Flashback is based on Betamax and was used by LinkedIn for testing third party websites.

LinkedIn, the social networking platform for professionals, has now open sourced Flashback, a proxy server application that helps in recording, storing and replaying internet transactions for developer testing.

Flashback tool is used for mocking internet traffic for developer testing, when web applications are being developed which needed interaction with third-party websites.

LinkedIn stated that Flashback tool was developed by Shangshang Feng, Yabin Kang, and Dan Vinegrad to test reliability, scalability and speed on new code before wide application.

It is based on Betamax, a tool developed to mock actions (record and replay) of web services and REST APIs used by developers.

According to LinkedIn, it develops web applications which need to interact with third party websites, hence it uses automatic testing that ensures quality of testing.

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