What role does a canary play in software development?

Canary testing is a form of beta testing an update for software. So canary testing allows the update to be released to a smaller audience and tests it to make sure the new code does not cause any problems. The term comes from when canaries were used in mining to let people know the air was unsafe. The canaries were very sensitive to toxic gases, so if they died, the miners would have enough time to escape the mine.

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