Profit from sustainable IT

"Sustainable Software": high security & data sovereignty by decentralized Open Source architectures

Open source software makes it possible to build long-term reliable and secure systems that exactly meet your requirements. Open Source software is free of charge and transparent, providing you independence of software companies that are very interested in your data. Take advantage of these benefits and become the master of your data and IT again! Among other things, I will show you simple possibilities that Edward Snowden considers good.

"Sustainable Hardware": durable and energy-saving hardware with simple maintenance

High-quality devices are reliable from 5-8 years, cheap to maintain and purchase as second-hand products. Minimize your technological, environmental, and financial footprints by using IT equipment with low investment, maintenance and energy costs. An increasing number of manufacturers are focused on fair and resource-conserving production processes.

The result: reduced costs, improved reliability, increased security and eco-friendly IT.

With sustainable software and hardware, you can simultaneously save money and reduce your ecological footprint. In addition, you benefit from reliable and secure systems with full control over your data. Get involved with this sustainable digital-electronic movement and you'll experience benefits exceeding your new investment.

Hi! My name is Mathias Renner.

For 8 years I’ve advised clients on various aspects of IT.

After 5 years of experience with traditional IT practices, my interests lead my focus to sustainable IT solutions. IT is the backbone of the digital age we live in, and only “sustainable” IT solutions offer potential for a free and fair future for all citizens.

I hold a M.Sc. in Information Systems with a specialization in energy efficiency and data analytics.

Your Benefits



I can provide advise in almost any IT topic: websites, smartphones, secure communication, networks, Docker... Just ask me!

Professional Network

Professional Network

I built a network of like-minded professionals, who will help you in case I should not be available myself.



8 years of experience, a master's degree in IT and many satisfied customers speak for themselves. Be my next satisfied customer!

Remote maintenance

Remote maintenance

Small issues can be solved remotely and on short notice. That way you save expenses for my journey.

Satisfaction guarantee

Satisfaction guarantee

My customers only receive a bill, when they are 100% satisfied with my performance. Without exception.

A matter of heart

A matter of heart

Acting sustainably is a matter of heart to me. You will feel it!


Docker, Inc.
Software company, USA

Udo’s Fahrschule
Driving school

Donum Vitae in Bayern e.V.
Counseling Center Bamberg

Doctor’s office Dr. Hohmuth
General practitioner

SBBZ Bamberg
Clinical practice for logopedics

Dance School

Fire Fighters Bamberg, City Association BA
Music lessons

Doctor’s office Kerstin John
in Baby- & Elternzentrum BA

You only receive a bill when you are 100% satisfied.

Without small print.

Per Hour


  • incl. 100%
    satisfaction guarantee.

Journey (if necessary)


  • In Berlin.
    0,40 €/km elsewhere.
    If applicable I use a bike.

Recent English articles in my blog


Why everyone has something to hide

Many people are convinced that they have nothing to hide. On closer inspection, this unfortunately turns out to be a premature conclusion. I will try to explain this complex problem in an understandable way.

I look forward to getting in touch with you!

+49 151 599 29 599

In case I cannot pick up the phone, please leave a message to my mailbox. I'll report back to you in a timely manner.

Berlin (Schöneberg district)

Send me a message

 Hinweise zum Datenschutz habe ich gelesen.