Jakub is available for hire
Hire JakubJakub Obstarczyk
Verified Expert in Engineering
Quality Assurance Engineer and Developer
Gliwice, Poland
Toptal member since June 25, 2021
Bio
Jakub is a senior QA automation engineer with many years of experience in telecommunications and digital identity. His expertise includes Agile methodologies, test automation, quality assurance, behavior-driven development, and test planning, and he has a keen ability to transition from manual to automated testing. Jakub has designed and implemented QA testing for Mastercard, Capgemini, and several other small and midsized businesses.
Portfolio
Cardano Foundation
API Testing, Automated Testing, Behavior-driven Development (BDD), Appium...
Biconomy
API Testing, Behavior-driven Development (BDD), Automated Testing, Playwright...
Enjin
Mocha, Chai, GitHub, Blockchain, RPC, Quality Assurance (QA), Test Automation...
Experience
- Quality Assurance (QA) - 14 years
- Selenium - 10 years
- Test Automation - 10 years
- C# - 10 years
- Behavior-driven Development (BDD) - 6 years
- API Testing - 6 years
- Playwright - 4 years
- TypeScript - 4 years
Preferred Environment
Selenium, Appium, API Testing, Test Automation, Behavior-driven Development (BDD), Mobile App Testing, Blockchain, Automated Testing, Playwright, TypeScript
The most amazing...
...case I've had with open source is maintaining a Coypu C# framework for web automation that helps thousands of users and companies and has 932,000 downloads.
Work Experience
Senior QA Engineer
2023 - 2025
Cardano Foundation
- Built and managed test suites and test cases on both mobile (iOS and Android) and web applications using TestRail.
- Created and documented comprehensive testing procedures for the team.
- Built automation testing frameworks from scratch for mobile and web projects. In case of mobile application (iOS and Android) regression tests, I've used TypeScript with Appium and WebdriverIO for web application, and TypeScript with Playwright.
- Managed the final quality assurance and sign-off for mobile application releases to the Apple App Store and Google Play Store.
- Escalated concerns about project and process quality, referring discovered issues to the engineering manager for resolution.
- Facilitated knowledge sharing and best practices among team members.
- Participated in the training, onboarding, and hiring of new team members.
- Reviewed product user stories from a QA perspective to ensure testability and clarity.
Technologies: API Testing, Automated Testing, Behavior-driven Development (BDD), Appium, WebdriverIO, TypeScript, Playwright, Postman, TestRail, Jira, GitHub, GitHub Actions, Mobile App Testing, Web App Testing, Manual QA, Automation
QA Lead
2022 - 2023
Biconomy
- Established QA processes within the company and led and mentored QA team members.
- Liaised between the QA team and other departments, providing project updates and consultation.
- Developed an automation framework for regression functional tests for our front-end app using TypeScript with Playwright.
- Created an automation framework for regression tests of the microservice REST API back-end app using TypeScript with Playwright.
- Introduced a standardized approach and tools for writing automated tests across all teams.
- Monitored resolution of bugs, test fixes, and helped developers tackle ongoing problems by providing a QA perspective.
Technologies: API Testing, Behavior-driven Development (BDD), Automated Testing, Playwright, Python, TypeScript, REST APIs, Docker, Web App Testing, Jira, Zephyr, GitHub Actions, GitHub, Manual QA, Web Applications, Automation
Senior QA Engineer
2021 - 2022
Enjin
- Introduced QA processes and fit them into the overall SDLC process within the team to be aligned with good Agile methodology practices.
- Learned a new tech stack of JavaScript ES6 used with Mocha and Chai.js to automate our regression tests.
- Raised the automation coverage of regression tests for our back end of the parachain blockchain.
- Performed code reviews of PRs of other team members involved in the project.
- Introduced test suites and cases for parachain under test through the x-ray add-on for Jira.
- Performed manual and exploratory testing of API endpoints through Polkadot.js web app tools.
- Onboarded new QA members about the process within the team.
Technologies: Mocha, Chai, GitHub, Blockchain, RPC, Quality Assurance (QA), Test Automation, JavaScript, API Testing, Exploratory Testing, Manual Testing, Visual Studio Code (VS Code), WebStorm, Postman, Automated Testing, Playwright, QA Automation, Manual QA, Web Applications, Automation
Senior Software Development Engineer in Test
2019 - 2021
Mastercard
- Created automation frameworks in Java for a microservices platform, using JUnit and REST Assured with JBehave and Cucumber for the BDD layer through IntelliJ IDEA (v2019–2020) to automate test cases related to API endpoints through HTTP methods.
- Developed an automation framework in C# for a microservices platform, using NUnit with RestSharp along with SpecFlow for the BDD layer through Visual Studio 2019 to automate test cases related to API endpoints through HTTP methods.
- Performed manual and exploratory testing of API endpoints through Postman and Insomnia tools.
- Conducted manual and exploratory testing of mobile apps using real devices, iOS simulators, Android emulators, and devices from the BrowserStack cloud solution.
- Introduced testers into the early review of the stories and features to improve the overall SDLC process by catching potential issues earlier.
- Created a thorough Git repository and ran Jenkins jobs for API test execution and the overall CI/CD process within Mastercard.
- Developed a proof of concept framework in Java, using Cucumber, JUnit, and Selenium to automate a web page application. The framework was later integrated into the overall test infrastructure.
- Used Rally project management software to work with stories and features and log any bugs and issues throughout the SDLC process.
- Deployed releases of back-end platform applications into production.
- Mentored and onboarded new QA members within the team.
Technologies: API Testing, Behavior-driven Development (BDD), Git, Java, JUnit, JBehave, Cucumber, Jenkins, Rally, BrowserStack, Postman, C#, SpecFlow, IntelliJ IDEA, Visual Studio, RestSharp, REST Assured, NUnit, Quality Assurance (QA), SDET, Automated Testing, QA Automation, Mobile Apps, REST, REST APIs, UI Testing, Playwright, Manual QA, Automation
Senior QA Automation Engineer
2018 - 2019
Ding
- Coordinated knowledge sharing among senior members of the team.
- Introduced a standardized approach and tools, such as a Coypu C# framework, SpecFlow for BDD, and Selenium and Appium for writing automated test cases across all back-end, front-end, and mobile teams.
- Supervised and trained junior members and interns in the QA team.
- Introduced a Puppet configuration management tool to replace PowerShell Desired State Configuration to keep up-to-date virtual machines on QA servers.
- Wrote automated, functional end-to-end tests for web and mobile apps in C# through Visual Studio 2017 and 2019, using Page Object Model (POM), Selenium WebDriver, Appium, SpecFlow, and NUnit, on top of a Coypu C# framework.
- Created an automation framework in C# for a microservices platform, using NUnit with RestSharp along with SpecFlow for the BDD layer through Visual Studio 2019 to automate test cases related to API endpoints through HTTP methods.
- Maintained and improved JMeter performance tests for the company's main product, ding.com, a mobile top-up app.
- Performed exploratory testing of REST API endpoints through Postman.
- Released web, mobile, and back-end platform applications to production.
- Set up continuous integration in projects using Git, Jenkins, and Octopus Deploy and maintained Jenkins QA-related jobs through Groovy files in a Git repository.
Technologies: API Testing, Behavior-driven Development (BDD), Appium, C#, Apache JMeter, SpecFlow, Web App Testing, Test Automation, NUnit, Jenkins, .NET, Selenium, Postman, Quality Assurance (QA), QA Automation, Selenium Grid, REST, REST APIs, UI Testing, Datadog, Playwright, Manual QA, Web Applications, Automation
QA Automation Engineer
2015 - 2018
Ding
- Wrote automated, functional, end-to-end tests for web and mobile apps in C# through Visual Studio 2015 and 2017, using POM, Selenium WebDriver, Appium, SpecFlow, and NUnit on top of a Coypu C# framework, spending 70% of my time on this.
- Introduced parallel test runs to reduce test execution time by refactoring existing C#-based source code to allow test runs in a Selenium Grid nodes setup.
- Wrote automated tests in C# for a microservices platform, using NUnit with RestSharp along with SpecFlow for the BDD layer through Visual Studio 2019, to automate test cases related to API endpoints through HTTP methods.
- Recruited new team members for QA-related positions.
- Introduced JMeter for performance testing of ding.com, the company's main product.
- Used Docker containers to run T-SQL databases for the back-end platform application.
- Migrated from a Scrumban approach to the Kanban Agile methodology.
- Released web, mobile, and back-end platform applications to production.
- Set up continuous integration for projects using TFS and Git, Jenkins, and Octopus Deploy.
- Integrated nightly Jenkins jobs with BrowserStack.
Technologies: C#, Behavior-driven Development (BDD), SpecFlow, NUnit, Windows PowerShell, TFS, Git, Jira, Web App Testing, Manual Testing, Mobile App Testing, Test Automation, SQL, Docker, API Testing, Quality Assurance (QA), Mobile Apps, Automated Testing, REST APIs, UI Testing, QA Automation, Manual QA, Automation
QA Engineer
2013 - 2015
Ding
- Performed manual testing and verified bug fixes in the ding.com web application that has around 250,000 transactions per day, in supporting apps in the back end, and in the Ding and Digicel mobile (Android and iOS) applications.
- Wrote automated functional tests in C# for web applications in Visual Studio 2013 with Selenium WebDriver and Appium.
- Set up continuous integration in projects, using TFS, Jenkins, and Octopus Deploy. Tracked bugs and other card types in Jira.
- Used SQL Server Management Studio 2012 to test databases.
- Performed QA reviews on product user stories as candidates for new features.
- Added new test cases to the Zephyr test case management tool in Jira.
Technologies: C#, Jira, Windows PowerShell, Jenkins, Octopus Deploy, SQL Server Management Studio (SSMS), Quality Assurance (QA), UI Testing, Mobile Apps, QA Automation, Manual QA, Automation
Test Analyst
2011 - 2013
Capgemini Poland
- Wrote automated functional tests in C# for Silverlight and ASP.NET applications in Telerik Test Studio Express (a plugin for Visual Studio 2012) along with Selenium WebDriver.
- Set up continuous integration in projects, using TFS, TeamCity, and TortoiseSVN.
- Tested databases using SQL Server Management Studio 2008.
- Performed manual testing and verified the bug fixes in Microsoft Silverlight and ASP.NET applications.
- Created test suites and test cases for applications in Microsoft Test Manager.
- Wrote user guides for applications for end users in PDF format.
- Gained experience in applying operational acceptance testing processes.
Technologies: C#, TortoiseSVN, TFS, TeamCity, NUnit, Microsoft Test Manager, Telerik Test Studio, SQL Server Management Studio (SSMS), Selenium, Quality Assurance (QA), QA Automation, Manual QA, Automation
QA Tester
2010 - 2011
Lunar Logic
- Performed manual testing and verified bug fixes in Ruby and mobile applications.
- Created test suites and test cases for applications in TestRail.
- Set up automated functional testing of Ruby applications using Selenium IDE.
- Created a JMeter load testing job for a web page requested by a client.
- Gained experience in applying Scrumban Agile methodology while working on company projects.
Technologies: Selenium IDE, Apache JMeter, Manual Testing, Web App Testing, TestRail, Quality Assurance (QA), QA Automation, Manual QA, Automation
QA Engineer
2008 - 2010
Connect2Media
- Performed manual testing and verified bug fixes in the gameplay of Java mobile games on cell phones.
- Performed manual testing of the online mode in Java mobile games on cell phones.
- Analyzed the mechanisms influencing user gameplay and pathways of simple browser web games based on franchises like Guitar Hero III and Iron Man 2.
Technologies: Mobile App Testing, Manual Testing, Quality Assurance (QA), Manual QA, Automation
Software Tester
2007 - 2008
Sygnity
- Created test scenarios for Java Desktop applications on Windows machines.
- Performed manual testing and verified the bug fixes in Java Desktop applications on Windows machines.
- Gained experience in applying the Waterfall methodology to the SDLC within the company.
Technologies: Manual Testing, Quality Assurance (QA), Manual QA
Experience
Web Automation for Ding.com
Automated testing for web and mobile applications and APIs for various products, including the main product, ding.com. The ding.com web automation project was created using C#, and we were able to run it on different environments, from local, to test, to staging, to production, across various browsers and operating systems through integration with Selenium Grid and later through BrowserStack. This provided proper end-to-end coverage of functional testing for the user flows. I was involved in developing and deploying this automated testing for 6.5 years.
Coypu Framework | Open-source Project
https://github.com/featurist/coypuCoypu supports browser automation in .NET to help make tests readable, robust, fast to write, and less tightly coupled to the UI. It was developed in C# and is based on an idea from the Capybara test framework created for Ruby on Rails developers. I am the main contributor to the project on GitHub, which was downloaded from NuGet more than 940,000 times.
Skills
Libraries/APIs
Playwright, Chai, Selenium Grid, REST APIs
Tools
Cucumber, Postman, Visual Studio, Git, Jira, RestSharp, REST Assured, Apache JMeter, Jenkins, Rally, TFS, TortoiseSVN, TeamCity, BrowserStack, Microsoft Test Manager, Telerik Test Studio, TestRail, IntelliJ IDEA, Mocha, GitHub, WebStorm, Zephyr, WebdriverIO
Languages
C#, Java, SQL, ECMAScript (ES6), JavaScript, Python, TypeScript
Frameworks
Selenium, SpecFlow, Appium, JBehave, .NET, Windows PowerShell, NUnit, JUnit
Paradigms
Test Automation, Behavior-driven Development (BDD), Manual Testing, Automation, Automated Testing, REST
Platforms
Windows, MacOS, Docker, Blockchain, Visual Studio Code (VS Code)
Storage
Datadog, SQL Server Management Studio (SSMS)
Other
API Testing, Web App Testing, Quality Assurance (QA), QA Automation, Manual QA, Web Applications, Mobile App Testing, Test Automation Frameworks, Octopus Deploy, Selenium IDE, RPC, Exploratory Testing, SDET, Mobile Apps, UI Testing, GitHub Actions
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