Sergii Iakymenko

Experience

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  Factorial Bank

  Aug 2007 - Mar 2009

  Software developer

  Worked on the application to calculate liquidity, rates, score and get the loaner's class. This class was used by an Account Department to make a further decision.• Designed database structure.• Implemented business logic and financial engine.• Implemented user authentication and authorization module.

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  SEB

  Mar 2009 - Mar 2010

  Software developer

  Worked on the design, implementation & support of internal billing system for corporate mobile phones. Main features: searching information in the database, showing results in a multifunctional grid (pageable view, sortable columns, editable cells, etc.), upload billing statements, reporting system, creating documents for corporate financial system (account department), data export (Excel, XML).• Designed database & implemented business logic. • Designed user interface with GWT technology. • Implemented user authentication and authorization module. Show less

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  EPAM Systems

  Mar 2010 - Apr 2019

  Work on requirement gathering, architecture & design, implementation and support of API gateway ecosystem. Technical lead and a key contributor for onsite team of 7 talented engineers. Directly lead an offshore team of 4 people, established communication between two teams in different timezones. Develop DevOps practices in AWS Cloud. Mentor & an active interviewer.• Led initiative to define selection criteria to choose 3rd party product. Analyzed requirements, performed research & made a final decision of the product.• Established DevOps best practices within the team: security, infrastructure as code, governance, containerization.• Led effort to fully automate development processes. It now takes about 20 mins to deliver the change to production system comparing to 10 hours of manual work. Show less Designed and implemented global authentication and authorization REST service for payment systems based on IETF standard - MAC Access Authentication & OAuth2.0. Developed project delivery plans, capacity planning, performance testing etc.• Established and improved team development processes to setup the team for high quality and effective delivery. Improved code review turnaround time from week to one day with increased quality of CR feedback.• Reduced functional tests execution time in 30 times. Show less

  • Lead Software Engineer (Expedia)

    Nov 2015 - Apr 2019

  • Senior Java Developer (Expedia, Copyright Clearance Center)

    Mar 2010 - Oct 2015
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  Luxoft

  Nov 2015 - Jun 2016

  Senior Software Engineer (UBS Bank)

  Worked on design, implementation, CI/CD & support of web-based application for bank products classification. Played key role in refactoring legacy parts of the system. Improved various Agile processes with positive results on team performance.• Established CI/CD using Teamcity: one-click-deployment to DEV/UAT environments, adopted Sonar, automated dependency resolving and releasing strategies, integrated automated tests into deployment pipeline.• Introduced extreme programming practices to the team, organized code review process. Show less

• 

  T-Mobile

  Apr 2019 - Nov 2021

  Principal Software Engineer

  Developed a highly available and resilient Payments Platform along with PaymentsGateway, Wallet, Tokenization, Encryption, and many other payments products. - Led, designed & implemented initiative to make the platform resilient, highly availableand fault tolerant in a hybrid environment (OnPrem + Cloud) to process billionsrequests per day. Created numerous HLDs & LLDs.- Established DevOps best practices within the team: security, infrastructure as code,governance, containerization.- Led the effort to fully migrate 300+ repos from the legacy CI/CD platform to GitLab.Designed & implemented e2e SDLC process from scratch considering all the bestpractices. Exposed common templates used by many teams across T-Mobile. -Designed and implemented configuration management framework used by allmicroservices within Payments Ecosystem.- As a hiring committee member worked on the framework to standardize an SDEhiring process: technical, behavioral interviews, reporting, estimation, decisionmaking, etc.) for the entire company. That allowed us to scale up the interviewingprocess and increase hiring by 200%. Show less

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  Smartsheet

  Nov 2021 - Mar 2024

  Principal Software Engineer
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  Hims & hers

  Jun 2024 - now

  Principal Software Engineer