LINE DEVELOPER DAY 2017 B-6 "Since web UI integration test takes time on implementation, execution, and maintenance; we parallelized test suites with scalable test executors in CI pipeline. With containerized test executors, the test suites can be executed on any platforms without library dependencies. To perform a parallel execution, we used docker-based Selenium grid - Zalenium to scale nodes dynamically. In this talk, we will show the architecture of testing with Docker containers and demonstrate how we make Selenium test faster and flexible in CI."