Hi, thanks for stopping by!

My name is Sven Tantau and I am German by birth, Norwegian by my mom and part-time African by choice.
I started playing with technology at an early age, and gladly my parents always supported this hobby of mine. I really appreciate how many doors it opened for me since then.
If I am not busy on my keyboard, I like to hang out with my friends, travel and spend quality time with my girlfriend wife.

I am very proud and happy to be a co-founder of nebenan.de, where I had 5 years the privilege to work with an awesome team to bring neighbors a bit closer together.
Currently I am working as co-founder of the gut.org invest GmbH with an equally awesome team to make impact investing easier. bcause.com
Below is more information on the services I offer (currently not available!) and the projects I have been doing.
If you have any questions or just want to talk about tech-stuff, please do not hesitate to contact me.

Cheers!

Software Development

I had my first job as a programmer in 1998 building perl based websites. Since then I have worked on many applications, ranging from simple content management systems over community software to ERP systems and business process automation. I also enjoy to work on mobile phones or writing software for your startup.

Systems Integration and Telecommunications

Working for and with multiple internet service providers I had the opportunity to build and migrate WiMAX networks, write and deploy various services and play with expensive hardware. With a preference for open source software I help companies to customize available solutions to their needs and make existing components work together.

Security Consulting

I also offer security consulting with focus on web applications and general information security. I have discovered security problems in web applications, kernel modules, as well as in consumer software like ebook readers or video players. I also reverse engineered firmware to break authentication methods and hunted for backdoors.
On the defending side I've build and integrated firewalls, IDS or NACs like packetfence.

Programming Languages:

At the moment I get most work done with ruby, perl, javascript or c.
But I've also worked with java, objective c, x86 asm or scripting languages like php, python, basic dialects or query languages.
Yes, I do automated testing; I use version control and I love CI.

Operating systems:

Linux preferred. Accidental knowledge about Windows, BSD and Mac. I also picked up some cisco skills along the way.

Software I've setup, used and maintained:

Postgresql, MySQL/MariaDB, IBM-DB2
Apache, Lighttpd, nginx, HaProxy
Postfix, Exim, Courier
Freeradius, Radiator, Samba, Squid, cvs, svn, git, dhcpd, nfs, pppoe, asterisk, openfire, rrdtool, zabbix, snort, packetfence...
Many proprietary NMS systems like snmpc, other monitoring solutions, firewalls, more or less everything you would find inside an ancient or modern ISP.

Hardware:

Experience with smart card programming.
Radio systems from multiple vendors like Alvarion/Telrad, Airspan, Ceragon. WiMAX, Microwave, VSAT installations. And some mobile devices.