Name Jan Kratochvil
English technical: fluent, general: communicable
Born 1979
Sex male
[ PDF | text ]
OpenPGP 1E3AD15E



Fulltime Jobs
DateCompany Description
2006/07-...Red Hat LLDB development, ELF, DWARF, ptrace, unwinding, ABI, formerly GDB development
2005/04-11VA Linux Systems Japan Linux kernel based software development
2004/01-11Sun Microsystems Java Enterprise System Quality Assurance (JES QA), technical lead
JES components compatibility analysis, automation of QA tasks, JES testing, QA frameworks pilot deployments, architecture and lead of the team projects, team programming guidelines


Freelance Commercial Projects
Date Description
2005-2006 MMS2: Alternative center for cheaper mobile phones multimedia messages (MMS) (service web)
Web interface was outsourced. Commercial service management held together with company JK-Invent.
  • Designed to coexist with existing GSM networks service servers
  • MMSE/WAP-Push/web/mail convergency featuring smart transformations
  • Credits charging by ISDN IVR + automatic bank transaction acceptance interface
  • Completed alpha and beta product cycle for mobile phones firmware bugs workarounds
  • Free gatewaying program for customers to avoid targetted GSM operators firewalling
2004 HotelGate: Internet Public Access Gateway
Plug&Play TCP/IP for clients, selectively ticketed and/or free access, simplified interface for reception desks, easy and unified management.
European facility installations provided by JK Labs.
2002-2003 Captive: The first free NTFS read/write filesystem for GNU/Linux
Featured on slashdot.
Analysis of portions of 80MB+ i386 disassembly dumps of MS-Windows XP kernel and ntfs.sys for the first binary compatible reimplementation of the undocumented XP kernel subsystems.
Written TraceFS: Microsoft Windows Kernel API Tracer: MS-Windows Kernel API Tracer as native W32 kernel hooking driver for run-time analysis of the NT Cache Manager XP kernel subsystem.
UNIX userland of Captive provides GnomeVFS interface to the MS-Windows kernel based MS-Windows filesystem isolated by the CORBA/ORBit interface.


Contractor Jobs
DateClient Description
2001-2002Advanced Telecom Services Mobile technologies
  • MMS framework client via EuroTel GSM operator by technologies GSM MMS, Perl, XML, SOAP
    Project included pilot MMS Center debugging with Ethereal (external link), fixes of Ethereal (1, 2).
  • Multimedia EMS support implemented by GSM::SMS patch
  • Implementation of protocol BIP (based on Nokia CIMD2 protocol) for GSM SMS Center direct communication by extending gnokii (external link) for EuroTel GSM operator
1999-2000SuSE Partition Surprise: GPLed Partition Magic clone
Project was completed as a team work. The code is based on Gnome technologies. As one of the subtasks to keep system bootability I implemented Int13Sniff to ease Microsoft boot loaders disassembly across partition modifications.
2001-2002ReadyNote Mobile technologies for embedded devices
  • Completed debugging of gnokii (external link) GSM software modem for Nokia 5190
  • Port of gnokii and my mdsms (Mobile Device SMS Tool) to embedded uClinux (external link)
1999-2003JKLabs System administration of GNU/Linux and FreeBSD, techsupport: GuestNET, Eclipse, GlobaLoop, Fresco
Ad hoc technical support challenges such as i386 IRQ redirector, Middleman port (HTTP proxy ported to FreeBSD) or ssht (Unattended intranet host accessibility by SSH tunnel).
2001 GTS tac_plus auth: Cisco TACACS+ NAS host based authorization
1999 Unicom Technical translations from English
1998-1999Geoinvest Mobile technologies, embedded devices
  • 332: AmigaOS kernel port to embedded Motorola 68332
  • Siemens M1 GSM modem daemon for GPS, client/server setup, remote GSM terminals
1999 TENcom Trade Mobile technologies
1998 European Law Students' Association STEP: Custom web database application incl. fixes of PHP and PostgreSQL
1993-1996Profes J&K PC assembly and customer service
1993 Japhila StampMan: Database application (MS-DOS: Pascal, plainTeX)


1997Bronze medal in the International Olympiad in Informatics, South Africa - Cape Town
19972nd in an MO-P national contest - mathematics Olympiad, the programming category
19971st in the International Competition in Programming
19964th in the International Competition in Programming
19957th in the Central European Olympiad in Informatics


Experience Summary
Major Areas mobile technologies, filesystems, embedded devices
Platforms GNU/Linux/i386/UNIX/FreeBSD, W32 kernel, Amiga/680x0, MS-DOS, ZX Spectrum, handheld PC-E500S
Languages C (Gnome/GCC), Perl, bash/awk/sed..., Java, C++, Pascal, Basic, REXX, S-Lang, Foxplus, Prolog
Tools/Metalanguages autoconf, automake, libtool, m4, CVS, gettext, bison, flex, ld script, gdb script, Maple V
Assemblers i386/x86_64, Motorola 680x0, Zilog Z80, Intel 8051, MIPS R2/3000, (Hitachi SH-8)
WWW-Related HTML/XHTML, CSS, PHP, SQL (PostgreSQL, MySQL), JavaScript, CGI
DocumentationplainTeX, LaTeX, DocBook, DocBook Lite, XML/NS/Schema, gtk-doc, nroff, pod
Libraries Gnome/GTK+/GLib, POSIX/BSD/SysV/threads/sockets, X11, OpenGL, NCurses, S-Lang, GnomeVFS, libxml, libneon, SVGALib, NIS, Qt,...
Filesystems ext2, FAT, AmigaFFS, ISO-9660
Certificates RHCE 110-518-099


My Own Free Projects
Detailed listing available at:
PlatformAvailable Free Projects
UNIXCaptive, Partition Surprise, PerlMail, mdsms, badblock-guess, xbelnormalize, IRCon, Gnome xBill, tcpoverudp, udpgate, harpy, netdnsspoof, pipebuf, inetdmx, line9k, ppp9k, redirector-ad, tac_plus auth, SSH-1 patch, KIX, ssht, Middleman port
UNIX-devel332, AutoGen, checkstatic, cvsutil, staticbuild, cvsbranchdiff, Int13Sniff, KernelWare, mot2as, wllib, vblib
WebRotation, My::Web, PHP Web, FordFulk, Heat, Islet, STEP, kewensis
AmigaLaserGame, ResRAM, PortDiag, Casio-A, ShortRel, QueryDev, SClock
MS-WindowsTraceFS, WinVNC hide
MS-DOSDOSWatcher, Descent 2 no-CD
PatchesGNU Libtool fix, GSM::SMS patch, Linux NTFS GnomeVFS, Mutt speedup, netstat -p, libxml2 fix, Ethereal MMSE fix, Ethereal WSP patch, Glade -w, PHP-3.0b6 fix, PostgreSQL-6.3 fix, mod_auth_tacacs client, D1X TCP/IP