Denis Zhukov, Developer in Tel Aviv-Yafo, Israel
Denis is available for hire
Hire Denis

Denis Zhukov

Verified Expert  in Engineering

Software Developer

Location
Tel Aviv-Yafo, Israel
Toptal Member Since
December 7, 2015

Denis has been working as a *nix (Linux, FreeBSD) system administrator and DevOps engineer since 2003. Coding recently mostly in Python, Groovy, and Bash Scripting. He has experience configuring and working with different types of server software and technologies, such as containerization, databases, web servers, mail servers, DNS servers, virtualization, firewalls, and Big Data.

System AdministrationLinuxDebian LinuxBashMySQLNagiosZabbixPuppet.jsSQLWindowsPostgreSQLSubversion (SVN)FreeBSDMongoDBHadoopXen HypervisorLotus DominoPleskRadiusJFrog Artifactory

Portfolio

Citigroup
Bash, Linux, RHEL, OpenShift, Artifactory, Jenkins, Java, Groovy, Docker...
Spaceweb/Hosting Community/RU-CENTER Group
Bash, BIND9, BIND 9, Xen, PostgreSQL, MySQL, PHP, Apache, NGINX, Gentoo, Linux
Sicres Telecom
Bash, Asterisk, VoIP, Cisco, Windows, FreeBSD, Linux, RouterOS, MikroTik

Experience

Linux - 15 yearsBash - 15 yearsMySQL - 15 yearsXen - 8 yearsPostgreSQL - 8 yearsFreeBSD - 3 yearsPuppet.js - 3 yearsHadoop - 2 years

Availability

Part-time

Preferred Environment

Amazon Web Services (AWS), Jenkins, Infrastructure as Code (IaC), Groovy, Python, GitLab CI/CD, Kubernetes, Docker, Linux

The most amazing...

...thing about my job is preventing DDoS attacks and working with high-load projects.

Work Experience

DevOps Engineer

2017 - PRESENT
Citigroup
  • Engineered solutions for a high-availability, enterprise-wide binary repository based on JFrog Artifactory, including all sorts of troubleshooting and maintenance work.
  • Created, troubleshot, and documented best-practice CI/CD processes for tens of thousands of Citi developers, in partnership with Jenkins and TeamCity build teams.
  • Wrote, as part of the development team, a software system providing developers self-service capabilities to create projects and complete CI/CD pipelines based on OpenShift, Tekton, and Harness while integrating many other Citi internal services.
  • Mentored new team members and documented all aspects of teamwork. Implemented SRE practices for toil elimination, post-mortem analysis, etc.
Technologies: Bash, Linux, RHEL, OpenShift, Artifactory, Jenkins, Java, Groovy, Docker, Ansible

System Administrator

2007 - 2014
Spaceweb/Hosting Community/RU-CENTER Group
  • Contributed to a project focused on developing or introducing new technological solutions.
  • Installed, configured, and maintained a large number of web hosting and infrastructure servers running Linux/FreeBSD.
  • Contributed to technical and administrative reorganization.
  • Developed, implemented, and commissioned parts of a commercial solution in the field of virtualization based on Xen.
  • Provided solicitations to software configuration problems on servers and initial diagnosis of equipment problems.
  • Constantly monitored all services.
Technologies: Bash, BIND9, BIND 9, Xen, PostgreSQL, MySQL, PHP, Apache, NGINX, Gentoo, Linux

System Administrator

2006 - 2007
Sicres Telecom
  • Administrated servers running Mikrotik RouterOS/Linux/FreeBSD/Windows.
  • Prepared and commissioned wireless complex Alvarion WALKair-1000 operating at frequencies of 10.5 GHz, covering about 90% of the Kishinev area.
  • Utilized communication/radio relay/DSL/VoIP equipment from Cisco, SAF, ZyXEL, RAD, AudioCodes, and Quintum.
  • Reorganized company infrastructure with insulation of individual networks to improve the security and reliability.
Technologies: Bash, Asterisk, VoIP, Cisco, Windows, FreeBSD, Linux, RouterOS, MikroTik

System Administrator/Technical Support Operator

2005 - 2006
StarNet
  • Provided end-user support and solved technical problems.
  • Configured ADSL/WiFi equipment (ZyXEL, Dynamode, Huawei, Asotel-Dynamix, D-link, C-COM, Kobishi, Intel, ZTE, Ericsson).
  • Used Ericsson Public Ethernet Manager and servers running Mikrotik RouterOS/FreeBSD/Linux/Windows.
Technologies: RouterOS, MikroTik, ADSL, FreeBSD, Windows, Linux, Ethernet

System Administrator

2004 - 2005
IATP Moldova/IREX project
  • Supported and improved organizational technical structure (Windows and Linux servers used for web hosting, e-mail services, and gateways; lots of user workstations in 8 IATP Centers around Moldova), solving hardware and software problems.
  • Migrated working mail and accounts from legacy Sendmail system to a fully-functional secure mail system using Qmail, Vpopmail, ClamAV, and SpamAssassin.
  • Supported user sites, FTP accounts, and mail for IATP Moldova program.
Technologies: FTP, Bash, IIS, Azure Active Directory, Microsoft SQL Server, SpamAssassin, ClamAV, Qmail, Linux, Windows

System Administrator

2003 - 2004
MoldInfoNet
  • Installed, configured, and administrated local and remote FreeBSD/Linux/Windows servers.
  • Configured leased lines connections using Zyxel and Dynamix equipment.
  • Configured and supported a large Moldavian governmental network.
  • Used Cisco equipment.
Technologies: Plesk, Hosting, Multi Router Traffic Grapher (MRTG), IMAP, HTTPS, HTTP, Bash, Lotus Domino, RADIUS, Squid, NAT, FTP, POP3, SpamAssassin, SMTP, PostgreSQL, MySQL, DNS, Windows, Linux, FreeBSD

Simple Deployment System for Spaceweb

A simple deployment system that I made while working for one of my previous employers. As per company policy, we didn't deploy any internal software with Puppet, only standard software. Thus, I wrote the script myself. My goal was to allow an administrator to install the operating system to a server, assign some role to it, and then run the script. The script connected to a database, received the server's role from its hostname, deployed all the software projects for that role, and ran some additional commands mentioned in the database if necessary.

The whole system consisted of one bash script and several tables in MySQL, but it still made our life much easier. As far as I know, it is still in use.
1999 - 2003

Specialist's Degree in Informational Technologies

State University of Moldova - Moldova, Kishinev

Libraries/APIs

Puppet.js, RADIUS

Tools

Nagios, Zabbix, NGINX, SpamAssassin, Squid, Lotus Domino, Plesk, ClamAV, Asterisk, Apache, GitLab CI/CD, Jenkins, Cloudera, Vagrant, Git, Subversion (SVN), Artifactory, Ansible

Languages

Bash, PHP, Python, Groovy, SQL, Java

Platforms

Debian Linux, CentOS, Linux, Xen, Docker, RouterOS, Amazon Web Services (AWS), Kubernetes, Windows, FreeBSD, KVM, Android, OpenShift

Paradigms

Hosting

Storage

MySQL, Microsoft SQL Server, Azure Active Directory, MongoDB, PostgreSQL

Frameworks

Hadoop

Other

System Administration, Linux Administration, Ethernet, ADSL, MikroTik, DNS, SMTP, POP3, FTP, NAT, HTTP, HTTPS, IMAP, Multi Router Traffic Grapher (MRTG), Qmail, IIS, Cisco, VoIP, Gentoo, BIND 9, BIND9, Infrastructure as Code (IaC), Information Technology, RHEL

Collaboration That Works

How to Work with Toptal

Toptal matches you directly with global industry experts from our network in hours—not weeks or months.

1

Share your needs

Discuss your requirements and refine your scope in a call with a Toptal domain expert.
2

Choose your talent

Get a short list of expertly matched talent within 24 hours to review, interview, and choose from.
3

Start your risk-free talent trial

Work with your chosen talent on a trial basis for up to two weeks. Pay only if you decide to hire them.

Top talent is in high demand.

Start hiring