Oz Atacan, Developer in London, United Kingdom
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Oz Atacan

Verified Expert  in Engineering

Machine Learning Developer

London, United Kingdom
Toptal Member Since
February 15, 2016

Oz is a senior software engineer with over 12 years of experience developing high-quality software solutions for a variety of domains. He worked with small teams, startups, big corporations, and mid-sized agencies, mostly on the JVM platform. He started with Java but more recently has been working with functional programming in Scala and Elixir. He also has exposure to machine learning.


Superphone (via Toptal)
PostgreSQL, Heroku, Eventbrite, Twilio, Shopify, RabbitMQ, Redis, Cassandra...
eBay, Inc.
Docker, Cassandra, spray, Akka, Scala
Support Vector Machines (SVM), Genetic Algorithms, Neural Networks




Preferred Environment

Git, Vim Text Editor, MacOS

The most amazing...

...thing I've coded is my own LSTM (a type of deep neural network), trained with musical notation in order to generate some classical music.

Work Experience

Senior Software Engineer

2016 - 2017
Superphone (via Toptal)
  • Developed SMS marketing solution.
Technologies: PostgreSQL, Heroku, Eventbrite, Twilio, Shopify, RabbitMQ, Redis, Cassandra, Play, Akka, Scala

Senior Software Engineer

2014 - 2015
eBay, Inc.
  • Worked as part of an Agile team to deliver new API services that enable very large merchants to bulk list inventory from popular eCommerce platforms.
Technologies: Docker, Cassandra, spray, Akka, Scala

Machine Learning Consultant

2013 - 2014
  • Helped my clients implement and maintain machine learning models mainly in finance and betting.
  • Developed an algorithmic Forex trading system based on pattern recognition techniques. Created models with neural networks and support vector machines, optimized using evolutionary algorithms. Some libraries used: LibSVM, ENCOG, and MOEA. The system currently runs on Dukascopy Bank JForex platform.
  • Designed and implemented a horse racing betting bot simulation which consumes Betfair API data and takes automatic lay/back decisions using historical data, SVM, and genetic algorithms.
Technologies: Support Vector Machines (SVM), Genetic Algorithms, Neural Networks

Senior Software Engineer

2012 - 2013
  • Developed a new Argos eCommerce website using IBM Websphere commerce platform.
  • Developed faceted search with Adobe Mercado Search Engine.
  • Migrated to SOLR search engine.
Technologies: Apache Solr, Java, IBM WebSphere

Agile Software Developer

2010 - 2012
  • Designed and developed a campaigns and promotions service using REST and DDD principles.
  • Developed and maintained the main customer services (supporting more than a few million customers) using Spring and Hibernate.
  • Built a CRM and call center application using Ruby and RoR.
Technologies: jQuery, Cucumber, RSpec, Ruby on Rails (RoR), Ruby, Hibernate, Liquibase, Concordion, Hamcrest, Mockito, TestNG, JAXB, JDBC, Spring

Software Developer

2008 - 2010
  • Developed the back-end services for a social TV platform.
  • Designed and developed a search and recommendation platform on top of Apache SOLR and Autonomy IDOL.
  • Modularized the platform using OSGi and Apache Felix.
Technologies: Apache Solr, Jersey, Apache Felix (OSGI), Apache Camel, ActiveMQ, JAXB, Hibernate, Spring

Sofware Developer

2005 - 2008
  • Developed Vaio Europe websites using Spring MVC, JSTL, Hibernate, and Lucene.
  • Developed Sony product API and service using Mule, Hibernate, Lucene, Spring, Groovy, and REST Principles (Restlet mainly).
  • Oversaw performance monitoring and tuning of all Sony Europe sites (approx. 2.5 million hits per month) like JVM monitoring, garbage collection tuning, and profiling.
  • Developed and created the technical design for Sony Eurasia’s main unified navigation solution using technologies like Grails, Rome, jQuery, Spring, Quartz, and JMX.
  • Developed and created the technical design of Sony Survey application using Jetty, Spring MVC, Jakarta Tiles, Castor, JAXB, and Spring WS.
Technologies: JVM, Performance Tuning, Restlet, Grails, Apache Lucene, Hibernate, Spring, Java

Large Merchant Integration System

Integration between eBay marketplace platform and the most popular eCommerce systems like IBM commerce using Scala, Akka, Spray, Cassandra, and Docker.
2001 - 2005

Bachelor's Degree in Computer Science

Ege University - Turkey


Apache Cassandra™ 3.x Developer



Deep Learning Specialization



Functional Programming Principles in Scala



JDBC, Apache Lucene, JAXB, Liquibase, jQuery, spray, Eventbrite API, Scikit-learn, Twilio API, TensorFlow


ScalaTest, Vim Text Editor, ActiveMQ, Apache Solr, RSpec, Cucumber, Jenkins, Apache Maven, SBT, Git, RabbitMQ


Akka, Phoenix, Play, Hibernate, Spring, Grails, Restlet, Apache Camel, Apache Felix (OSGI), Jersey, TestNG, Mockito, Concordion, Ruby on Rails (RoR)


Java, Elixir, Scala, Elm, Ruby


Functional Programming, Test-driven Development (TDD), Java Performance Optimization, Design Patterns, REST, Agile Software Development, Functional Reactive Programming, Pair Programming


Cassandra, MySQL, PostgreSQL, Redis


MacOS, JVM, IBM WebSphere, Shopify, Twilio, Amazon Web Services (AWS), Heroku, Docker


Performance Tuning, Hamcrest, Neural Networks, Genetic Algorithms, Support Vector Machines (SVM), Eventbrite, Domain-driven Design (DDD), Machine Learning

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