Tomas Jacik

Linux administrator, web developer, and consultant

Tomas Jacik
Based in: Czech Republic Czechia Working area: global
Status: at your service Languages: English, Czech
Listed in: Development & Tech

I bring reliability to IT, helping my customers with web applications and server problems. I always look for a solution that eliminates the core of a problem, not only its consequences:

  • Boosting performance — Is your eshop or server too slow? I can move it to a much faster dedicated server.
  • Speeding up applications — The loading speed of websites and ecommerce apps is all-important. I will make them run much faster by tweaking OS and services like Apache, nginx, MySQL, PostgreSQL, etc.
  • Optimization of older apps — Legacy code is a root of many problems. I can review your old app or eshop to extend its lifespan, while also cutting some technical debt. In ecommerce, I have a lot of experience with open-source solutions (PrestaShop, ZenCart).
  • Security improvements — Everyone feels safe, until they’re hacked. I help my clients to prevent countless risks by proactively improving their IT security.
  • Complete server management — I can take care of your web and application servers, so that they are always fast, secure, backed up and running as smoothly as expected.

I am a reliable partner under any circumstances including critical situations, and a strong advocate for the reliability of all IT experts — as a norm, rather than an exception. That is why I am trusted by big players like Footshop, one of the major shoe sellers in Europe.


  • Programming — I have deep knowledge of PHP and Python. I have also written some code in C, C++, JavaScript and Ruby. I am well informed about unfamiliar code and I’m not afraid of legacy code. I prefer programming in Nette Framework, mostly using components from Symphony. I strive to write quality, safe and testable code.
  • Servers — I mastered operating system administration based on Linux, BSD and Solaris. I can set and speed optimize the service settings of Apache, nginx, PHP and MySQL. I also administer and work with PostgreSQL. And I run my own VPS hosting using SmartOS.
  • Web servers and databases — Apache, nginx, MySQL, PostgreSQL, Redis, RabbitMQ, ElasticSearch
  • Virtualization — KVM, Smart OS, Danube Cloud, Docker
  • OS – Debian / Ubuntu, FreeBSD / Open BSD, Solaris
  • Automatization — Ansible

What I do (including examples)

  • Speed optimization
    • I accelerated the loading speed of eshop from several dozen of seconds to hundreds of milliseconds without seriously interfering in the code by installing and optimizing new server settings. I optimized the settings of Apache, PHP and MySQL services and installed monitoring via NewRelic.
    • I accelerated the loading of eshop from several dozen of seconds to dozens of milliseconds by rewriting key parts of the PrestaShop open source solution. I optimized SQL database queries, adjusted the indexes of MySQL tables and installed full-text search using Sphinx.
  • Servers
    • For my clients, I have installed Linux servers or VPS, where their applications run now. I tailor-made the configuration of services like Apache, nginx, PHP and MySQL so their applications run as fast and safe as possible.
    • I continually manage some of my clients’ servers or VPS. I supervise their updating and safety. I go over logs to check whether something wrong is happening and adjust their service settings based on their actual needs.
  • App development
    • I programmed a complete backend, including the customer section and administration, for the website The graphics and templates were provided by the agency, which I have cooperated with on other projects too.
    • I was one of the programmers that developed the internal business system for Seznam, the biggest Czech internet company. I have also worked on other projects for Seznam, including Sreality and Zbozi.
    • I created a new customer portal for the affiliate network I also develop a new transaction tracking solution for eHUB.
    • I programmed the product filters by motorcycle parameters for eshop.
  • Refactoring — I am not scared of legacy code and I’m not afraid to interfere with it. I successfully applied new designs to old eshops based on ZenCart like or
  • Open source — I contribute to open-source projects and develop new libraries. I am active in the Nette community. You can see my code on Github under the nicknames sunfoxcz and foxycode.
  • Communication — I am an altered introvert. Running a business taught me not to be afraid to speak with people and to solve problems once they appear. You can rely on me to actively communicate with you and inform you about all the obstacles.
  • Data conversion
    • I wrote the scripts for the complete transfer of several eshop databases from ZenCart-based to PrestaShop-based solutions for eshop and others. I created the scripts for the export of orders to the accounting system Pohoda.
    • I developed a bridge for the synchronization of campaigns from MailChimp to Percolate using the API of both platforms. The bridge is programmed in Python language and runs on Google App Engine.
  • What I don’t do:
    • Front-end development — Although I know HTML, CSS and JavaScript, today’s front-end development is not based on these cornerstones only. It’s essential to know the differences between the browsers. To know how to make a webpage responsive. There are more competent experts for this.
    • The development of new features for PrestaShop — After years of experience with this ecommerce solution, it is my opinion that in the long term, one cannot build a working business on it. Don’t get me wrong. PrestaShop is perhaps the best available opensource solution. But it has become a victim of having too many functions, trying to satisfy everyone. In the end, the code is too difficult, the architecture is wrongly projected and the development of new functions too time consuming. It is very difficult to make some bigger adjustments without breaking some part of the shop.
Tomas Jacik

Contact details

Tomas Jacik
Sunfox s.r.o.
Vodnanska 1414
198 00
Czech Republic, European Union
Mobile:+420 606 053 606
VAT ID:CZ28436296

Firsthand recommendations

Mr Jacík helped us with the speed of our eshop, which had been very poor. After Mr Jacík’s intervention, we have a website users can use without any problems again and the speed of the website bothers neither us in the backoffice nor the customers. We cooperate with him on the development of the website on a regular basis and I must emphasize his reaction time to questions and requests, which is definitely much shorter than the average in this profession and that lightens subsequent work a lot. Generally, I can only recommend him. We will continue with our cooperation.

Vaclav Vana operations manager at Footshop

Tomas is a developer and an analyst with inquisitive questions that customers tend to forget so often. Because he sees beyond the terms of contracts, he is a very welcome co-developer in the team work.

Petr Sykora developer and analyst at

Tomas has always been able to solve problems unsolvable for others. He is not only a great programmer, he understands the issues of servers in particular.

Zdenek Koutny representative of Koutny Software s.r.o.
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