Sergey Efremov Email and Phone Number

Main tasks: - Developed and supported integration architecture. Controlled new systems integration. - Analyzed business cases and developed network and application architecture of IT systems. - Created HLD (High Level Design) of developing systems. - Created technical specifications based on user stories. - Took part in product management.Achievements:- Created the architecture of a solution for the B2B segment, which allows for the collection of data and calculation of premiums for each employer of each regional IT landscape (including 8 billing systems and 8 CRM systems).- Improved the documentation process.

Prior tasks: - Researched the architecture of mobile devices, such as automobile GSM terminals, animal sensors and metering devices (water and electric meters).- Developed architecture of collecting, validating and processing data from M2M meters, including architecture of mircoservices and database tasks. - Created technical documentation and ensured it's compliance.Achievements:- Organised the process of creating documentation in Confluence, including the structure of sections and requirements for each type of document and section. - Gained a significant experience in the M2M/IoT segment.- Aqiured experience in developing multy layers architecture, including dividing getting, processing and using data from mobile devices

Main tasks:- Had organized processes of 2nd line support of a hight load government system, based on IT based on ITIL standards. - Was analyzing architecture of high load systems. - Optimized network and clusters architecture, implemented common system of collecting and storing logs (kibana. Elastic searh)- Implemented common system of monitoring and set common reglament of notifications- Implemented common process of software release processesAchievements:- Created and implemented regulations of monitoring (adding new systems to process of monitoring and notifications for 24x7) - Achieved Indicator of 100% service availability 24x7- Implemented WebLogic BalanceOver cluster, OracleDB multi-master cluster, MariaDB with Galera Cluster (multi-master).- Organized system of web request balancing (more than 300 rps), implemented cache over web requests (based on nginx)

I have been a developers team leader.- Developed network and system architecture according to business needs. Including reserv and standby servers.- Collaborated with clients to determine project specifications and scope.- Engineered architecture of web application with 10 000 users (clients, sales and managers).- Improved business productivity for clients by by re-engineering and designing technical process for 2ltp. - Provided technical leadership to team members during system design.- Provided current best practices and third-party solution alternatives when necessary for functional design documentation. All documentation were moved to online resources (Confluense). And CI/DI process was integrated with jira. - Monitored and tested application performance to identify potential bottlenecks, develop solutions and collaborate with developers on solution implementation.

Main tasks:- Was coordinating work of IT Departments - Was an IT leader in software development- Was creating IT architecture of company it landscape- Was coordinating communications with marketing department - Was coordinating SEO - Took part in documentation Achievements :- Has been implemented a unified software development mechanism.- Has been created a multilevel data processing model including: caching of data by types: user requests and objects (the cache is forced to be updated when changes are made in the system).- Has been created a mechanism for standard subscriptions (the subscription is formed in the form of text files to reduce the load on the application server)

Main tasks:- Conduced system analysis- Developed software: PHP 3, MySql, Oracle DB, Java Portlets, MsSql, ASP.Achievements :- Created own ORM framework than allowed to change software more quick. - Created mechanism for importing different objects by automatic parsing xml data - The analysis of the structure was carried out, the IDEF models "AS IS" and "TO BE" were formed, in compliance with the principles and GOST (GOST 34).