Jacek Maciąg
Verified Expert in Engineering
Ruby and QA Developer
Kraków, Poland
Toptal member since September 20, 2019
Jacek is a Ruby software engineer with a strong background in QA and test automation, which has given him a solid understanding of quality and efficiency in software development. He is passionate about building innovative solutions that solve real-world problems and is always eager to learn new skills and explore emerging technologies. Jacek's curiosity and drive for continuous improvement fuels his ability to adapt to new challenges, making him a dedicated problem-solver and a lifelong learner.
Portfolio
Experience
- Software Development - 5 years
- Quality Assurance (QA) - 5 years
- Ruby - 5 years
- Complex Problem Solving - 4 years
- Object-oriented Programming (OOP) - 4 years
- Java - 4 years
- Git - 3 years
- Cucumber - 2 years
Availability
Preferred Environment
IntelliJ IDEA, Linux, Windows
The most amazing...
...project I've worked on was a market price trend recognition and forecasting tool.
Work Experience
Senior Back-end Engineer
Toptal
- Developed critical client-facing features for Toptal's back end using Ruby on Rails.
- Owned and delivered projects, ensuring timely completion and high quality.
- Researched, designed, and implemented innovative solutions to enhance platform performance.
- Coordinated effectively with other teams and stakeholders to achieve project goals.
Senior QA Automation Engineer
Toptal
- Coordinated quality assurance efforts among multiple teams at Toptal.
- Developed automated testing scripts for client-facing systems.
- Reviewed and tested new features to ensure high-quality deliverables.
- Built innovative solutions to test functionality in a microservice environment.
WordPress QA Specialist
Champion Petfoods
- Tested the company's WordPress and Salesforce-based pages on mobile and desktop platforms.
- Provided valuable insights to the client on key UX issues and recommended solutions.
- Collaborated with the team at Champion Petfoods to ensure quality assurance standards were met.
Quality Assurance
Welltok
- Performed front-end and back-end testing of over 20 applications (functional, integration, and end-to-end).
- Maintained a test environment (deployments, set up, and debugging).
- Developed a test framework and test cases for a Ruby test framework running across various environments.
- Conducted debugging (with Splunk and Sentry) and reported defects (via Rally) of multiple applications across multiple delivery pipelines.
- Worked remotely with a team located across different countries and continents.
Software Developer in Test
Akamai Technologies
- Developed an automated Selenium front-end test framework (Java, TestNG, and Selenium) for a client-facing reporting tool.
- Created automated tests (REST Assured/Retrofit) for an application serving multiple clients.
- Reported and analyzed defects prior to deployment.
- Helped with onboarding and training of new employees.
- Managed and implemented the test framework development.
Quality Control Analyst
Brown Brothers Harriman
- Designed, prepared, and executed manual and automated test scripts.
- Prepared and executed test plans and test strategy documents.
- Developed an automated test framework using Java, Selenium, Serenity + Jenkins/Docker for the bank’s major corporate actions systems.
- Shared knowledge and provided help to non-business team members based on previous experience.
- Provided assistance to UAT and production environment users.
Experience
Schema Check for Services
HelpBot AI Chat Assistant
XTB API Client Ruby Gem
https://github.com/jacekmaciag/xtbEducation
Post-graduate Degree in Systems Design
Akademia Górniczo-Hutnicza im.S.Staszica w Krakowie - Kraków, Poland
Master's Degree in International Relations
Krakowska Akademia im. Andrzeja Frycza Modrzewskiego - Kraków, Poland
Certifications
International English Language Testing System (IELTS) General Training
British Council
ISTQB Certified Tester: Foundation Level
International Software Testing Qualifications Board
Skills
Libraries/APIs
ActiveRecord, Deis, REST APIs, Twilio API, Playwright, Slack API, OpenSSL
Tools
Cucumber, IntelliJ IDEA, Postman, Jira, Rally, Confluence, Git, GitHub, Jenkins, SemaphoreCI, Grafana, DataGrip, PyCharm, Sublime Text 3, Splunk, GitLab, Travis CI, Sentry, Slack, RSpec, ChatGPT
Languages
Ruby, Java, Gherkin, HTML, JavaScript, SQL, CSS, Scala, Python, Bash, PHP, GraphQL
Frameworks
Selenium, JUnit, TestNG, Ruby on Rails (RoR), Ruby on Rails 7, Spring Boot, Cypress, Flask, Ruby on Rails 6, Jest
Paradigms
Automated Testing, Manual Testing, Testing, Test Automation, Functional Testing, E2E Testing, Object-oriented Programming (OOP), Agile, Waterfall Development, Pair Programming, Continuous Delivery (CD), Continuous Integration (CI)
Platforms
Web, Linux, Windows, Google Cloud Platform (GCP), Kubernetes, Docker, WordPress, Amazon Web Services (AWS), Twilio, Android, Mobile
Storage
MySQL, PostgreSQL, MongoDB, Amazon S3 (AWS S3), Datadog
Other
Quality Assurance (QA), QA Testing, Software QA, Manual QA, QA Automation, Website QA, Software Development, Complex Problem Solving, Test Cases, Test Scripting, Documentation, Web App Testing, Regression Testing, APIs, CI/CD Pipelines, API Testing, QA Test Plan Management, Integration Testing, UI Testing, API Integration, Bug Fixes, Cross-browser Testing, Web Development, GitHub Actions, QA Leadership, AI Agents, WordPress Themes, WordPress Design, User Experience (UX), GitHub Workflows, Development, Pact, Back-end, English, Artificial Intelligence (AI), Large Language Models (LLMs), Prompt Engineering, Chatbots, Ruby Gems, WebSockets, HTTPS, Mobile App Testing
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