Our OpenSource Work

As part of our work, and for fun, we naturally spend a lot of time looking at code of OpenSource projects. As part of this time spent on the code we try to contribute back to the community as much as we can if we spot something missing, wrong or misleading. These contributions are not usually cool new features, but quite often simple things like:

  • documentation fixes
  • missing documentation
  • typos
  • minor style fixes

But of course every now and then it will also be something that one might actually notice when working with the product.


While we always encourage everybody to also participate in the OpenSource community we do recognize that this is not always possible due to workload, expertise or maybe even corporate policies. At any given time we will usually have a significant backlog of issues or improvements that we are working on - but somehow there are never enough hours in the day to get caught up. For this reason we have created our patronage program for companies or individuals that still want to give something back but can't do so themselves.

We will keep this page updated with things that we currently lack the time to properly focus on and over everybody the opportunity of becoming a patron for / adopting these items. There is no fixed process for adopting an issue, so please feel free to contact us if you wish to give something back. We will of course provide you with a proper invoice for anything you contribute.

What our patrons get in return:

  • eternal gratitude not so much from us but from the rest of the community
  • PR on Twitter, mailing lists, Jira
  • their logo on this page

Previous sponsors



We’re an advanced tech and data start-up backed by Allianz based in Hannover and Munich. We enable our clients to utilize their various online and offline data for a best possible customer engagement and a highly personalized user experience.

We’re on a quest for customer insights which started for us, the team of founders, over a decade ago: Since then we designed, developed and operated advanced online research tools and solutions for well-known global brands. We years of hands-on experience under our belt applying the latest big data technologies, the newest analysis tools and advanced statistical methods on real-world problems. Now we are using that knowledge to build the future of Open Source Customer Data Platforms – jointly with our co-development partners. – Think of us as technology geeks with a knack for solving business problems with data.

Sponsored Projects

  • Transparent Data Encryption functionality for Apache Kafka

Current Projects

Transparent Data Encryption functionality for Apache Kafka

Our previous contributions

The following is a curated list of some of our contributions to the various open source projects that we are working on and have worked on. We have consciously omitted more mundane documentation and style fixes from this list.

Apache HBase

Lars Francke

Remove onelab and include generated thrift classes in javadoc

Apache Hive

Lars Francke

Improve documentation of OVER clause

Lars Francke

UDF degrees() doesn't take decimal as input

Apache Kafka

Sönke Liebau

Connect Producer and Consumer ignore ssl parameters configured for worker

Sönke Liebau

Connect Rest API allows creating connectors with an empty name

Sönke Liebau

Clarify handling of connector name in config

Sönke Liebau

Console Consumer overrides auto.offset.reset property when provided on the command line without warning about it

Sönke Liebau

Move check for super user in SimpleAclProvider before ACL evaluation

Apache Knox

Lars Francke

Document the --master and --generate parameter for the create-master command

Apache NiFi

Lars Francke

State Manager documentation link wrong

Sönke Liebau

Add correct parsing of content type in accordance with RFC 2045

Apache YARN

Lars Francke

WintuilsProcessStubExecutor.startStreamReader leaks streams