Denis Efimov Email & Phone Number

Eindhoven, North Brabant, Netherlands

Eindhoven, North Brabant Province, Netherlands

I am working on the backend of the X2-Series Network Packet Brokers which allow our clients to enhance the performance of their analysis and security tools. Profitap Network Packet Brokers are designed for aggregation, filtering, and routing of multiple 1/10/25/40/100G inputs, used in high sustained bandwidth port monitoring and analysis scenarios.• moved the codebase to multithreading which allowed to improve significantly the overall user experience and the system response.• developed local authentication system using JWT and support for Tacacs and Radius authentications.• made a checking mechanism (compile-time) of features compatibility. This allowed to prevent that sort of issues completely.• implemented SNMP submodule and NTP clock synchronization feature satisfying the needs of our customers.• worked on improvements of our CI pipeline integrating valgrind code checks. That helped us to find and fix potential problems.

Minsk, Belarus

I worked for an international game developer and publisher, and was a part of a huge mobile department as well as a member of a small productive team. As a team in an agile environment, we decomposed, planned, and produced new features every two or three sprints. Here we were focused not only on technical skills but team inner interactions and interactions with other teams in the department.Our general goal was developing, maintaining, and improving the World of Tanks Blitz game client which required a wide spectrum of skills and knowledge.• Designed, coded, implemented and tested new features for the game client as part of an Agile team.• Analyzed and resolved memory leaks and performance issues using the VS profiler.• Debugged and fixed many bugs decreasing technical debt.

I was involved in developing the “Tribez & Castlez” application as a UI and gameplay developer for the world’s leading innovator in mobile and social games. The project has given me the experience to balance decisions between the best in perspective and the quickest in realization. The most important part of my work included a wide variety of tasks from bug fixing to developing huge features like actions and events. Using the whole power of Visual Studio IDE and its very useful set of tools, I had a good control of the code and I did my job efficiently and with high quality. Being enthusiastic over fundamental knowledge such as algorithms and design patterns, I also could not allow myself to overlook new things, such as C++11 features, and I always tried to apply additional skills in my job wherever possible.

As the company had a successful Internet site-blocking system designed for large Internet providers, it was necessary for the company to also develop a solution for smaller Internet providers as their simpler hardware prevented them from using the original system. Being the sole worker on the project, I was responsible for the conception, architecture and realization of a prototype system designed to fix the problem. The work was full of experiments and involved real experience time by making a huge amount of different everyday decisions, such as how to glue session messages together more efficiently and figuring out the quickest way to parse URLs from them. As a result, I successfully developed a prototype system using only one router with mirroring the outgoing traffic and using TCP reset attacks and fake server answers in order to block access to a forbidden site.

This position allowed me to demonstrate my problem solving, communication and organizing skills. Being the only person on-site in some of the projects, I fully controlled the development, testing and releasing processes.Two of the projects involved bug fixing and improving bank program systems which were created more than 10 years ago using VC++ 6.0 and which lacked software documentation. As a result, it was a challenge to come to know the particulars of the software and to solve all tasks perfectly and within the scheduled deadlines.The project I liked the most consisted of investigating customer’s requirements and developing a prototype system. It was necessary to know whether it was possible to create a wireless digital video translational system for a special service which might work in an environment with huge radio noise levels with up to 10% of data. Taking an active part in developing the prototype which consisted of an encoder, a noise generator and a decoder, I also studied a lot about noise-resistant coding algorithms and their efficiency. In general they were C++, Qt, Git and different open-source noise-resistant coding libraries used by me.

I took part in a multi-team project which focused on developing a software/hardware complex which involved the collecting, the long-term storing, and the processing of activity data belonging to cellphone subscribers, such as calls, messages, locations and internet activity during a period of at least 3 years.The key responsibilities of the role included supporting the existing C++ code and developing new features such as text/binary files parsers, extending the program logic for its flexibility improvement, and coding a lot of various shell scripts.