Fullstack
Management
- concepts
- mockups
- estimates and offers
- community management
Consulting
Mobile
Web Frontend
- HTML
- CSS
- LESS
- Accessibility
- JavaScript
- vanilla
- jQuery
- prototype
- React
- Angular
- gulp
Authentication
- oAuth
- SSO Kerberos NTLM
Desktop Frontend
- C#
- Delphi
- Java
API Integration
- Paypal
- Google
- Mailchimp
Backend Programming
- PHP
- Perl
- Python
- nodejs
Database
- MySQL
- SQlite
- Oracle
- Postgres
- DB2
System Administration
- Apache
- FPM
- Monitoring
- Postfix, QMail, Exim
- Dovecot
- Firewall
- VPN
System Programming
- PAM
- Krone C
Network Protocols
- lots of knowledge on HTTP and related RFCs. wrote my own HTTP 1.1 compatible client library for DokuWiki. able to manually speak simple HTTP via telnet.
- lots of knowledge about SMTP and related RFCs. contributed to the txthinking/Mailer library. can speak simple SMTP via telnet
- lots of knowledge on mail encoding. wrote my own classes to construct multipart mime mails and correctly encode UTF-8 mails
- basic knowledge on POP3 and IMAP. used to be able to speak POP3 via telnet when it was still popular
- SNMP
- LDAP ActiveDirectory
- wrote my diploma thesis on ad-hoc routing protocols
Operating Systems
- use and can manage Windows but it's not my favorite system
- started learning about and administrating Linux systems during civil service in 1999
- worked as system administrator for CosmoCode for several years
- fluent with Debian and Arch Linux, but worked on Redhat, SuSe, HP-UX and other unix-like systems
- able to indentify and debug common problems on Linux including init and systemd, udev, xorg and other core systems
Hardware
- build my own PCs since after I got my first own computer (a 386 somewhen in the early 90ies)
- can set up general network equipment and make network cables (started with 10baseT but know how to crimp modern CAT cables and fit patchpanels)
- built a 3D printer from a kit
- there's a yet unfinished Raspberry Pi project where I use GPIO to talk to sensors
- can solder but have not much knowledge in electronics eg. I can built circuits others designed but can design my own.