Sergei Radchenko
Senior Software Engineer at Dun & Bradstreet
Tallinn, Harju County, Estonia
Summary
👤
Senior🎓
Top SchoolSergei Radchenko is a seasoned senior software engineer based in Tallinn with over 16 years of professional experience and more than 20 years building web applications end-to-end. He blends full-stack development (Symfony, Node) with system design, infrastructure hardening, data extraction and analysis, and hands-on security testing—often wearing the architect, devops and UX hats on the same project. As owner of BlackCrystal Ltd. and a long-term contributor to enterprise data systems (Dun & Bradstreet, Bisnode), he delivers practical, production-grade solutions that emphasize reliability, SEO and measurable UX improvements. Comfortable with legacy and modern stacks alike, he also has a background in prepress and hardware maintenance, which gives him an uncommon appreciation for operational resilience and attention to detail. His personal motto, “Show what you can. Learn what you don’t,” reflects a pragmatic, continuous-learning approach to solving complex web and data problems.
15 years of coding experience
13 years of employment as a software developer
Show what you can. Learn what you don't., Show what you can. Learn what you don't. at School of LifeTallinna Kopli Ehituskool
Russian, English, Ukrainian, php
Stackoverflow
1reputation
0reached
0answers
0questions
Github Skills (64)
converter9
doctrine9
telegram-bot9
php9
telegram9
swiftmailer9
blockchain8
ton8
commonmark8
cryptocurrency8
mapper8
markdown8
relational8
bundle7
symfony7
Programming languages (6)
Github contributions (5)
BlackCrystal/symfony1
Jun 2021 - Feb 2024
Fork of symfony 1.4 with DIC, form enhancements, latest Swiftmailer, better performance, composer compatible and PHP 7.0 support
Contributions:8 PRs, 9 pushes, 1 branch in 2 years 8 months
better-performancemailerphpsymfony-bundledic
miamibc/joker-telegram-bot
Jul 2019 - Dec 2022
Telegram bot made with PHP to be simple and fun
Contributions:7 releases, 418 commits, 113 PRs in 3 years 5 months
telegramtelegram-botbotphp
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