Sergii

Sergii Panichev

Country: Poland
City: Krakow
Mobile: [open contact info](look above in the "contact info" section)
Email: [open contact info](look above in the "contact info" section)

Summary
A Software Engineer with experience across multiple industry sectors: Financial,
Health, Security, Large Analytical Systems, CRM, ERP, B2C, and B2B web-services,
covering a wide range of companies from small start-ups to large Enterprise
Corporations.

Working with the wide range of technologies such as PHP, Java, JavaScript, React,
Vue, Amazon Web Services, Google Cloud Services, relational and no-relational
Databases, and related open-source technologies. Proficient in aspects of the
software development lifecycle, Scrum and Agile methodologies, Continuous
Integration and Continuous Delivery services.

I’m a very motivated person, with a strong orientation to achieve goals. I can work
in a team or as an independent person. This makes me able to completely support
the whole app, process and coordinate a team. I have a sense of organization,
accuracy, and punctuality.

Technical skills
• Object-oriented programming, SOLID, TTD, DDD, MVC, Design Patterns, etc.
• PHP (Laravel, Symfony)
• Java (SpringBoot)
• Javascript (React, Vue)
• Database design and management (Mysql, Postgresql, Redis, MongoDB)
• RESTful web-services (JSON, SOAP, oAuth2, JWT)
• Queue and message brokers (RabbitMQ, Kafka)
• Cloud services (Google Cloud, Amazon AWS)
• Microservice architecture design and management
• CI/CD tools (Jenkins, GitHub Actions)

Education
Sept 2000 - Jul 2005 National Aviation University
Master’s degree in computer science.
May 2014 - Dec 2014
Data structures and Algorithms.

Sept 2018 – Oct 2019
Java Advanced Programming course

Work experience
Sep 2020 - May 2026, Defentry AB, Software Engineer / Team Lead &
Architect
Defentry is a proactive Cyber-Safety SaaS platform designed to protect digital
identities through real-time data breach monitoring and credential leakage
detection. The system scans the surface, deep, and dark web to identify
compromised personal data, providing automated alerts and remediation steps to
help users mitigate the risk of identity theft and account takeovers.
Tech Stack: PHP8.2+, Java, Laravel, RabbitMQ, MySQL, Google Cloud, Redis, React,
ReactNative

• Engineered and architected migration from monolith to micro-services
• Implemented internal engineering policies
• Implemented CI/CD pipelines
• Developed and integrated a wide range of product’s features
• Led a tech team of 6 ppl
• Implemented Event Driven Architecture
• Worked closely with company customers and provided technical assistance
• Implemented RabbitMQ queues for internal notification service sending around
100k SMS, Email and Push notifications daily
• Implemented Exponential Backoffs and Circuit Breaker patterns
• Engineered processing billions of leaked users records and matching them against
internal user’s database
• Worked closely with Product Owners and Management Team
• Implemented different statistical dashboards

Dec 2017 – Jul 2020, KRY AB, Senior Software Engineer
KRY is a market-leading HealthTech platform that revolutionizes patient care
through digital-first primary healthcare services. The ecosystem connects millions
of patients with healthcare professionals via secure video consultations, integrated
electronic health records (EHR), and automated prescription management,
streamlining the entire medical journey from diagnosis to recovery.
Tech Stack: Java, PHP, MySQL, PostgreSQL, Redis, AWS, MQTT, Kafka, React
• Worked with internal appointments and notifications system
• Worked with Legacy stack
• Implemented several internal services using PHP, Java and React
• Engineered and implemented integration Laravel framework in legacy PHP project
• Engineered and implemented migration from On-Premise solution to AWS Cloud
with multi-tenant architecture.
• Worked on bug fixes in backend and UI (front-end)
• Worked on development new features

Dec 2016 – Jul 2017, Onlyfans, Senior Software Engineer
Onlyfans is a global social content platform serving 100M+ users daily. I worked as
a Software Engineer and performed wide range of engineering tasks, such as: new
features development, testing, database optimization, etc.
Tech Stack: PHP, PostgreSQL, Redis, AWS, VueJs

• Worked on database optimization for large datasets
• Worked on migration legacy stack to modern frameworks
• Worked on bug fixes
• Worked on development new features
• Created a dedicated environment for performing auto-tests with dedicated API
endpoints.

May 2013 – Sep 2016, Ciklum LLC, Senior Software Engineer
Ciklum is a Danish world-wide outsourcing company. During that period I
participated in several projects of EU companies as a Senior Software Engineer and
as a Frontend developer.
There were as big companies with more than 300 employers and as small
companies.
I developed different kinds of projects (e-Commerce, financial, payment gateway,
API services for mobile applications, etc.).
Tech Stack: PHP (Symfony/Laravel), MySQL, PostgreSQL, Redis, AWS

• Worked as a full stack engineer outsourced to different clients/projects
• Worked on developing bug fixes and new features
• Developed RESTful APIs and stateful (session based) backends

Feb 2008 – Apr 2013, Eurolab LLC, Software Engineer.
A specialized Healthcare Information System (HIS) designed to manage the end-to-
end operations of a premium multidisciplinary clinic. The platform digitizes the
patient journey from initial booking and digital triaging to internal medical record
management and automated billing, ensuring a seamless flow of data between
patients, clinical staff, and administrative teams.
Tech Stack: PHP (Symfony/Laravel), MySQL, Redis

• Worked on development internal medical systems
• Integrated Laboratory software with existing products
• Developed client’s personal account
• Developed internal appointment system
• Worked on Genetic Passport project
• Developed internal system for accounting and analyzing payed checks
• Developed online video consultation tool
• Developed a former medical portal eurolab.ua from scratch

Languages
Ukrainian - Native
Russian - Native
English – Upper-Intermediate (B2)