toptal.com
Contact us: +1.888.604.3188
Kostas Familonidis, Software Developer in London, United Kingdom
Kostas Familonidis

Software Developer in London, United Kingdom

Member since November 21, 2013
Kostas is a passionate full-stack developer, most recently focused on cross-platform mobile app development but also experienced with a variety of other projects and platforms, from business process automation to finance and beyond.
Kostas is now available for hire
Hire Kostas

Portfolio

Experience

Location

London, United Kingdom

Availability

Part-time

Preferred Environment

Unix, Linux

The most amazing...

...thing I've developed is a CRM that integrates mail services in mobile devices.

Employment

  • Full-stack Web Developer

    2019 - PRESENT
    Procore Technologies, Inc.
    • Developed the application's stack to support internationalization across web platform.
    • Reviewed code and supported the team's internal QA (Quality Assurance) process.
    • Modernized existing parts of the application's codebase using the latest patterns.
    • Implemented TDD (Test Driven Development) and extensive acceptance-test coverage in-line with Agile development practices.
    Technologies: Functional Programming, Unix, Object-oriented Programming (OOP), HTML, Git, Redis, JavaScript, Ruby on Rails (RoR), Ruby, React

  • React Developer

    2016 - 2018
    Vertical Scope, Inc.
    • Developed cross-platform native mobile applications in iOS and Android using JavaScript and React Native.
    • Developed and integrated React components into a forum website using Redux architecture.
    • Improved UX (User Experience) and UI (User Interface) performance on mobile applications.
    • Implemented TDD (Test Driven Development) with Agile development practices.
    Technologies: Functional Programming, Unix, HTML, CSS, JavaScript, React Native, React

  • Full-stack Web Developer

    2017 - 2017
    Pivot.io, Inc.
    • Developed an application for automating business processes in Ruby, Ruby on Rails, JavaScript, and GraphQL.
    • Developed and integrated React components using Redux and sagas for concurrent data structures.
    • Transitioned REST (Representational State Transfer) APIs and micro-services in GraphQL implementations.
    Technologies: Unix, Object-oriented Programming (OOP), Git, GraphQL, React, Ruby on Rails (RoR), Ruby

  • Software Engineer

    2015 - 2015
    Sky UK, Ltd.
    • Developed full-stack applications using microservices in Ruby, Sinatra, and JavaScript.
    • Utilized A/B testing to validate product efficiency on customer retention rates.
    • Maintained and developed multiple custom rack middlewares in Ruby.
    • Implemented TDD (Test Driven Development) with Agile development practices..
    Technologies: Functional Programming, Unix, Object-oriented Design (OOD), Object-oriented Programming (OOP), Ubuntu, Rack, HTML, TeamCity, Git, SQL, Redis, jQuery, Sinatra, Ruby

  • Lead Developer

    2013 - 2015
    Ringley, Ltd.
    • Developed full-stack applications on the intranet/extranet deployed to the cloud.
    • Handled back-end system administration and infrastructure configuration to prepare for distributed computing.
    • Developed a contract management system for tracking job completion and staff performance.
    • Implemented and designed a back-end storage system for optimized performance in MongoDB and MySQL.
    • Implemented and designed an Elasticsearch cloud-based search engine solution.
    • Modernized existing Ruby on Rails applications by extracting business logic, using unit testing, and making use of JavaScript, Ruby, and Ruby on Rails engines.
    • Exposed secure web APIs to integrate with mobile applications.
    • Developed a financial application that monitors and calculates cash flows, payments fees, and percentage fees.
    • Restructured and introduced effective project management methodologies in the organization.
    Technologies: Functional Programming, Object-oriented Design (OOD), Ember.js, Unix, Ubuntu, GitLab, MongoDB, Sinatra, Elasticsearch, Redmine, HTML, Memcached, D3.js, Git, SQL, MySQL Daemon, Redis, jQuery, Red Hat Linux, CSS, JavaScript, Ruby on Rails (RoR), Ruby

  • Software Developer

    2013 - 2013
    Farncobe
    • Developed a back-end authentication system for a mobile application.
    • Integrated Facebook and Twitter API on the application UI.
    • Developed a full database-driven implementation for multi-language support.
    • Implemented TDD (Test Driven Development) and extensive acceptance-test coverage.
    Technologies: Object-oriented Design (OOD), Unix, PostgreSQL, Ubuntu, HTML, Git, SQL, Redis, Ruby on Rails (RoR), Ruby

  • PMO/Projects Coordinator

    2008 - 2012
    Intrasoft International
    • Oversaw SLA budgets.
    • Maintained the database backlog for tracking work in progress using Ruby, MySQL, and Linux.
    • Consolidated contracts and delivery of technical documents.
    • Produced and maintained all project documentation, including project plan and project scope.
    • Organized, prepared, and followed up the invoicing procedure, including infrastructure procurement and software license updates.
    Technologies: Linux, Redmine, OLAP, Git, MySQL Daemon, CSS, HTML, SQL, Ruby, Bash, Red Hat Linux

Experience

  • React and React Native (Development)

    Developed and enhanced user experiences on multiple forum sites utilizing React and React Native frameworks.

  • GraphQL Implementation (Development)

    Built a GraphQL implementation from scratch for utilizing very complex data structures and reporting statistics with minimum time delay.

Skills

  • Languages

    HTML, JavaScript, Ruby, HTML5, Bash, SQL, CSS, GraphQL

  • Frameworks

    React Native, Sinatra, Ruby on Rails (RoR), Ember.js

  • Libraries/APIs

    Mongoid, React, jQuery, Rack, D3.js

  • Tools

    Git, TeamCity, Redmine, GitLab

  • Paradigms

    Object-oriented Programming (OOP), Object-oriented Design (OOD), Functional Programming, Metaprogramming, OLAP

  • Platforms

    Linux, Ubuntu, Red Hat Linux, Unix

  • Storage

    Elasticsearch, Redis, MongoDB, MySQL Daemon, PostgreSQL, Memcached

Education

  • BSc degree in Business Administration (Technology)
    2000 - 2004
    University of Patras - Patras, Greece

Certifications

  • Red Hat Linux System Administrator
    SEPTEMBER 2012 - SEPTEMBER 2015
    Red Hat

To view more profiles

Join Toptal
Share it with others
Hire the top 3% of freelance developers TM