Sergiu B.
Sr. Software Engineer & Team Lead
Experience
Sep 2024 - Present
1 year 3 monthsChișinău, Moldova, Republic of
Sr. Software Engineer & Team Lead
We as Web
- Technologies: Ruby on Rails 5-7, PostgreSQL, JavaScript, Docker, AWS (EC2, S3, RDS, Lambdas, Route 53), Sidekiq, Redis
- Upgraded a large Rails application from legacy version to latest stable, increasing performance benchmarks by 35% and eliminating major security vulnerabilities
- Increased automated test coverage from 65% to 90%, which reduced deployment incidents by 50% and enabled a move to weekly release cycles
- Refactored background job processing and rake tasks, cutting job failure rates by 70% and reducing average incident recovery time from 3 hours to under 5 minutes
- Rewrote and optimized Docker configurations, shrinking local developer environment setup from 2 hours to 20 minutes and improving CI build reliability by 60%
- Standardized service-layer architecture, which decreased technical debt by 30% and accelerated new engineer onboarding by 0%
- Led modernization of 2+ legacy codebases, with zero production downtime during migrations
- Improved deployment tooling and workflows, reducing environment-related bugs by 80% and enabling faster rollbacks when issues occurred
May 2021 - Sep 2024
3 years 5 monthsChișinău, Moldova, Republic of
Sr. Software Engineer
Teamart Outsourcing
- Technologies: Ruby on Rails, OCR.space, RSpec, AWS, PostgreSQL, Sidekiq, Redis
- Developed and maintained document digitization features for the construction sector, enabling the automated processing of over 1,500 documents per day and reducing manual data entry by 80%
- Improved OCR accuracy by 30% through custom validation, helping to minimize data correction workload for end users
- Optimized backend processes, cutting average API response times by 5% and supporting a growing enterprise customer base
- Enhanced service reliability by improving Sidekiq job management and AWS S3 integrations, achieving 99.9% system uptime
Jun 2019 - May 2021
2 yearsChișinău, Moldova, Republic of
Sr. Software Engineer
Artsintez Media
- Technologies: Ruby on Rails, PostgreSQL, RSpec, Sidekiq, Redis
- Developed and maintained document management systems for two state institutions, digitizing and organizing over 100,000 official records
- Built and launched a public website for ASEM, integrating a payment API to enable secure online transactions for 10,000+ users
- Created user feedback and admin modules that improved daily workflows for staff at several client companies
Sep 2018 - Jul 2019
11 monthsChișinău, Moldova, Republic of
Software Engineer
Academy of Economic Studies of Moldova (ASEM)
- Technologies: Ruby on Rails, PostgreSQL, RSpec, Sidekiq, Redis
- Developed and supported internal correspondence and monitoring applications used daily by 500+ staff and students
- Automated IT workflows and routine tasks, reducing manual intervention by over 60% and improving overall system reliability
- Built command-line and web tools to simplify network monitoring and maintenance, decreasing response times to technical issues by 0%
Jul 2017 - Mar 2018
9 monthsKyiv, Ukraine
Software Engineer
Bitsane
- Technologies: Ruby on Rails, Blockchain (wallet automation), RSpec, Sidekiq, Redis, REST API
- Developed core account management logic for a cryptocurrency trading platform serving over 50,000 users
- Implemented automated wallet creation and removal, reducing manual onboarding steps by 90% and improving transaction reliability
- Integrated the Advanced Cash payment API, enabling seamless deposits and withdrawals for users and supporting increased trading volumes
Jul 2015 - Nov 2017
2 years 5 monthsChișinău, Moldova, Republic of
Software Engineer
Obmen.md
- Technologies: PHP, SOAP, MySQL, Ubuntu, NGINX
- Sole developer responsible for designing, building, and launching a real-time online currency exchange platform used by over 3,000 registered users
- Developed and maintained all core logic, including automated rate parsing (reducing manual updates to zero), secure payment integrations, transaction workflows, and system APIs
- Led all testing (with 90%+ code coverage), deployment, and post-launch support activities, ensuring 99.9% uptime and smooth daily operations processing 100+ transactions per day
May 2013 - Mar 2015
1 year 11 monthsKyiv, Ukraine
Software Engineer
LLC IPS RISE
- Technologies: PHP, SOAP, MySQL, GIT, Ubuntu
- Designed and developed payment gateway APIs and transaction processing systems supporting 10,000+ daily transactions
- Led the technical integration of payment solutions for multiple partner companies, accelerating project delivery by 30%
- Collaborated with cross-functional teams to ensure system stability and security, reducing payment-related support tickets by 25%
Nov 2006 - Apr 2010
3 years 6 monthsChișinău, Moldova, Republic of
Project Manager
MahjongTime
- Technologies: Internal QA tools, Bug tracking, MS Office Suite, Redmine
- Managed stakeholder communication, feature planning, and project documentation
- Coordinated QA and bug tracking activities between development and support teams
- Helped launch new features and supported basic marketing efforts
Summary
Results-driven software engineer with 15+ years of experience in backend and cloud systems, specializing in Ruby on Rails, PostgreSQL, Docker, AWS, and Sidekiq/Redis. Proven track record in system modernization, performance tuning, background job optimization, CI/CD automation, and secure API development. Skilled at scaling distributed applications, integrating payment gateways, and improving developer productivity through modern DevOps practices. Adept at collaborating with cross-functional teams to deliver reliable, high-performance, product-driven solutions.
Languages
English
AdvancedRomanian
AdvancedRussian
AdvancedEducation
Oct 2020 - Jun 2023
Academy of Economic Studies of Moldova
Bachelor's Degree · Applied Informatics · Chișinău, Moldova, Republic of
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