Full-stack Software Developer in Larnaca, Cyprus
Software Engineer2016 - PRESENTSeven13
- Built web hook integration between Tilda.cc and ActiveCampaign and helped to create various marketing automatizations and coded responsive email templates.
- Developed a complete solution to generate content and convert it to PDF documents using Headless Chrome Browser.
- Created a sports news delivery service via Messenger and Telegram chat bots. This allowed us to deliver important news in real time to bookmakers and people who make bets.
Front-end Web Developer2016 - 2017Lifetime Fitness
- Built a new version of Athlinks' website using React.
- Implemented a variety of cross-platform responsive components.
- Revised and refactored the existing codebase.
Software Engineer2015 - 20162PVentures
Technologies: GAE, Google BigQuery, ElasticSearch, AWS, RedShift, Node.js, AngularJS, React.js
- Deployed resilient ElasticSearch clusters to AWS Beanstalk.
- Designed and created cross-platform analytics tracking script similar to Google Analytics. Built large set of tests and configured Webdriver.io to run those tests in variety of different environments.
- Wrote an Async event pipeline which received data from the client-side tracking script, filtered and then enriched it with additional data, and finally saved it in BigQuery.
- Wrote a reports generator API for BigQuery. Created a lot of complex analytical queries for BQ.
- Built an analytics dashboard for C-level executives.
- Implemented a service to create and renew membership subscriptions.
- Managed a huge data set of existing tracking data. Had to export, transform, filter, and enrich it with other data before finally migrating it to BQ. Had to write dozens of data validation queries.
- Managed continuous implementation and deployment via Jenkins.
Web Developer2015 - 2015Fubo.tv (via Toptal)
Technologies: Node.js, MongoDB
- Found and fixed memory leaks in Node.js applications.
- Rebuilt the current API to allow hundreds of thousands of requests to be processed.
- Improved database schema and indexing.
- Maintained CD and server.
- Made performance improvements.
Web Developer2015 - 2015MyTravelCharter, LLC (via Toptal)
Technologies: Node.js, AngularJS, MongoDB, PostgreSQL
- Implemented a variety of UI components and APIs.
- Designed and deployed a booking system with transaction support for MongoDB.
- Made performance improvements and updates.
- Created an API to make complex reports simple.
- Maintained server deployments, CD, and firewalls.
Senior Scala Developer2012 - 2015Meta Labs, Inc.
Technologies: Scala, Java, Node.js, MATLAB, Machine Learning
- Developed several simple eCommerce stores using Magento.
- Created a handwriting recognition neural network.
- Hacked a Ukrainian bank during a bug bounty program.
- Improved a marketing and transaction email platform actively, raising it to the standards comparable to Mandrill.
- Implemented custom integrations with Chase PaymentTech and First Data Compass.
- Developed software to read mag stripe data using square readers.
Software Developer2012 - 2013HyperMail, Inc.
Technologies: PHP, Node.js, Scala, Cassandra, Redis
- Developed a platform to track and submit marketing emails.
- Designed and deployed a successful payment gateway for high-risk businesses in India.
- Created a resilient Cassandra cluster to hold and analyze a billion customer contact records.
- Created a custom merchant risk rate index based on a short-term transactions record log and publicly available information.
- Built a data exchange platform.
- Created an affiliate tracking system using PHP and PostgreSQL. Created a coupon management system and integrated it with the affiliation.
PHP Developer2011 - 2012Carousel Checks
- Supported an eCommerce store.
- Developed a blogging engine.
- Implemented an integration with Google Wallet.
- Hunted down numerous security vulnerabilities.
- Managed Magento migrations.
- Payment Gateway (Development)
Payment Gateway is a software providing single API for payment processing via multiple merchant backends. Has integrations with Chase PaymentTech, FirstData Compass, FirstData Nova and various offshore providers. This software includes different algorithms and techniques to spot a fraudulent activity.
- Exploring Supervised Machine Learning Algorithms (Publication)While machine learning sounds highly technical, an introduction to the statistical methods involved quickly brings it within reach. In this article, Toptal Freelance Software Engineer Vladyslav Millier explores basic supervised machine learning algorithms and scikit-learn, using them to predict survival rates for Titanic passengers.
- Debugging Memory Leaks in Node.js Applications (Publication)Memory leaks in long running Node.js applications are like ticking time bombs that, if left unchecked in production environments, can result in devastating outcomes. These bugs are often considered to be hard to find. However, with the right tools and a strategic approach, memory leaks can not only be solved but also avoided in the future. In this article, Toptal engineer Vladyslav Millier gives us insight into what memory leaks are, how some sophisticated debugging tools can be used to find memory leaks, and how to plug them once and for all.
- Vlad is a mentor in the Toptal Global Mentor’s Program. This program is a partnership between Toptal and General Assembly to provide high quality mentorship for students from minority and low income backgrounds who are looking to begin their careers as professional software engineers. Vlad shows commitment to diversity in tech by mentoring a General Assembly student every week for a year, covering everything from coding tips and tricks to advice on making it in the industry.
FrameworksFlux, Redux, Express.js, Ruby on Rails (RoR), AngularJS, Zend Framework, Akka 2, Play Framework
Libraries/APIsReact, Node.js, Stripe API, Facebook API, Stripe, jQuery, Highcharts, spray, VK API
ParadigmsREST, Parallel & Distributed Computing, Agile Software Development
PlatformsMacOS, Ubuntu, Linux, Heroku, CentOS
StorageMariaDB, MySQL, InnoDB, Redis, PostgreSQL, Cassandra, MongoDB, CouchDB, Couchbase
ToolsGulp.js, Photoshop CC, Grunt.js, Mongoose, Webpack 2, Grunt, Webpack, Vim Text Editor, Terminal, Tortoise Git, Adobe Photoshop, MATLAB, IntelliJ IDEA
OtherChase Paymentech, FirstData, Omise