Christina Lin, Developer in Vancouver, BC, Canada
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Christina Lin

Bio

Christina is a senior QA engineer with 10+ years of experience working at startups, large enterprises, and government organizations. She builds automation frameworks and integrates AI-driven testing solutions with Selenium, Appium, Cypress, RestAssured API, and GPT -3 Driver. She also brings strong manual testing expertise across web and mobile. She is a strong collaborator with a track record of improving release confidence and delivering high-quality results on remote teams.

Portfolio

Yahoo!
Xcode, Swift, Agile, iOS, Android, GitHub, XCUITest, Charles Proxy...
Duolingo
Git, Xcode, Swift, Java, Python, Selenium WebDriver, Appium, QA Automation...
nCrypt
Jira, TestRail, Git, Apache Maven, TestNG, Java, Appium, Selenium WebDriver...

Experience

  • Quality Assurance (QA) - 14 years
  • Web App Testing - 14 years
  • QA Automation - 11 years
  • Selenium WebDriver - 10 years
  • Mobile App Testing - 8 years
  • Appium - 7 years
  • API Testing - 3 years
  • AI Testing - 2 years

Preferred Environment

Windows, MacOS, .NET, Python, Java, Jira

The most amazing...

...project I've done was developing a test automation framework from the ground up. It helped reduce manual testing time from four days to one day!

Work Experience

QA Engineer

2025 - 2025
Yahoo!
  • Analyzed business requirements, design documents, and created test cases for project milestones, integrating AI to help generate test cases.
  • Performed manual testing on iOS and Android mobile apps for Yahoo Sports and Fantasy Sports. Participated in team bug bashes. Reported bugs and communicated with developers to reach a resolution.
  • Monitored and fixed test automation build flakiness to ensure stability of test runs.
Technologies: Xcode, Swift, Agile, iOS, Android, GitHub, XCUITest, Charles Proxy, Fantasy Sports, Sports, Jira, AI Testing, Agile QA, CI/CD Pipelines, Test Scripting, Test Scenarios, Agile Sprints, Test Documentation, Automation, QA Process, Validation, React

Senior Test Automation Engineer

2018 - 2024
Duolingo
  • Implemented cross-platform automation frameworks for web, Android, and iOS applications using Selenium WebDriver, Cypress, and Appium.
  • Scripted AI-generated automation tests using MobileBoost GPT driver.
  • Conducted functional, regression, and exploratory testing across multiple browsers and devices to ensure a seamless end-user experience.
  • Monitored CI/CD automation builds, triaged test failures, investigated root causes of failures, and reported results to stakeholders for timely defect resolution.
Technologies: Git, Xcode, Swift, Java, Python, Selenium WebDriver, Appium, QA Automation, SDET, Quality Assurance (QA), Software Development, Automated Testing, Mobile Apps, XCUITest, Agile Sprints, Test Scripting, Android Testing, Selenium, Jira, iOS, Android, Jenkins, Python 3, GitHub, QA Testing, Regression Testing, Integration Testing, System Testing, Exploratory Testing, Test Case Execution, Test Case Creation, Software Testing Lifecycle (STLC), Test Analysis, Website QA, Website Testing, Web App Testing, Web-based Testing, Black Box Testing, Test Automation Frameworks, Automated UI Testing, Selenium PageFactory, UI Automation, Software QA, Manual QA, Software Development Lifecycle (SDLC), Test Cases, Agile Software Testing, Selenium Page Object, White Box Testing, Mobile App Testing, Software Testing, Functional Testing, E2E Testing, Testing, Test Automation, Selenium API, Unit Testing, Eclipse IDE, Confluence, Mobile Device QA Automation, JSON, WebDriver, UI Testing, Smoke Testing, Test Scenarios, Manual Testing, XPath, CI/CD Pipelines, Android Auto, Cypress, Artificial Intelligence (AI), Manual Software Testing, Bug Discovery & Tracking, Documentation, Quality Control (QC), AI Testing, Test Documentation, Automation, QA Process, Node.js, Validation, React

QA Automation Engineer

2017 - 2018
nCrypt
  • Designed and implemented a Selenium-based automation framework in Java from scratch, ensuring test reusability and modularity.
  • Automated high-value regression test cases for a crypto exchange platform, improving release validation speed by 70%.
  • Delivered automation test coverage metrics and framework demos to the development team, strengthening visibility of QA efforts.
  • Performed manual testing on nCrypt's bitcoin and bitcoin cash exchange web application.
Technologies: Jira, TestRail, Git, Apache Maven, TestNG, Java, Appium, Selenium WebDriver, QA Automation, SDET, Quality Assurance (QA), Software Development, Automated Testing, Mobile Apps, Test Scripting, Selenium, iOS, API Testing, Databases, Cryptocurrency, QA Testing, Regression Testing, Integration Testing, System Testing, Exploratory Testing, Test Case Execution, Test Case Creation, Software Testing Lifecycle (STLC), Test Analysis, Website QA, Website Testing, Web App Testing, Web-based Testing, Black Box Testing, Test Automation Frameworks, Automated UI Testing, Test Management, Selenium PageFactory, QA Leadership, UI Automation, Software QA, Manual QA, Software Development Lifecycle (SDLC), Test Cases, Selenium Page Object, Web Service Testing, Software Testing, Functional Testing, E2E Testing, Testing, Test Automation, Selenium API, Eclipse IDE, REST Assured, Mobile Device QA Automation, Zephyr, APIs, WebDriver, UI Testing, Smoke Testing, Test Planning, Test Scenarios, Manual Testing, XPath, Cross-browser Testing, Manual Software Testing, Bug Discovery & Tracking, Documentation, Startups, Quality Control (QC), Agile QA, Test Documentation, Automation, QA Process, Validation, React

Senior QA Automation Engineer

2016 - 2017
BCAA
  • Built end-to-end regression automation suites with Selenium WebDriver and Java for a customer relationship management and insurance sales application, reducing manual testing overhead.
  • Developed RESTful API automation using REST Assured to validate back-end services for the PIPA project.
  • Performed manual, database, and iPhone testing to ensure quality consistency across customer-facing systems.
  • Worked under Scrum methodology to increase the visibility of QA efforts in Scrum ceremonies.
Technologies: pgAdmin, Postman, Swagger, TestLink, Bamboo, Subversion (SVN), Git, SQL, TestNG, Java, Selenium WebDriver, QA Automation, SDET, Quality Assurance (QA), Software Development, Automated Testing, Mobile Apps, Agile Sprints, Test Scripting, Selenium, API Testing, Databases, QA Testing, Regression Testing, Integration Testing, System Testing, Exploratory Testing, Test Case Execution, Test Case Creation, Software Testing Lifecycle (STLC), Test Analysis, Website QA, Website Testing, Web App Testing, Web-based Testing, Black Box Testing, Test Automation Frameworks, Automated UI Testing, Selenium PageFactory, UI Automation, Software QA, Manual QA, Software Development Lifecycle (SDLC), Test Cases, Agile Software Testing, Selenium Page Object, Web Service Testing, Software Testing, Functional Testing, E2E Testing, Testing, Test Automation, Selenium API, Eclipse IDE, REST Assured, JSON, TortoiseGit, TortoiseSVN, APIs, WebDriver, UI Testing, Smoke Testing, Mobile App Testing, Bitbucket, Test Scenarios, Manual Testing, XPath, CI/CD Pipelines, BrowserStack, Cross-browser Testing, Manual Software Testing, Bug Discovery & Tracking, Documentation, Quality Control (QC), Agile QA, Cucumber, Test Documentation, Automation, QA Process, Node.js, Validation, React

Test Lead

2015 - 2016
Treasury Board of Canada Secretariat
  • Created a test automation framework from scratch using Selenium WebDriver, JavaScript/Protractor, and Python for an intranet migration initiative for the Ontario government on a WordPress platform.
  • Authored the Test Strategy document to outline testing approaches and align QA methodologies with business and technical requirements.
  • Led testing efforts and provided QA training to junior testers.
  • Created and executed web accessibility (WCAG 2.0) test cases.
Technologies: Wave, TestLink, Git, Unit Testing, Python, Selenium WebDriver, QA Automation, SDET, Quality Assurance (QA), Software Development, Automated Testing, Agile Sprints, Leadership, Test Scripting, Selenium, Python 3, Protractor, Jasmine, WordPress, QA Testing, Regression Testing, Integration Testing, System Testing, Exploratory Testing, Test Case Execution, Test Case Creation, Software Testing Lifecycle (STLC), Test Analysis, Website QA, Website Testing, Web App Testing, Web-based Testing, Black Box Testing, Test Automation Frameworks, Automated UI Testing, Test Management, Selenium PageFactory, QA Leadership, UI Automation, Software QA, Manual QA, Software Development Lifecycle (SDLC), Test Cases, Agile Software Testing, Selenium Page Object, Software Testing, Functional Testing, E2E Testing, Testing, Test Automation, Selenium API, Eclipse IDE, IE Developer Toolbar, WebDriver, UI Testing, Smoke Testing, Phabricator, Test Scenarios, Manual Testing, XPath, Web Accessibility, Accessibility Testing, Content Management Systems (CMS), Data Migration Testing, Manual Software Testing, User Testing, Bug Discovery & Tracking, Documentation, Quality Control (QC), Testing Strategy, Agile QA, Test Documentation, Automation, QA Process, Node.js, Validation, React

Software Test Developer

2015 - 2015
Ecobee
  • Developed automated tests for a web application that allowed users to configure Ecobee's WiFi-enabled thermostat.
  • Maintained and troubleshot the automation environments.
  • Monitored automation test results daily and fixed bugs as needed.
  • Mentored junior automation testers on coding standards.
Technologies: TestLink, Jenkins, Subversion (SVN), PyUnit, Python, Selenium WebDriver, QA Automation, SDET, Quality Assurance (QA), Software Development, Automated Testing, Test Scripting, Selenium, Jira, Python 3, QA Testing, Regression Testing, Integration Testing, System Testing, Exploratory Testing, Test Case Execution, Test Case Creation, Software Testing Lifecycle (STLC), Test Analysis, Website QA, Website Testing, Web App Testing, Web-based Testing, Black Box Testing, Test Automation Frameworks, Automated UI Testing, Selenium PageFactory, UI Automation, Software QA, Manual QA, Software Development Lifecycle (SDLC), Test Cases, Selenium Page Object, Software Testing, Functional Testing, E2E Testing, Testing, Test Automation, Selenium API, Eclipse IDE, Confluence, JSON, WebDriver, UI Testing, CSS, Smoke Testing, Test Scenarios, Manual Testing, CI/CD Pipelines, Cross-browser Testing, Manual Software Testing, Bug Discovery & Tracking, Documentation, Startups, Test Documentation, Automation, QA Process, Node.js, Validation, React

Test Automation Engineer

2014 - 2014
Carebook Health Technologies
  • Developed C#-based Selenium WebDriver UI automation scripts for a SaaS preventative health management system.
  • Mentored offshore QA testers on creating effective and maintainable test suites to provide maximum test coverage for different testing phases.
  • Wrote performance test scripts using Visual Studio Web Performance Test.
  • Performed functional, regression, web, and mobile testing on Carebook's SaaS platform.
  • Analyzed functional specs, requirements, and workflow designs.
Technologies: TFS, Microsoft Team Foundation Server, Microsoft Test Manager, Visual Studio, Microsoft Visual Studio, NUnit, C#, Selenium WebDriver, QA Automation, SDET, Quality Assurance (QA), Software Development, Automated Testing, .NET, Agile Sprints, Leadership, Test Scripting, Selenium, C#.NET, QA Testing, Regression Testing, Integration Testing, System Testing, Exploratory Testing, Test Case Execution, Test Case Creation, Software Testing Lifecycle (STLC), Test Analysis, Website QA, Website Testing, Web App Testing, Web-based Testing, Black Box Testing, Test Automation Frameworks, Automated UI Testing, Test Management, Selenium PageFactory, QA Leadership, UI Automation, Software QA, Manual QA, Software Development Lifecycle (SDLC), Test Cases, Agile Software Testing, Selenium Page Object, Software Testing, Functional Testing, E2E Testing, Testing, Test Automation, Selenium API, WebDriver, UI Testing, CSS, Smoke Testing, Test Planning, Mobile App Testing, Team Foundation Server 2013, Test Scenarios, Manual Testing, XPath, Data Migration Testing, Manual Software Testing, User Testing, Bug Discovery & Tracking, Documentation, Startups, Quality Control (QC), Agile QA, Test Documentation, Automation, QA Process, Validation

Senior QA Analyst

2013 - 2014
Western Union
  • Analyzed business requirements, UI workflow, and database design to create and execute test cases on a transaction monitoring and alert management system for detecting money laundering patterns for regulatory compliance (PEP, Worldcheck, Dodd-Frank).
  • Designed the test plan and test case templates and created the entire regression testing suite.
  • Performed black box and white box functional, regression, integration, database, and UI testing.
  • Configured HP Quality Center as a test management system for full traceability across requirements, tests, and defects.
  • Provided test coverage and defect summary reports for project releases.
Technologies: VersionOne, Trello, HP Quality Center (QC), SQL Server Management Studio (SSMS), QA Automation, SDET, Quality Assurance (QA), Software Development, Automated Testing, Test Scripting, API Testing, Databases, QA Testing, Regression Testing, Integration Testing, System Testing, Exploratory Testing, Test Case Execution, Test Case Creation, Software Testing Lifecycle (STLC), Test Analysis, Website QA, Website Testing, Web App Testing, Web-based Testing, Black Box Testing, Software QA, Manual QA, Software Development Lifecycle (SDLC), Test Cases, Software Testing, Functional Testing, E2E Testing, Testing, Test Automation, Salesforce, UI Testing, Smoke Testing, Test Scenarios, Manual Testing, Content Management Systems (CMS), Manual Software Testing, Bug Discovery & Tracking, Documentation, Quality Control (QC), Test Documentation, QA Process, Node.js, Validation

Test Lead

2011 - 2013
Provincial Health Services Authority
  • Performed functional, integration, regression, security, and automated testing for a renal patient information management system used across BC renal clinics and hospitals.
  • Managed a team of four testers, defined the scope of testing, planned and led project testing efforts, and established and standardized QA processes. Developed the test strategy. Participated in UAT planning and triaged user feedback.
  • Evaluated, recommended, and coordinated the purchase and training of test management, requirements management, test automation, and bug-tracking tools. Set up and maintained all QA tools.
  • Designed test plan, test case, and defect templates. Developed test estimations.
  • Determined QA resource needs and participated in the QA hiring process.
Technologies: Jira, HP Quality Center (QC), QTP, Java, Selenium WebDriver, QA Automation, SDET, Quality Assurance (QA), Software Development, Automated Testing, Agile Sprints, Leadership, Test Scripting, Selenium, QA Testing, Regression Testing, Integration Testing, System Testing, Exploratory Testing, Test Case Execution, Test Case Creation, Software Testing Lifecycle (STLC), Test Analysis, Website QA, Website Testing, Web App Testing, Web-based Testing, Black Box Testing, Test Automation Frameworks, Automated UI Testing, Test Management, Selenium PageFactory, QA Leadership, UI Automation, Software QA, Manual QA, Software Development Lifecycle (SDLC), Test Cases, Agile Software Testing, Selenium Page Object, Software Testing, Functional Testing, E2E Testing, Testing, Test Automation, Selenium API, Eclipse IDE, Confluence, User Acceptance Testing (UAT), TortoiseSVN, TortoiseGit, HP QuickTest Professional (QTP), WebDriver, UI Testing, Smoke Testing, Test Planning, Test Scenarios, Manual Testing, XPath, Data Migration Testing, Manual Software Testing, User Testing, Bug Discovery & Tracking, Documentation, Quality Control (QC), Testing Strategy, Agile QA, Test Documentation, Automation, QA Process, Node.js, Validation, React

Software Tester

2010 - 2011
The Active Network
  • Analyzed functional specifications, created and executed test cases for Point of Sale (POS), payment transaction processing, and event registration systems.
  • Tested the SQL encryption for payment data transmission from client to server using a Microsoft Network Monitor.
  • Performed website accessibility testing for ADA compliance.
  • Presented demos of new software features to stakeholders and customers.
  • Collaborated with offshore developers and testers.
  • Implemented hardware testing on cash drawers, receipt printers, validation printers, scanners, and webcams.
Technologies: IIS, JAWS, Accessibility, Wave, IE Developer Toolbar, Web Accessibility, Oracle Database, Jira, Microsoft SQL Server, Quality Assurance (QA), Agile Sprints, Test Scripting, Databases, QA Testing, Regression Testing, Integration Testing, System Testing, Exploratory Testing, Test Case Execution, Test Case Creation, Software Testing Lifecycle (STLC), Test Analysis, Website QA, Website Testing, Web App Testing, Web-based Testing, Black Box Testing, Software QA, Manual QA, Software Development Lifecycle (SDLC), Test Cases, Agile Software Testing, White Box Testing, Software Testing, Functional Testing, E2E Testing, Testing, Test Automation, UI Testing, XML, Smoke Testing, Test Scenarios, Manual Testing, Accessibility Testing, Cross-browser Testing, Manual Software Testing, Bug Discovery & Tracking, Documentation, Quality Control (QC), Agile QA, Test Documentation, QA Process, Validation

Software Developer

2010 - 2010
SAP Business Objects
  • Added and modified installation features to the Business Objects Enterprise application on both Windows and Unix platforms.
  • Developed installation features to support different language localizations.
  • Developed installation features to support different types of databases.
Technologies: Visual Studio, C++, QA Automation, SDET, Quality Assurance (QA), Automated Testing, Test Scripting, Software Development Lifecycle (SDLC), Perforce, Documentation, QA Process

Software Developer

2008 - 2008
Currenex
  • Converted all of the embedded test code into JUnit test cases.
  • Developed an administrator setup application using Java, JavaScript, Ajax, and SQL that allowed the superuser to add, edit, and delete administrators.
  • Gathered the requirements, then developed the user interface design, and implemented both front-end and back-end code.
  • Wrote SQL database queries and conducted unit and integration testing.
  • Managed the integration into the main application.
  • Added user group deletion, user filtering, and user search features to the existing application.
Technologies: SQL, JavaScript, Java, QA Automation, SDET, Quality Assurance (QA), Software Development, Automated Testing, Test Scripting, Exploratory Testing, Software Development Lifecycle (SDLC), Unit Testing, Eclipse IDE, JUnit, Documentation, Quality Control (QC), QA Process

Software Engineer

2007 - 2007
MacDonald, Dettwiler, and Associates (MDA)
  • Implemented classes in C++ to build a “bridge” to transport navigation aid data from the database to the front-end layers of the application.
  • Developed backend code to deliver data to the UI layer.
  • Developed backend code to deliver data to the UI layer.
Technologies: C++, QA Automation, SDET, Quality Assurance (QA), Software Development, Automated Testing, Test Scripting, Software Development Lifecycle (SDLC), XML, Documentation, QA Process

Experience

Building the Entire Test Automation Framework at nCrypt

As the first QA automation engineer hired at the company, I had the opportunity to build the test automation project from the ground up. I used Selenium WebDriver with Java, TestNG, and Maven. I incorporated Log4J for logging test steps and error stack trace to a log file, and I added ExtentReports for generating a user-friendly HTML report to display the test results.

I automated all the critical and commonly-used workflows in the front-end web application, and the automation suite was run during regression testing period to reduce manual testing time and efforts. The QA team especially appreciated the fact that the automated tests replaced some of the most tedious and time-consuming manual test cases that involved number calculations and checking for the correct cash, bitcoin, and bitcoin cash balances in the customers' wallets within the application.

Building an API Test Suite to Test RESTful Web Services

At BCAA, I was involved in a data tokenization project that required web services API testing. Since no one on my team had done API testing before, I took the initiative to build the test suite from scratch. As we were a Java shop, I used the REST Assured Java framework to test the REST API endpoints.

After creating the testing framework and the initial set of test cases, I mentored another tester on REST services and the programming syntax for writing API tests. The project was a success, and the entire test suite was run on a daily basis in Bamboo, our continuous integration tool.

Leading the QA Activities for a Brand-new Government Agile Project

I was hired as a test lead and QA automation engineer for a brand-new Agile project at a government agency. The project's purpose was to redesign and rebuild the intranet so it could function as a collaboration and knowledge-sharing platform for employees.

After some discussions with the development team, we decided to build the test automation project in Python because it was the language that the majority of the developers was comfortable with. I built the test automation framework from scratch using Selenium WebDriver and automated the tests for all the new features that the developers produced in each sprint.

In addition to building the entire test automation framework, I also mentored junior testers, set up, and configured test management and defect tracking systems, performed accessibility testing for the hearing-impaired, and created the test strategy document for submission to the senior management.

The Agile project we worked on served as a pioneering example for other departments within the organization, and we frequently had colleagues visit our office to learn how we used the Agile methodology to deliver our project incrementally and successfully.

Serving as a Mentor in UBC's Computer Science Mentorship Program

Since 2006, I have been volunteering as a mentor in the computer science mentorship program at the University of British Columbia. This program allows me to give back to the computer science department while providing guidance to students concerning the direction of their coursework and careers. Not only have I found this experience to be rewarding, I have also made some lifelong friends over the years.

Education

2006 - 2009

Bachelor's Degree in Computer Science

The University of British Columbia - Vancouver, BC, Canada

Skills

Libraries/APIs

Selenium API, Selenium WebDriver, WebDriver, REST APIs, Playwright, Node.js, React

Tools

Confluence, Subversion (SVN), REST Assured, Microsoft Test Manager, TestRail, HP Quality Center (QC), Eclipse IDE, Jira, Cucumber, Zephyr, Postman, TortoiseSVN, TortoiseGit, Bitbucket, Jenkins, Microsoft Visual Studio, Git, Apache Maven, Microsoft Team Foundation Server, Phabricator, GitLab, GitHub, BrowserStack, Trello, VersionOne, Visual Studio, TFS, QTP, IE Developer Toolbar, pgAdmin, Perforce, HP QuickTest Professional (QTP), Bamboo, Xcode, Android Auto, Charles Proxy

Languages

XPath, Java, Python, CSS, Python 3, JavaScript, HTML, SQL, XML, TypeScript, C++, C#, C#.NET, Swift

Frameworks

Selenium, JUnit, TestNG, Appium, Protractor, Jasmine, XCUITest, Cypress, Swagger, NUnit, .NET

Paradigms

Software Testing, Functional Testing, Unit Testing, E2E Testing, Scrum, Testing, Automated Testing, Test Automation, Manual Testing, Agile, Automation, User Acceptance Testing (UAT), User Testing

Platforms

Android, iOS, TestLink, MacOS, Windows, WordPress, Oracle Database, Salesforce

Storage

Databases, Microsoft SQL Server, JSON, SQL Server Management Studio (SSMS)

Other

QA Testing, Web Service Testing, Test Automation Frameworks, Smoke Testing, White Box Testing, Regression Testing, Automated UI Testing, UI Testing, Integration Testing, System Testing, Exploratory Testing, Test Case Execution, Test Case Creation, Test Planning, Software Testing Lifecycle (STLC), Test Management, Android Testing, Test Analysis, Selenium PageFactory, Website QA, QA Leadership, Agile Software Testing, Website Testing, Web App Testing, Web-based Testing, Black Box Testing, Manual QA, Mobile App Testing, UI Automation, QA Automation, Software QA, Software Development Lifecycle (SDLC), Quality Assurance (QA), Test Cases, Selenium Page Object, Mobile Device QA Automation, SDET, Software Development, Mobile Apps, Leadership, Test Scripting, Test Scenarios, Agile QA, Testing Strategy, Cross-browser Testing, Manual Software Testing, Bug Discovery & Tracking, Documentation, Startups, Quality Control (QC), Test Documentation, QA Process, Validation, Web Accessibility, Team Foundation Server 2013, API Testing, APIs, CI/CD Pipelines, Accessibility Testing, Content Management Systems (CMS), Mandarin, Artificial Intelligence (AI), Data Migration Testing, Data Annotation, Data Labeling, AI Testing, PyUnit, Wave, Accessibility, JAWS, IIS, Cryptocurrency, Log4j, Agile Sprints, Fantasy Sports, Sports

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