Scroll To View More
Hire the top 3% of freelance developers
toptal.com
Call us: +1.888.604.3188
Andrii Kostenko, Perl Developer in Helsinki, Finland
Andrii Kostenko

Perl Developer in Helsinki, Finland

Member since May 22, 2013
Andrii is an accomplished software engineer experienced in creating large-scale, complex applications. He has worked both as a back-end and front-end engineer. He excels at planning and implementing intricate solutions to technical problems, including determining which technologies should be used.
Andrii is now available for hire
Hire Andrii

Portfolio

Experience

  • Linux, 7 years
  • Perl, 5 years
  • SQL, 5 years
  • PostgreSQL, 3 years
  • Python, 3 years
Helsinki, Finland

Availability

Part-time

Preferred Environment

PyCharm, Git, Mac OS, Vim

The most amazing...

...thing I've coded is an online commenting engine that handles millions of visitors per day.

Employment

  • Software Engineer

    2014 - 2016
    HealthJoy
    • Gained knowledge of the American health insurance system.
    • Contributed to the composition of up to 70% of the project's test coverage.
    • Tried several XMPP solutions and created a high-load solution with ejabberd.
    • Wrote a Cron-like daemon for RQ.
    • Collaborated with team members in an Agile/Scrum environment, which increased productivity.
    • Improved ability to communicate with clients in English.
    • Created docker-based development environment, which allows new and current developers quickly setup required project infrastructure.
    Technologies: Python, Flask, RQ, AngularJS

  • Entepreneur

    2010 - 2014
    Visamap
    • Created a custom world map using MapServer.
    • Created a number of fetchers from different sources.
    Technologies: Python, GeoDjango

  • CTO

    2013 - 2013
    Skiliks
    • Converted a prototype with write-only code to a production-ready project, including working architecture and unit-tests (PHPUnit and Buster.JS)
    • Switched development to a Scrum-like process.
    • Founded a team of qualified software/QA engineers in Kyiv, Ukraine.
    • Replaced buggy code (built over two month of development) with a remote API of existing services.
    • Refactored and rewrote numerous project parts.
    • Covered code with JS/PHPUnit tests (over 180 tests created).
    • Administrated development/production servers.
    Technologies: PHP, Yii, JavaScript, Backbone.js

  • Software Engineer

    2012 - 2013
    Mybook
    • Chose the programming language and technology package for the company (Python/Django 1.4/Celery).
    • Created a CI environment with 1100 passing tests (tests were mostly for used applications)
    • Used a variety of public modules instead of writing redundant code, patching them if needed.
    • Created a large project with an efficient, clean code structure.
    • Created numerous bugreports in Django bugtracker with patches.
    • Developed a public API with Django Tastypie.
    • Improved Django Coffin so that it worked as a transparent template loader.
    Technologies: Python, Django, Celery, Jinja2

  • Software Engineer

    2011 - 2011
    Kinohod
    • Refactored a complex body of code, making it more supportable.
    • Created a cell phone website version of the code using jQuery Mobile.
    Technologies: Perl, Catalyst, jQuery Mobile

  • Software Engineer

    2009 - 2011
    Rambler-Afisha Internet Holding
    • Developed highly-scalable internet applications
    • Optimized a database for high load processing.
    • Refactored a service handling over 10 million requests per day.
    • Improved the libpurple library to support a large number of accounts.
    • Improved the speed and code quality of existing code.
    Technologies: Perl, Catalyst, C++, node.js, PL/pgSQL, PHP

  • Software Engineer

    2007 - 2009
    Privatbank
    • Created a peer-to-peer money transfer application.
    • Developed a service to take 25 web site screenshots per second.
    • Created a sandbox for using compilers with online IDEs.
    • Used a partial MySQL master-master replication to create two interfaces: one was public with public data and one was private in a bank network with private data.
    • Created a complex administrator panel for payment transaction monitoring.
    Technologies: Perl, Lua, C#

Experience

  • Visamap (Development)

    An online visa requirement database.

  • MyBook Online Library (Development)
    http://mybook.ru/

    This is my most interesting and successful project. It includes highly readable code, test coverage, and effective technologies.

  • Walk2web (Development)

    A project that creates a tree from incoming and outgoing links.

  • Kinohod (Development)
    http://kinohod.ru

    A Russian ticket selling company.

  • Credit Card Number Generator (Development)

    A simple valid credit card generator on GAE.

  • Skiliks (Development)

    An online management assessment tool.

  • Healthjoy (Development)
    http://healthjoy.com

    Concierge service for US health insurance

Skills

  • Languages

    Perl, Python, SQL, JavaScript, CSS3, HTML5, PHP, C++, C

  • Frameworks

    Django, Flask, Catalyst, AngularJS, Yii

  • Storage

    PostgreSQL, MySQL, Memcached, Redis, AWS RDS, AWS S3, AWS DynamoDB, PostGIS, Kyoto tycoon

  • Libraries/APIs

    SQLAlchemy, Python-rq, React, Node.js, DBIx::Class, jQuery, Backbone.js

  • Tools

    Vim Text Editor, Nginx, Git, Ansible, Sequelize, Chef, Celery, AWS ECS, Zsh

  • Paradigms

    Test Automation, Scrum, Agile Software Development, Test-driven Development (TDD)

  • Platforms

    Docker, Linux, FreeBSD, AWS EC2, MacOS

  • Other

    XMPP, OAuth

Education

  • Partially completed degree in Appiled Mathematics
    2006 - 2008
    Dnipropetrovsk National University - Dnipropetrovsk, Ukraine
  • Graduate degree in Software Engineering
    2004 - 2006
    IT Academy "Step" - Dnipropetrovsk
Hire the top 3% of freelance developers
toptal.com
Call us: +1.888.604.3188
To view more profiles, join ToptalJoin Toptal
I really like this profile
Share it with others