Canary Deployment

What is canary deployment?

Canary deployment is the delivery of new software features to a subset of users (say 5 to 10 percent) or specific servers before being released to a wider audience. This helps development and product teams learn and test on a batch of users acting as a "canary" or warning sign for issues.

Why is it called canary deployment?

In the early 1900s, coal miners would bring canaries into mines with them as a warning indicator for carbon monoxide and other dangerous gases. It's a little dark, but canaries are sensitive to poisonous gas so if they were to become affected by the gas, it was a sign that the miners needed to evacuate.

In canary deployment, teams deploy to a subset of users or on a specific server to test it before going to the large audience. This test group acts as the canary to warn teams of any potential issues.

Why is canary deployment important?

With the speed that teams are developing today, it's better to be safe than sorry. Using a small percentage of users or servers as a "canary"  before launching their product or releasing new features to their entire customer base gives teams peace of mind. 

Here are some of the benefits of using canary deployment:

• More confidence in release stability
• Identify major issues before it hits scale
• Avoid large scale negative feedback or publicity
• Reduce risk by maintaining a strategy for rolling back versions if issues are discovered