Stepan Tanaka - Senior Software Engineer

Bucharest, Romania

Experience

Jun 2022 - Present

3 years 8 months

United Kingdom

Senior Software Engineer

Atos

Led the design and development of enterprise-level applications integrating Ruby backend modules and Python-based AI model evaluation pipelines, handling over 1 million daily transactions efficiently with automated CI/CD workflows.
Implemented robust CI/CD pipelines using GitHub Actions and Jenkins, ensuring smooth deployment and testing for complex AI-driven features within Atos’ hybrid cloud environment.
Developed containerized Ruby and Python microservices using Docker and Kubernetes, supporting high-performance data annotation and AI training workloads across multiple teams.
Collaborated with solution engineers and AI project leads to benchmark LLM models in sandboxed environments, producing reliable evaluation metrics for strategic deployment.
Reviewed, refactored, and improved legacy Ruby codebases, identifying anti-patterns and code smells, and implementing automated tests to secure quality across Atos enterprise applications.
Authored high-quality documentation for test cases, AI model evaluation reports, and technical processes, ensuring clear knowledge transfer within distributed teams.
Guided junior engineers on Ruby metaprogramming techniques and idiomatic practices, improving team capability in AI-enabled system integration projects.
Implemented multi-language support modules (JavaScript/TypeScript, Rust) to interface with LLM training scripts, achieving seamless cross-language execution for AI pipelines.
Monitored production systems and debugged complex issues in Linux and cloud-based environments, improving system reliability during large-scale AI and enterprise application operations.

Sep 2016 - May 2022

5 years 9 months

Romania

Software Engineer

EXE Software

Developed and maintained Ruby-based backend systems and RESTful APIs for financial and healthcare applications, processing over 500,000 records daily while maintaining robust security and compliance standards.
Implemented automated CI/CD pipelines using GitLab CI and Docker to streamline deployment and testing for multiple Ruby and Python microservices.
Integrated AI-assisted testing solutions to optimize QA workflows, reducing manual effort and enhancing code coverage across complex EXE Software projects.
Designed and executed data annotation and benchmarking processes for experimental AI models, collaborating with cross-functional teams on LLM-related tasks.
Conducted extensive code reviews, identifying anti-patterns, test gaps, and performance bottlenecks, mentoring team members in idiomatic Ruby and OOP practices.
Built containerized solutions using Docker, enabling rapid deployment of experimental ML scripts and Ruby services within cloud environments.
Produced comprehensive documentation for technical debt, defects, and test processes, ensuring project continuity and maintainability across multi-client initiatives.
Orchestrated a complex, large-scale AI integration project combining Ruby and JavaScript systems, enabling model evaluation and deployment while adhering to EXE Software’s stringent quality standards.

Summary

Senior software engineer with 9 years of professional experience specializing in backend and frontend development, cloud systems, and large-scale enterprise applications. Proven expertise in Ruby, Python, JavaScript, and modern DevOps practices, delivering scalable, high-quality solutions across multiple industries. Passionate about AI/ML and LLM projects, combining software engineering excellence with cutting-edge AI model development and evaluation.

Skills

Backend Technologies: Ruby, Spring Boot, Asp.net, Node.js.
Frontend Technologies: React, Blazor, Html, Css.
Tools: Docker, Git, Github Actions, Jenkins, Swagger, Mongodb, Mysql, Microsoft Sql Server, Nunit, Playwright, Selenium, Entity Framework, Dapper.
Programming Languages: Ruby, C#, Java, Javascript, Python, C/c++.

Languages

Romanian

Native

English

Advanced

Education

Oct 2012 - Jun 2016

University of Babeș-Bolyai

Bachelor's degree · Computer Science · Romania

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Experience

Senior Software Engineer

Atos

Software Engineer

EXE Software

Summary

Skills

Languages

Education

University of Babeș-Bolyai

Bachelor's degree · Computer Science · Romania

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