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Test driven development
unit tests
to ensure that every time changes are made the system reports any errors on tests
Good definition here: What is Test Driven Development (TDD)? | Agile Alliance
Automated Testing
Egor QA testing with Postman
What else do we need?
QA Regression./Automation
QA Automation Engineer
Integrated regression testing to check the overall system is not affected by changes to the system
User interface testing as automated as possible in order to show resulting errors
Selenium, or something like it:
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