Oliver Kriz, Developer in Berlin, Germany
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Oliver Kriz

Verified Expert  in Engineering

Back-end Developer

Berlin, Germany
Toptal Member Since
July 7, 2020

Oliver is a passionate back-end engineer with a data-driven mindset of a hacker—thinking out of the box—and 15+ years of professional software development experience in over seven different industries. Oliver has an affinity for analyzing, digitalizing, and optimizing business processes and workflows. His main tech stack is PHP with MySQL or PostgreSQL—either plain or with Symfony. He's interested in smaller hourly projects in high-tech industries to expand his network and broaden his horizons.


Foo.ag | Financial Engineering
Bash, Unix, MacOS, Jenkins, Groovy, Python, JavaScript, PostgreSQL, PHP
Symfony, PhalconPHP, Bash, Unix, MacOS, Jenkins, PostgreSQL, MySQL, JavaScript...
Carspring Services GmbH
Symfony, PhalconPHP, Bash, Unix, MacOS, Jenkins, PostgreSQL, MySQL, JavaScript...




Preferred Environment

Unix, Jenkins, Atlassian, JetBrains, PhpStorm, MacOS

The most amazing...

...thing I've developed is probably a customized A/B testing solution (and bots to help me with tedious everyday tasks like online dating).

Work Experience

Senior Software Engineer | Technical Team Lead

2017 - 2020
Foo.ag | Financial Engineering
  • Created and fully integrated a continuous integration system containing unit, database, user acceptance tests, deployment tools for the quality assurance team, and automated code style reviews on each pull request.
  • Designed and developed critical business units like pre-investment cost prognosis calculation and annual account statements.
  • Directed and led the software development for a team of six developers, which included coordination with other teams to optimize the overall companies software quality and processes.
Technologies: Bash, Unix, MacOS, Jenkins, Groovy, Python, JavaScript, PostgreSQL, PHP

Lead Developer

2017 - 2017
  • Led a cross-functional IT development team including QA, frontend, backend, BI, and database engineers.
  • Analyzed and optimized all business processes, automized repetitive and ongoing tasks.
  • Planned and coordinated the new architecture of IT stack in PHP 7.1, PostgreSQL, and Phalcon Framework.
  • Maintained the old legacy stack in PHP 5.6, MySQL, and Symfony2 as well as started the migration to the new architecture.
Technologies: Symfony, PhalconPHP, Bash, Unix, MacOS, Jenkins, PostgreSQL, MySQL, JavaScript, Python, PHP

Lead Developer

2015 - 2017
Carspring Services GmbH
  • Jumped into the project as the interim CTO and took over a team of six engineers.
  • Introduced BI into the tech stack along with designing dashboards and defining their business requirements.
  • Designed and implemented a fully autonomous marketing automation XML feed based on Facebook and Google marketing.
  • Integrated with more than 25 third-party REST/JSON and Soap/XML APIs for data flows (import and exports).
Technologies: Symfony, PhalconPHP, Bash, Unix, MacOS, Jenkins, PostgreSQL, MySQL, JavaScript, Python, PHP

Technology and Development Transfer from Germany to South East Asia

I handled the project and software development migration from Berlin to Singapore, which included building up and training the IT department and working as a consultant to ensure common best practices were applied. We brought the code and knowledge to Singapore and the technology culture as well.

Bootstrapping Lendico Germany

I handled this project from scratch to delivery in three months. This included planning, developing, and launching the peer-to-peer credit platform Lendico Germany. Lendico was an enormously successful venture under the accelerator Rocket Internet and was later sold to ING bank.


PHP, HTML, JavaScript, SQL, PHP 7, XML, Python, Java, C, C++, C#, UML, CSS, Groovy, Bash


PhpStorm, Git, Subversion (SVN), Jira, Jenkins, GitHub, Bitbucket, Slack, Optimizely, Visual Website Optimizer, Adobe Target, JetBrains, Atlassian, Google Analytics


OOP Designs, Back-end Development, Domains & Hosting, eCommerce, SOAP, People Management, Bots, Scraping, Web Crawlers, A/B Testing, Multivariate Testing, APIs, IT Security, Server Administration, Coaching, Business Coaching


Symfony, PHPUnit, Codeception, Selenium, Symfony 2, PhalconPHP, Yii, Zend Framework


jQuery, FPDF


Agile Software Development, Agile, REST, Management


MacOS, Amazon Web Services (AWS), Docker, Unix


MySQL, PostgreSQL, Memcached, Redis, Elasticsearch, JSON, JSON/XML Schemas, Databases

2010 - 2012

Master's Degree in Computer Science and Media

Beuth University of Applied Science (TFH) - Berlin, Germany

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