Zygo Blaxell

A current version of this resume is available on the Internet at http://www.hungrycats.org/~zblaxell/resume.html.

Contact Information

Phone: (613) 220-2927
E-mail: zblaxell@hungrycats.org

Profile

An accomplished problem solver with over 14 years' experience in systems-level software development and information technology operations, building mission-critical systems from open-source tools. Key strengths include a demonstrated eagerness to learn, an impatient desire to get things done, and fanatical attention to detail. Equally comfortable with highly structured, peer-reviewed product change management processes and MacGyverish mash-ups of software and hardware.

Skills and Experience Summary Table

Years	Area	Specifics
14	Linux	Application development, system administration, network administration, kernel and device driver development, security analysis, software porting. i386 and Sparc platforms. Experienced with Debian and Red Hat distributions, maintained own distribution for a year or two.
14	GNU tools	Fax software, C/C++ development tools (gcc/g++, gdb, make, cross-compilation), Subversion and CVS administration.
14	Shell scripting	Bourne shell, sed, Awk, regular expressions, etc.
13	Perl	Database administration, CGI/WWW development, application proxies, log analysis and reporting tools, cross-platform testing.
12	Information Security	Internet firewall design and implementation, security policy, code audit and verification, intrusion analysis and recovery, Unix host security, some cryptography.
12	Internet Server Administration	Apache, Perl, CGI, INN, Bugzilla, MediaWiki, sendmail, bind on Linux. Entire process from LAN wiring and DNS setup to end-user custom CGI script development and security auditing. Customized implementations of SMTP, NNTP, POP3, HTTP protocol servers and proxies.
11	System Administration and Support	Mixed Windows, Unix, Linux, Mac environments. Supported computer science undergraduates, small software development companies, large CAD environments.
9	C++	Developing and porting applications (IBM Visual Age, Microsoft Visual C++, GNU g++ on Unix and Win32). Custom EDA tools and very large image processing.
7	C	Most experience in Linux environment, with intermediate experience in other Unix environments and Windows 95/NT. Strong knowledge of ANSI standards and portable software development techniques. Much experience debugging 3rd-party programs and libraries, with or without complete source code.
7	Tcl/Tk	Emphasis on portability tools within Tcl, embedded applications, GUI development, distributed processing using agents.
6	Solaris/SunOS	System administration, software porting, cross-platform testing, SunOS -> Solaris migration support. i386 and Sparc platforms.
4	PostScript/PDF	text-to-PostScript translators, automated document layout and formatting, custom report generators from schematic (EDA) data.
3	Assembly Language	Motorola 6809, Intel 8051, 8086. OS-9 real-time operating system and embedded systems. 7 years including hobbyist experience.
3	Microsoft Windows, DOS	Software development in Visual Basic/C++, Borland C/C++, IBM Visual Age C++, network administration. Contributions to the Wine project, a Win32 API replacement for Linux.
1	Miscellaneous Unix-Like OS	FreeBSD, AIX, HP-UX, Ultrix, EP/IX administration and/or software development.
3	Electronic interfacing, digital hardware design	Designed and built controller and data acquisition cards, serial port interfaces, a hardware memory copy accelerator, remote sensors for 6809-based and 80386 ISA-bus systems. Wrote device drivers for thermal sensors, CCD microscope cameras.
2	Qt	Developed software to support readback of circuitry from images of integrated circuits. Tuned performance of drawing operations. Implemented database interface layer.

Software Development Work Experience

Xandros	2008-present

Mandate: Integrate the Linux Bluetooth stack with Xandros's Linux OS products.

(Details embargoed)

Roaring Penguin Software	2008

Mandate: Develop web-based application software for an ad-driven collaborative web site using Linux, Apache, Perl, and PostgreSQL.

Designed and implemented business objects with Rose::DB::Object, Template::Toolkit, and Catalyst.
Contributed to product design and system architecture.
Participated in PgCon 2008 PostgreSQL conference.

Chipworks	2000-2007

Mandate: Design, develop, support, and maintain critical in-house applications for automated image acquisition of integrated circuits and subsequent electrical analysis of the image data.

Linux Application Software Development

Designed architecture of image capture software for SEM (scanning electron microscope) imaging.
Provided documentation during negotiations with suppliers to ensure that the image acquisition system would satisfy technical requirements.
Resolved severe performance problems in image retrieval and display functions of Chipworks proprietary Qt applications.
Integrated support for new camera and stage devices into Chipworks proprietary image capture applications.
Designed and implemented software and operational procedures for correcting registration and calibration problems in image data, reducing or eliminating the need to re-shoot images in most cases.
Designed and implemented a number of distributed image processing systems as required to match changing computational capabilities with changing operational requirements.
Implemented PDF report generator used by the Report Production department to generate reports on paper or PDF for delivery to customers.
Reviewed code written by other developers at Chipworks.

Linux Device Driver Development

Developed complete Linux device drivers for:
- microscope cameras (Polaroid DMC1E, DMC2P; Hamamatsu C4880)
- temperature sensors (HotLittleTherm, Dallas Semiconductor)
- robotic stages (Newport, Precision Instrument)
- frame grabbers (Imaging Technologies Inc.)
Resolved interoperation issues between some SCSI host adapters and some SCSI camera devices. Instrumented a Linux kernel to capture data passing through the SCSI bus for analysis.
Extended the Linux device driver for Promise IDE cards to support some versions of the FastTrak 66, 100 and 133 controllers.
Reverse engineered Windows device drivers to develop Linux drivers as required.

IT Support

Provided detailed analysis of Chipworks requirements for image data storage which resulted in changes to operational procedures and IT purchasing decisions that reduced capital costs by up to 95% and eliminated significant IT administrative overheads.
Researched the causes of disk storage problems which were causing major system outages at least once per year. Requirements for redundant storage and hardware monitoring were established, enabling IT to avoid common failure modes that interrupt service or jeopardize data integrity.
Answered technical questions and resolved problems with Linux, Debian, PostgreSQL, Qt, Tcl/Tk, video drivers, and GNU C++ toolchain as required by members of the IT and R&D departments.
Provided technical details, patches, and analysis as required to fix bugs in open-source software used at Chipworks (especially Debian, PostgreSQL, and ReiserFS).
Operated groupware services such as Bugzilla, Subversion, and MediaWiki within Chipworks.
Responsible for resolving operational issues with all Linux systems at Chipworks that were not resolved by the IT department.
Contributed expertise with tools such as gprof, gdb, gcov, strace, ltrace, valgrind to resolve performance problems and fix obscure bugs.
Built and maintained automated Linux desktop installation CD images for the IT department.
Applied security patches and device driver upgrades to Linux systems as required.
Created Linux-based server infrastructure (file and email servers, firewalls, VPN) for Chipworks Warsaw and Phoenix offices, with automated installer CDs and remote administration capability.
Optimized transport of multi-gigabyte image data sets across the Internet between the Warsaw and Ottawa sites using rsync. Efficiency of a minimum of 60% was achieved despite packet loss rates as high as 75%.
Designed and implemented automated failover for Ottawa site Internet connection using two Internet service providers connected to a Linux-based firewall.
Supported non-x86 and Unix systems at Chipworks (MIPS-SGI, Sparc-Solaris, and Alpha-Linux).

Operations Support

Provided day-to-day end-user support for Chipworks proprietary integrated circuit reverse engineering software.
Developed custom scripts using the Tcl API embedded in the Chipworks software to resolve special-case problems for engineers.
Provided end-to-end support for PostgreSQL databases, including administration, performance tuning, and software development (on client and server).
Implemented a monitoring and reporting system for temperature sensors in Chipworks image capture labs. Quantified the relationship between temperature stability and operational efficiency of the image capture systems.
Analyzed log data generated by automated image capture systems when these systems failed. Devised workarounds for several problems which extended the service life of some equipment for a number of years.

Corel Corporation	1999

Mandate: Extend the open-source Wine software to provide Win32 API routines required to implement a Linux port of Corel desktop applications. Provide technical support for the Corel Linux desktop software group.

Linux Application Software Development

Wrote a translator for DOS NMAKE and BAT files that allows scripts which normally build software on Windows to build the same software on Linux without modification.
Devised a simple regression test suite for Wine (known as "Drunkard"). Reports generated by the suite included automated image analysis and post-processed image display which detected changes in the visual appearance of GUI applications.
Designed and implemented a number of internal tools and processes for source code revision control and developer communication, including routine code merges with Corel's Wine development partners.
Reviewed code written by other developers at Corel.

IT Support

Implemented a gateway between external Wine mailing lists and internal NNTP servers, which was used by all of the Linux teams within Corel. The gateway was based on an open-source software package (sn) combined with custom Perl code for Corel. Fixed several bugs in the sn package (written in C), and contributed these fixes back to the author of sn, who accepted them gratefully.
Built and maintained Linux master server (providing servers for WWW, SMB, NFS, and CVS, as well as group data storage) for the Corel Draw Wine porting team.
Provided assistance to IT group when the behavior of certain Linux network drivers disrupted the corporate LAN. Some corporate procedures were adjusted to accomodate the problem behaviors without disruption.

Linux System Software Development

Built packages in Debian's packaging format (dpkg) for Corel's Linux distribution.
Solved various technical problems for the Linux distribution team in a number of areas related to the kernel and system setup.

Information Security

Audited Corel software for its Linux distribution. Discovered hundreds of instances of buffer overruns and insecure use of temporary files in the code. Determined the root cause for each of these instances and documented an approach to resolve each root cause. Recommended training for developers so that they could recognize and avoid such problems in future.

Open-Source Software Contributions	1993-present

http://www.hungrycats.org/~zblaxell/projects/projects.html

Open-source free software programs I have written or contributed to:

filereaper, a Perl script for real-time, secure, on-demand deletion of temporary files. Red Hat Software and Debian GNU/Linux used ideas from this script for their tmpwatch and tmpreaper utilities.
Contributed bug fixes for mgetty+sendfax, LPRng, quota utilities, and miscellaneous other packages to support Red Hat Linux systems.
Resolved dozens of bugs in the Debian Linux distribution by providing detailed bug reports, scripts to reproduce problems, technical analysis, or patches as required.
Contributed to the design of the interface renaming feature for Linux network firewalls implemented in Linux 2.1 to replace features removed during the transition from ipfwadm in Linux 2.0 to ipchains in Linux 2.1.
Contributed to design of /dev/vcs interface for Linux 1.2, while auditing security problems in the VGA console driver.
Fixed bugs in the Gravis Ultra Sound device driver for Linux using technical specifications downloaded from the chipset manufacturer's web site.
cddamp3, an application that converts audio CDs into MPEG Layer 3 compressed audio files using machines on a LAN in parallel. Includes a SCSI device driver for extracting CD digital audio data without D/A/A/D conversion and an algorithm that detects and compensates for incorrect data read from the CD-ROM drive. Implemented in Tcl and C++ for Linux.
mj, an application that schedules and plays MPEG Layer 3 files on Linux with cross-fade effects between files and automatic gain control to normalize volume levels. Written in C++ for Linux and Solaris with POSIX real-time extensions.
digitz, sound sampling software and device driver in Motorola 6809 assembler for OS-9.

Myrus Design	1995-1997

Mandate: Set up and maintain automated testing systems and source code revision control, port the software and verify consistent operation on all supported platforms, and create packages for end-user distribution; to perform internal IS functions ranging from end-user desktop support to security administration; and to operate the corporate Internet servers.

Linux Application Software Development

With other members of the development team, maintain and extend Myrus' flagship product: a CAD data translator and reporting system for industrial printed-circuit board (PCB) manufacturing users.
Designed cross-platform testing tools and automated testing procedures in Perl, Tcl/Tk, Bourne shell, C, and C++ on Solaris/Sparc, Solaris/X86, Linux, Windows 95 and NT.
Ported Myrus software from SunOS to Linux and Solaris and contributed to Windows 95/NT ports.
Researched several SCM systems including PRCS, CVS, and Aegis. Introduced CVS for source code management and designed procedures for developers to integrate code changes in a disciplined manner.
Increased corporate use of open-source tools and libraries to increase platform independence and software quality.
Developed prototype web-based CAD data translation server based on Myrus tools.

IT Support

Supported all computer users within the company (Linux, Solaris, Windows, Mac).
Developed a fax-to-WWW gateway, which allowed authorized users to view PDF files of incoming faxes, using standard Linux tools integrated with a 150-line CGI script.
Integrated Mac, Win95, and Unix printing and file sharing using standard Linux tools (LPD, netatalk, Samba).
Assembled, configured, and upgraded PC hardware used by Myrus.

Information Security

Wrote corporate security policy and installed firewalls and encryption tools to enforce it.
Designed and implemented a network firewall based on Linux code customized for extra paranoia.
Audited all software for use by external users on company servers for security purposes. Found a number of serious security problems and followed through to the vendor with analysis and fixes.
Developed WWW chat software for internal use (used by employees, suppliers, and clients) based on Linux, Perl, and Apache.
Implemented special-purpose customized servers, clients, and gateways for NNTP, HTTP, FTP, SMTP, and other protocols, to reduce costs, meet security requirements, or adapt to changes in technology and practice.
Frequent contributor to various technical interest groups and mailing lists on the Internet, including Internet, WWW, and Unix security groups.

Various Contracts	1993-1997

Built automated email-to-fax gateway software services based on Linux, Ghostscript, and Hylafax.
Developed firmware for an Intel 8051 microcontroller embedded in a satellite receiver system. Improved performance over previous firmware version by 300%. Started with zero knowledge of 8051 assembly language, completed project in less than 20 hours including all research time.
Installed and configured a Linux-based web server for a research group in the Waterloo science faculty.
Advised faculty of engineering staff fixing security problems on X11 terminals in a student engineering lab.
Security consultant for a small Ottawa software company. Rebuilt a web server that had been compromised by intruders and made several recommendations for system maintenance procedures to prevent a recurrence.
Administered Solaris and Linux machines and networks for the University of Waterloo Computer Science Club (volunteered, elected).

Awards

Chipworks "Top Metal" award for contributions to a software-controlled image acquisition system using a scanning electron microscope (SEM).
Member of 10th place team, 1994 ACM International Collegiate Programming Contest held in Nashville, Tennessee.
Member of 1st place team, 1994 ACM East Central Regional Programming Contest held at the University of Waterloo.
1st place, Spring 1994 Computer Science Club (CSC) programming contest at the University of Waterloo.
4th place, Fall 1993 CSC programming contest. Alternate team member for University of Waterloo team in the ACM regional programming contest.
Participated in "Shad Valley" business, computer, and science program in 1991.

Education

Completed 2A term (second year) of Bachelor of Mathematics/Computer Science (four year) program at the University of Waterloo.
Discovered I was not intended to become a mathematician.

Interests and Self-initiated Projects

Studied the internal implementation details of several open-source products:
- C++ compilers (GCC)
- Cryptography (SSL, GnuPG, CIPE, OpenVPN, Bruce Schnier's web site)
- Database systems (PostgreSQL, MySQL, Berkeley DB)
- Device driver implementation (Linux IDE, SCSI, FM radio, video capture, USB host controller devices)
- Image manipulation (Gimp, ImageMagick)
- P2P distribution and anonymity protection software (BitTorrent, gtk-gnutella, TOR, Freenet)
- Scripting language interpreters (Perl, Tcl)
- Spam filtering (SpamAssassin, DSPAM, CRM114, Razor, DCC, Paul Graham's web site)
- Video Capture (xawtv, BTTV, mplayer)
Maintain self-hosted Internet presence (Wiki, WWW, SMTP, spam filtering, DNS services, secure WiFi) at home with redundant DSL feeds (and yes, it is in my basement)
Developed a number of small applications designed for web browsers embedded in cell phones
Attended Ottawa Linux Symposium technical conference since 2000
Read technical blogs including Planet PostgreSQL, Linux Weekly News, comp.risks
Wrote Linux device driver for Aztech FM radio ISA card.
Implemented power-saving features (hard disk spin-down, monitor and printer power-off) in Microware OS-9 running on the Tandy Color Computer III by reverse-engineering and modifying the operating system binary code, designing power control hardware, and building it into the system motherboard.
Volunteer Audio/Visual technician (stage lighting and sound) at Gloucester High School.
Anime, cycling, photography, science, web comics