Marek Pawlak - Senior Software Engineer

Warsaw, Poland

Experience

Sep 2018 - Present

7 years 5 months

Warsaw, Poland

Senior Software Engineer

SoftwareMill

Designed and implemented Ruby-based backend services using object-oriented and idiomatic Ruby practices to support scalable business platforms, resulting in stable and maintainable codebases
Reviewed and refactored legacy Ruby applications using metaprogramming techniques to reduce duplication and improve extensibility across multiple domains
Led code reviews focused on identifying code smells, anti-patterns, and test gaps in Ruby and mixed-language repositories, improving overall code quality standards
Developed automated test suites with RSpec and Minitest integrated into CI pipelines, ensuring consistent verification of business logic before releases
Built CI/CD workflows using GitHub Actions and GitLab CI to automate testing, static analysis, and deployment validation
Implemented Docker-based development and testing environments to ensure reproducibility across engineering teams
Collaborated with cross-functional teams to define coding guidelines and quality benchmarks for backend Ruby services
Actively contributed production code while mentoring senior and mid-level engineers on Ruby best practices and maintainable design
analyzed production defects using profiling and debugging tools to identify root causes and document technical debt
Produced high-quality technical documentation describing system behavior, test coverage, and known limitations
Worked with Python and TypeScript components alongside Ruby services to support multi-language system integration
Participated in experimental projects involving AI-assisted development, including prompt evaluation and automated code generation validation
Evaluated model-generated Ruby code for correctness, performance, and stylistic alignment with idiomatic standards
Adapted internal engineering guidelines to new domains and evolving technical requirements
Supported asynchronous collaboration workflows through clear written communication and structured documentation

Jan 2015 - Aug 2018

3 years 8 months

Hanoi, Viet Nam

Full-Stack Engineer

CMC Global Company Limited

Developed Ruby-based backend features for business applications using clean object-oriented design and modular architecture
Implemented RESTful APIs and background processing logic while maintaining high test coverage through automated tests
Performed systematic code reviews to identify defects, refactoring opportunities, and missing test scenarios
Integrated Ruby applications into CI environments using Jenkins and GitLab CI for automated testing and validation
Built and maintained Docker images to standardize development and deployment environments
Collaborated with QA teams to document defects, reproduce issues, and verify fixes in Ruby codebases
Improved application reliability by profiling Ruby services and optimizing performance bottlenecks
Wrote clear technical documentation for backend components, test strategies, and known technical constraints
Contributed to frontend features using JavaScript and TypeScript to support full-stack delivery
Maintained version control workflows using Git, including branching, rebasing, and conflict resolution
Assisted in onboarding engineers by explaining Ruby conventions, testing practices, and debugging techniques
Participated in internal hackathon-style initiatives focused on rapid prototyping and problem-solving
Supported multi-project environments requiring quick context switching and guideline adaptation
Ensured Linux-based deployment scripts and automation tasks were reliable and well-documented
Collaborated closely with technical leads to align implementation details with architectural direction

Sep 2011 - Dec 2014

3 years 4 months

Ho Chi Minh City, Viet Nam

Frontend Web Developer

TMA Solutions

Developed and maintained web applications while collaborating closely with backend Ruby and Java services
Reviewed frontend and integration code to ensure consistency with backend APIs and data contracts
Assisted backend teams by debugging Ruby-related integration issues from the client perspective
Used Git-based workflows to manage feature development and bug fixes across shared repositories
Documented defects and implementation details to support long-term maintainability
Worked in Linux environments using CLI tools for development, testing, and troubleshooting
Collaborated with designers and backend engineers to translate requirements into working features
Contributed to improving development guidelines and internal documentation practices

Summary

I’m a Senior Software Engineer with over 13 years of professional experience building, reviewing, and maintaining production-grade software systems across backend, frontend, and full-stack domains. I have a strong background in Ruby development, object-oriented design, code quality analysis, and test-driven development, combined with hands-on experience in CI/CD pipelines, containerized environments, and multi-language ecosystems. I’m highly comfortable working with complex guidelines, evaluating and generating code, reviewing large codebases, and collaborating on experimental and AI-driven initiatives that require precision, adaptability, and deep technical judgment.

Skills

Languages: Ruby, Python, Javascript, Typescript, Sql, Bash
Ruby Expertise: Object-oriented Programming, Metaprogramming, Idiomatic Ruby, Refactoring, Code Smells, Anti-patterns
Testing & Quality: Rspec, Minitest, Test Coverage Analysis, Test Automation, Ci-integrated Testing
Ci/cd & Devops: Github Actions, Gitlab Ci, Jenkins, Docker, Linux Cli, Automated Deployments
Ai & Llm Workflows: Code Generation, Prompt Evaluation, Model-assisted Coding, Benchmarking, Data Annotation
Architecture: Modular Design, Service-oriented Systems, Event-driven Patterns, Maintainability
Tooling: Git, Profilers, Debuggers, Linters, Static Analysis Tools
Documentation: Technical Documentation, Defect Reports, Test Plans, Technical Debt Tracking

Languages

Vietnamese

Native

English

Advanced

Polish

Advanced

Education

Sep 2007 - Jun 2011

Vietnam National University, Hanoi

Bachelor's degree, Computer Science · Computer Science · Hanoi, Viet Nam

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Experience

Senior Software Engineer

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Summary

Skills

Languages

Education

Vietnam National University, Hanoi

Bachelor's degree, Computer Science · Computer Science · Hanoi, Viet Nam

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