Karel Zak
Principal Software Engineer at Linux & Open Source
Budweis, South Bohemia, Czechia
Summary
🤩
Rockstar🎓
Top SchoolKarel Zak is a Principal Software Engineer with 26 years of experience specializing in low-level Linux system programming, shared libraries, and critical utilities maintenance for Red Hat Enterprise Linux and Fedora. A long-time util-linux maintainer and back-end contributor to flagship projects like e2fsprogs, he has deep expertise in libblkid, device-mapper integration, and kernel-facing tools such as dmesg and zramctl. He blends hands-on C, POSIX, and shell development with build-system craftsmanship (autotools, RPM) and a history of database and PostgreSQL contributions. Known for leading community-driven projects, he routinely navigates upstream collaboration, complex bug fixes, and API stability across production distributions. Based in Budweis, Czechia, he pairs pragmatic engineering with a knack for uncovering subtle kernel–userspace interactions that improve reliability at scale.
26 years of coding experience
6 years of employment as a software developer
Ing., Ing. at University of South Bohemia České Budějovice
English
Stackoverflow
1reputation
0reached
1answer
0questions
Github Skills (30)
filesystem10
system-programming10
low-level10
c-programming10
c1110
file-operations10
c1710
device-mapper10
low-level-programming10
fileio10
scripting9
debug9
debugging9
linux-kernel9
bash9
Programming languages (9)
Github contributions (5)
util-linux/util-linux
Dec 2006 - Jan 2023
Role in this project:
Back-end Developer
Back-end DeveloperContributions:431 reviews, 11339 commits, 1805 PRs in 16 years 4 months
Contributions summary:Karel's contributions primarily involved modifications and additions to the util-linux utilities, including the `dmesg`, `lslogins`, and `zramctl` tools. They focused on code cleanup, bug fixes, improvements to the user interface with JSON and hyperlink output, and implementing new features such as a compression ratio for zram devices. The user demonstrated an understanding of core system utilities and Linux kernel interactions through the integration of new functionalities and bug fixes.
tytso/e2fsprogs
Sep 2005 - Oct 2009
Ext2/3/4 file system utilities
Role in this project:Back-end Developer
Back-end DeveloperContributions:10 commits in 4 years 1 month
Contributions summary:Karel contributed significantly to the `e2fsprogs` repository, a collection of file system utilities, primarily focusing on the `blkid` library. Their work involved fixing bugs in the cache validation process, adding support for detecting software suspend partitions, improving VFAT detection, and adding GFS/GFS2 support to `blkid`. Furthermore, they enhanced the library by implementing device-mapper support, including the use of /sys/block/dm-<N>/dm/name to get device names, and added support for parsing compressed modules.
vfstarballfinderadministratorfilesystem
Find and Hire Top DevelopersWe’ve analyzed the programming source code of over 60 million software developers on GitHub and scored them by 50,000 skills. Sign-up on Prog,AI to search for software developers.