file upload, messaging, and user management.
    Technologies: Chrome, React, Sketch, Figma, PostgreSQL, Node.js, Express.js, Ionic, Angular, Web Development, REST APIs, JavaScript, SQL, Bootstrap, TypeScript, Git, Protractor, Karma, Sass, RxJS, Chrome Extensions, Scrum, iOS, Docker, MongoDB, Bash, Amazon Web Services (AWS), Xcode, CSS3, HTML5, Data Visualization, Maps, JSON Web Tokens (JWT), Integration Testing, Testing, Unit Testing, Webpack, Functional Programming, Ionic 4, OOP Designs, WebSockets, Coaching, Leadership, Safari Extensions, Kanban, WatchOS, Architecture, Domain-driven Design (DDD), OS X, Visual Studio Code, ECMAScript (ES6), Bcrypt, Flutter, React Native, CSS, GraphQL, Python

  • Technical Lead

    2017 - 2019
    NewFirePartners
    • Designed and developed the micro frontend architecture for the existing Angular 5 app.
    • Created a better development process and introduced new build commands that allow switching between development environments without needing to dig tons of documentation.
    • Improved all team (30+ developers) development speed by reducing application build time in development mode five times.
    • Created and contributed to the core library used across all pluggable applications.
    • Shared knowledge with the team and distributed teams.
    Technologies: Node.js, Webpack, Angular, AngularJS, TypeScript, ECMAScript (ES6), JavaScript, Web Development, REST APIs, Bootstrap, Git, Protractor, Karma, Sass, Chart.js, RxJS, Scrum, Meteor, Bash, Jira, IntelliJ IDEA, Integration Testing, Testing, Unit Testing, Dependency Injection, E2E Testing, Functional Programming, Google Chart API, OOP Designs, WebSockets, Coaching, Leadership, Safari Extensions, Architecture, Domain-driven Design (DDD), OS X, IntelliJ, Visual Studio Code, CSS

  • Co-founder and Architect

    2017 - 2018
    Pubium
    • Designed and developed an application from scratch, including delegation to other developers. Fully controlled step-by-step implementation, introducing the Scrum process.
    • Created the back end for the management portal, including the roles system.
    • Designed the restaurant portal's front-end development for other developers, allowing them to register restaurants and manage tables, days, hours, and reservations.
    • Designed and implemented POC for the RESTfull back-end app.
    • Created the notifications application for push notifications across all existing infrastructure.
    • Set up all development and production environment,s including Docker and Swarm.
    • Integrated the application with socials and mail services.
    • Coached and translated the most important knowledge to the team.
    Technologies: Docker, React, Silhouette, Slick, PostgreSQL, MongoDB, Node.js, Play Framework, Scala, Web Development, REST APIs, SQL, Bootstrap, TypeScript, Algorithms, Git, Express.js, Google Maps, Sass, Scrum, Arduino, Raspberry Pi, Realm, Bash, C++, CSS3, HTML5, IntelliJ IDEA, Akka Actors, Dependency Injection, Akka Streams, Webpack, Functional Programming, OOP Designs, WebSockets, Coaching, Leadership, SBT, Kanban, Docker Swarm, WatchOS, Architecture, Domain-driven Design (DDD), OS X, IntelliJ, ECMAScript (ES6), CSS

  • Senior Web Developer

    2015 - 2016
    IDMC
    • Architected and developed the front end for web-based healthcare applications from scratch.
    • Designed and developed the REST layer for the application.
    • Added complex role, permission, and restriction system for users.
    • Developed Elasticsearch-based aggregations and translated them to visualizations and tables.
    • Created complex filters system using tables and charts.
    • Contributed to Kibana, where we needed additional features.
    • Implemented a system that alerts if microorganisms evolved resistance to certain antibiotics.
    Technologies: React, AmCharts, AngularJS, ScalaTest, Elasticsearch, PostgreSQL, Akka HTTP, Scala, Web Development, REST APIs, JavaScript, Bootstrap, Algorithms, Git, Google Maps, Sass, Chart.js, Scrum, Bash, Jira, CSS, CSS3, Akka, Data Visualization, Maps, IntelliJ IDEA, Akka Actors, Akka Persistence, Dependency Injection, Akka Streams, LeafletJS, Functional Programming, Apache Camel, Google Chart API, OOP Designs, WebSockets, Leadership, HL7, SBT, Kibana, Kanban, Gulp, Bower, HL7 FHIR Standard, Architecture, Domain-driven Design (DDD), OS X, IntelliJ

  • Software Developer

    2012 - 2015
    NewMotion
    • Designed and developed of RESTfull application that allows integrating partners to our services.
    • Contributed to the main web application - https://my.newmotion.com/ it allows users to manage their charge points, shows currently available charge points on the map, manages subscription plans, etc.
    • Contributed to core application that actually manages charging points behavior.
    • Contributed to the application that calculated payments charge point usage.
    Technologies: MySQL, Lift, Kendo UI, HAL, Akka, PostgreSQL, Slick, spray, CSS, AngularJS, Scala, Web Development, REST APIs, JavaScript, SQL, Bootstrap, jQuery, Algorithms, Git, Google Maps, Less, Scrum, Bash, Linux, Jira, Data Visualization, Maps, IntelliJ IDEA, Akka Actors, Akka Persistence, Integration Testing, Testing, Unit Testing, Dependency Injection, E2E Testing, LeafletJS, Functional Programming, OOP Designs, Regression Testing, SBT, Kanban, RabbitMQ, Architecture, Domain-driven Design (DDD), OS X, IntelliJ

  • Lead JavaScript Developer

    2011 - 2012
    Samsung R&D Ukraine
    • Designed and developed JavaScript/HTML5/CSS3 mobile UI library for RIA in e-Book Framework. The framework itself was integrated with C#.
    • Designed a web-based application for creating animation scenes.
    • Led team of seven developers.
    • Extended internal libraries for Tizen.
    • Supported Kies Air mobile app. Added more screen resolutions, more devices, and more abilities (e.g. preview photos).
    Technologies: NetBeans, Subversion (SVN), HTML5, CSS3, PHP, JavaScript, Web Development, REST APIs, jQuery, Git, C++, C, Linux, Data Visualization, Dependency Injection, OOP Designs

  • Lead Web Developer

    2011 - 2011
    OS-Direct
    • Designed and developed a web-based internal application that allows managing team using regular reports from team members. Application is capable to: photo upload, data entry, generate web-based reports including charts, download PDF reports. Many different users used that app so I added complex roles system.
    • Made web base application for live streaming of conferences with pre-moderated chat with advanced roles system.
    • Created data analysis app that visualized requested data with advanced filtering and grouping.
    • Created landing pages for customers.
    Technologies: CSS, HTML, MySQL, PHP, MODx, Ext JS, Web Development, REST APIs, JavaScript, SQL, jQuery, Data Visualization, Dependency Injection, OOP Designs

  • Web Developer

    2010 - 2011
    Freelance
    • Created a custom website for a photographer with abilities to manage pictures and add watermarks to that.
    • Created web-based application for teachers, It allows to create courses, post articles, add tests, and attach videos.
    • Created a tool for students that allows to pass courses, pass exams, print course contents, and tests.
    • Made back end for vacation tracker.
    Technologies: CSS, HTML, MySQL, PHP, JavaScript, Ext JS, Web Development, SQL, jQuery, Data Visualization, Dependency Injection

Experience

  • NewMotion
    https://my.newmotion.com

    NewMotion or Shell Recharge Solutions. Initially, I was a front-end developer; during the project, I became a full-stack developer for the most prominent app in the company. In the end, I was focused on the back end exclusively, and I was in charge of the newly created microservice using Scala and Akka.

Skills

  • Languages

    CSS3, HTML5, JavaScript, TypeScript, Scala, SQL, CSS, Sass, Less, ECMAScript (ES6), Bash, C++, C, PHP, GraphQL, Python, Solidity, Swift

  • Frameworks

    Angular, JSON Web Tokens (JWT), Bootstrap, Express.js, Ionic, Play 2, AngularJS, Protractor, Apache Camel, Ionic 4, Next.js, Ext JS, Play Framework, Akka, Kendo UI, Lift, Chrome, Flutter, React Native

  • Libraries/APIs

    REST APIs, jQuery, React, Chart.js, Node.js, Google Chart API, Akka Streams, LeafletJS, Google Maps, RxJS, Babylon.js, Slick, spray

  • Tools

    IntelliJ IDEA, Git, ScalaTest, Karma, Webpack, YouTrack, Knex.js, Jira, IntelliJ, Xcode, Subversion (SVN), Figma, Sketch, Gulp, RabbitMQ, Bower, Canvas 2D, SBT, Kibana, Docker Swarm, Notion

  • Platforms

    Godot, Visual Studio Code, OS X, Linux, NetBeans, MODx, Amazon Web Services (AWS), Arduino, Raspberry Pi, WatchOS, iOS, Docker, Meteor, DigitalOcean

  • Storage

    PostgreSQL, Elasticsearch, MySQL, MongoDB, Realm

  • Other

    Web Development, AmCharts, Data Visualization, Maps, Chrome Extensions, Front-end, Algorithms, Akka Actors, Akka Persistence, Integration Testing, Safari Extensions, Architecture, Non-fungible Tokens (NFT), ClickUp, Silhouette, HAL, Akka HTTP, Regression Testing, Machine Learning, Coaching, Leadership, OOP Designs, HL7, WebSockets, Domain-driven Design (DDD), Crypto, Bcrypt

  • Paradigms

    Dependency Injection, Testing, Unit Testing, E2E Testing, Functional Programming, Scrum, Kanban, HL7 FHIR Standard

Certifications

  • Hacking with WatchOS 4
    DECEMBER 2018 - PRESENT
    Udemy
  • Complete Sketch 5 Course
    NOVEMBER 2018 - PRESENT
    Udemy
  • The Complete iOS Bootcamp Development
    NOVEMBER 2018 - PRESENT
    Udemy
  • Principles of Reactive Programming
    JANUARY 2014 - PRESENT
    Coursera
  • Functional Programming Principles in Scala
    JUNE 2013 - PRESENT
    Coursera

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