Google takes testing seriously:
To that end, Google employs a four-stage testing process for changes to the search engine, consisting of:
Testing by dedicated, internal testers (Google employees)
Further testing on a crowdtesting platform
“Dogfooding,” which involves having Google employees use the product in their daily work
Beta testing, which involves releasing the product to a small group of Google product end users
Facebook: Developer-driven testing
Facebook employs a wide variety of automated testing solutions. The tools that are used range from PHPUnit for back-end unit testing to Jest (a JavaScript test tool developed internally at Facebook) to Watir for end-to-end testing efforts.
Amazon: Deployment comes first
The feeling at Amazon is that its development and deployment processes are so mature (the company famously deploys software every 11.6 seconds!) that there is no need for elaborate and extensive testing efforts. It is all about making software easy to deploy, and, equally if not more important, easy to roll back in case of a failure.
Spotify: Squads, tribes and chapters
Testing at Spotify is taken very seriously. Just like programming, testing is considered a creative process, and something that cannot be (fully) automated. Contrary to most other companies mentioned in this article, Spotify heavily relies on dedicated testers that explore and evaluate the product, instead of trying to automate as much as possible.
Microsoft: Engineers and testers are one
Microsoft’s ratio of testers to developers is currently around 2:3 (SDETs)
Source: 5 effective and powerful ways to test like tech giants: https://bit.ly/2nkjIvy