As a freelance consultant I solve the challenges of my clients in various areas:
Whether challenging "greenfield" projects, refactoring legacy systems or "rescue missions" - I solve problems. Using the right tools, direct communication and agile methods.
- Team Server Migration/Upgrade/Development 2013
SAP Center of Excellence, Walldorf (via Gulp)
Migration of an existing large Redmine instance, upgrading to the latest version, new development of Redmine plugins.Redmine, Ruby, Chef
- Stealth Mode Startup 2013
Rails 4 (beta), RSpec, Turnip/Gherkin, Devise, PostgreSQL, Chef
- Datacenter Management (1&1, Karlsruhe) 2012
Analysis, consulting, maintenance, extension for a datacenter management application of a very large and well known European ISP.Ruby, JRuby, Rails 2, Rails 3, PostgreSQL
- Event Organization Platform (Hotel & eventbs) 2011, 2012
Built an application to allow event planners to navigate through and search for different types of event service providers (e.g. location, restauration, …) based on comprehensive search settings.Ruby, Rails 3, Postgres, Solr
- Video Platform 2011
Prototype development of a vertically scalable video platform. Consulting, training and development.Rails, MongoDB, Redis, Chef, Vagrant
- Mobile Gaming Backend Provider (Scoreloop.com) 2011
Extension and refactoring, in-app purchase, leaderboards, achievements. DevOps consultingRails, RSpec, Chef, Postgres
- Audio/VOIP-Application (Pointoo/gutefrage.net GmbH) 2010
Developed a VOIP application that allows user to submit audio commentary by telephone (PSTN via SIP) for POI / directory site.Ruby, Asterisk, Padrino, Redis
- User Generated Content Site (Pointoo/gutefrage.net GmbH) 2010
Automated server setup with Chef. Ubuntu virtualization with KVM.DevOps, Chef, Cloud-Computing, Virtualization, Routing
- DIY-Community (BurdaStyle) 2009
Internationalization, localization, integration with external systems. Customer from publishing industry.
- BusinessLive 2008
Social network focused of connecting employers and employees using profile matching (Holtzbrinck eLab).
- AllSecur 2006, 2007 (then: "Allianz24")
Extension of the existing direct sales plattform of a leading insurance company.
- FIFAworldcup.com Yahoo!/FIFA 2006
Part of the Yahoo team that built and managed the official FIFA World Cup 2006 websites in various languages.
- Tiscali Games GmbH 2003, 2005
Created a recurring billing system for online games.
- Car Rental 2003—2004
Extension and maintenance of a car rental web application.
- Amazon.de GmbH 2000—2003
Launched Amazon Marketplace in Europe. Localization, customizing for the German version.
A list of the most important technologies I worked with:
MRI: 2.x, 1.9.x
- Perl 5, PHP, Python (In migration projects to Ruby, only)
Agile Methods & Tools
Databases & Search
DevOps & Operations
chef-server, chef-solo, knife-solo, test-kitchen, ChefSpec, Berkshelf, Serverspec
Ubuntu, Debian, CoreOS, RedHat/CentOS
- Virtualization & Containerization
Docker, KVM, lxc, Xen, VirtualBox, Vagrant, VMWare
- Cloud Infrastructure
Amazon AWS, Rackspace Cloud, Digital Ocean
nginx, unicorn, varnish, Apache, Phusion Passenger, munin, nagios, monit, …
CloudOcean Mobile Application, 2013-2014
(CloudOcean.app was discontinued in 2014)
CloudOcean was a native iOS application for iPhone, iPad and iPod touch (3rd generation) to manage virtual servers with the popular cloud hosting provider DigitalOcean.com
Using CloudOcean you can quickly launch a new server instance or scale an existing instance to changing requirements.
Existing SSH applications are integrated when they implement the ssh:// url handler.
Is it Rails? Web Application, 2009-
This application provides a quick and easy way to find out whether a web application is based on Ruby on Rails or not.
It uses a specially developed fingerprinting engine that makes an assessment in terms of specific characteristics of Rails apps.
Started in early 2009 over 7,000 applications have been identified as Rails applications.
- Ruby on Rails
- Twitter Bootstrap
Open Source Projects (excerpt)
digital_ocean RubyGem, 2013
DigitalOcean is an US cloud hosting company with data centers in New York and Amsterdam. My rubygem provides an easy to use interface to their REST-API to manage virtual servers. Uses travis-ci, codeclimate and coveralls to ensure code quality and test coverage.
knife-digital_ocean RubyGem, 2013
To integrate DigitalOcean into the Chef DevOps framework, I've created a plugin to chef's cli knife. This allows bootstrap servers with a single command line command. Supports traditional chef-server environments and chef-solo using knife-solo or custom bootstrapping commands. This is one of the very few open source plugins to knife that has some tests at all.
hetzner-api RubyGem, 2010
I have published and maintained an open source Rubygem to interact with their API. This allowed me to automate some infrastructure tasks using Ruby. With the rise of more scalable cloud providers like AWS, DigitalOcean or Heroku, this is probably only be interesting for legacy projects.
onlinebrief24 RubyGem, 2013
Onlinebrief24.de is a German pdf to snail mail service. My rubygem provides a fast and easy way to deliver those pdfs to their API using SFTP.
This allowed me to automate various invoicing workflows within a SaaS application.
mvg-live Rubygem, 2012
Because there is no official way (no OpenData) to check the live timetable MVG live of the city-owned public transportation of Munich (MVG) on the command line, I've reverse engineered their GWT-based AJAX data feed and build a small ruby application for the console. An extra option to output JSON instead of human readable text is included.
Ruby User Group Munich 2008-2011
Founded the user group, did all the organization work and held some talks.
edX / BerkeleyX
CS169.1x: Software as a Service
CS169.1x teaches the fundamentals for engineering long-lasting software using highly-productive Agile techniques to develop Software as a Service (SaaS) using Ruby on Rails.
CS169.2x: Advanced Software as a Service
CS 169.2x is the second half of University of California, Berkeley's semester long course on Software as a Service.
Terms & Conditions
I am available for projects both directly as a freelancer or as part of Moriz GmbH.
I usually bill by the hour. Due to lack of sustainability for both sides and uncontrollable project risks for me I'll reject fixed-price projects, unless a sufficient specification is provided.
I am happy to create a specification as part of a consultant project with hourly billing.
My fees vary according to the task, location and challenges to be solved.
What I prefer:
- Agile environment with good test coverage
- Direct collaboration with decision makers and product owners
- Project duration longer than 6 months
- Remote work or
- On-site project in Berlin, Munich or Vienna.
Things that I surcharge for:
- Legacy projects (depending on the technology, code quality and scope)
- No agile project management
- "Red Tape"
- Short-term "emergency" mission
If you need a third-party recruiter to hire me, this will cost you additional money (~15-30% depending on the recruiter). I can't control this commission.