Dirk Jagdmann

Coder

I'm a software developer currently working in Silicon Valley on network optimization software. I have a strong background on Unix/Linux/BSD programming which I'm doing since 1995. But apart from 32/64bit C++ code I have also done lots of 8bit assembly coding on microcontrollers and the Commodore 64 (that was in the late 1980's). And since 1997 I maintain various Internet servers/websites and have built and maintained a lot of typical web applications, mostly done with PostgreSQL and Embperl.

I live in Santa Clara, California and can be contacted by email to dirk@jagdmann.de or by phone 415-830-6442. Most of my (free) Unix software is available on my website llg.cubic.org, while my private website http://cubic.org/~doj contains lots of (unsorted) stuff.

My Resume

A shorter printable version of my resume is found in the English PDF.

May 2017 -- present

Principal Lead Linux Developer at Akamai Technologies, Santa Clara, CA

Implement security features for Bot Manager: encryption of customer data for safe transport, HTTP body manipulation, HTTP request routing
Design/implement a SaaS system for HTTP request processing: distributed key/value store per datacenter, Lua engine for HTTP request manipulation, self monitoring for rapid exception handling, crash resiliency from HTTP proxy server

Feb 2010 -- Apr 2017

Linux Developer at Riverbed, Sunnyvale, CA

Worked on network protocols (iSCSI, NFS) for the SteelFusion product.
Worked on Microsoft Exchange optimization of the SteelHead appliance (MAPI protocol). Implemented support for Outlook Anywhere (RPC over HTTP). Developing a heavily multi-threaded Linux C++ application to handle thousands of MAPI TCP connections and apply optimization techniques to them.
Maintained the Riverbed internal version of Wireshark (implemented in C). Developing new features/protocols for Linux and Windows.

Oct 2007 -- Jan 2010

Lead Linux developer at NeoCatena Networks Inc, Sunnyvale, CA

Architected and implemented the RF-Wall product, a RFID security appliance. The RF-Wall system is a collection of server processes interfacing RFID readers, evaluating and possibly manipulating RFID tags as they are handled by the readers. Written in C++ and using PostgreSQL as data storage. The appliance uses several TCP and UDP network protocols to interface readers and backend systems.

Sep 2005 -- Jul 2007

Lead FreeBSD developer at Secion GmbH working on software for Arcor/Vodafone, Hamburg, Germany

Development of a DynDNS System in a high-availability setup: mod\_perl front end, PostgreSQL data storage, dynamically configured bind nameservers.
Architected a high-volume download platform for voice mail. This is a high-availability system of 15+ nodes in multiple locations, communicating with XML over HTTP requests, converting A-law PCM to MP3, utilizing large NFS storage. Implemented as perl and C++ server programs.
Installation and maintenance of web, FTP and mail servers with FreeBSD.

Jul 2003 -- Aug 2005

Linux software developer at DN-Systems GmbH, Hildesheim, Germany

Implementation of a web-application for medical services accounting with perl, PostgreSQL running under Linux and mobile data entry with iPAQ PDAs and pc-card smartcard reader.
Maintained and improved the RFDump tool, a RFID security program for Linux written in GTK and C.
Programmed the GTK-Installer of the Linux Security Local Auditing Daemon V2.
Designed a test-suite for email server load tests as Linux perl scripts.
Development of an OVAL to NASL proof-of-concept compiler using a XLST processor as the XML compiler.

Jul 1998 -- Jul 2001

Linux administrator and software developer at Reese-Data-Exchange, Hamburg, Germany

Installation and maintenance of web, FTP and mail-servers.
Development of web-applications with perl and PostgreSQL: real estate sales portal for a local bank, online-shopping sites.

Skills

From my current and past projects I have gathered expertise in the following areas:

C/C++ development
perl development
PostgreSQL and PL/pgSQL, SQLite
network (protocol) Development: TCP/IP, HTTP, UDP (broad-/multicast)
OpenGL and general Audio/Graphics development
Linux/FreeBSD software development, administration and operating system customization
Website/Webservice development
Microcontroller development: MSP430, Atmel AVR, 6502
Hardware drivers, Linux kernel and similar tasks

One more comment on programming languages: All imperative and object oriented programming languages are more or less the same. If you know how to use one, you can easily adapt to others of the same kind. So although I have listed C/C++ and perl in the above list, I can do development in similar languages as well which would include: Java, Python, Ruby, PHP, sh, pascal and whatever will come in the future. Due to my background in hardware and microcontroller development (and my history on the C64) I know assembler for a number of processors as well.

Contributions to Free Software Projects

Wireshark
Network protocol analyzer, changes mainly to HTTP, SSL and DCE/RPC dissectors.
srm
Secure file deletion for POSIX systems.
dmx4linux
A driver suite for the Linux kernel to interface DMX hardware using for lighting.
Catweasel linux driver
A linux driver for the Catweasel MK3/4 Floppy Controller.
Cisco CMXML Services
A collection of cmxml services for Cisco's 79xx phones.
pg_trompe
Multi-Master replication for PostgreSQL.
multimidicast
Transmits and receives MIDI data via UDP multicasted on the LAN.