What is canary deployment?

Canary Deployment is a software release strategy. It involves rolling out new features or updates to a small subset of users before a full-scale deployment. This approach helps identify and fix issues early, minimizing the risk of widespread problems.

First, you roll out updates to a small user group. This gradual rollout allows you to monitor the new feature in a controlled setting. If any bugs appear, you catch them early. This early detection is crucial for maintaining system stability.

You also gather valuable feedback from this initial user group. Their reactions and experiences provide insights into the new feature's performance. This feedback loop helps you refine the feature before expanding the rollout.

To sum up, Canary Deployment involves:

• Gradual rollout to a small user group.

• Early detection of bugs.

• User feedback on new features.

Key benefits of canary deployment

Reduced Risk: Rolling out to a small group limits potential issues. You can address problems early, avoiding widespread impact. This concept is central to canary testing, which aims to detect potential issues before they affect the entire user base.

User Feedback: Early adopters share insights. Their feedback helps refine features before a wider release. This aligns with the practice of canary launch, which involves introducing new features to a limited user subset before a full rollout.

Easier Rollback: Detecting major issues early makes rollbacks simpler. Fewer users are affected, minimizing disruption. According to feature flag best practices, it's crucial to identify issues early and use metric-based evidence to decide whether to release more broadly or roll back.

Canary deployment ensures smoother updates. You test with a limited audience, catching bugs early. This strategy enhances software quality and user satisfaction.

How canary deployment works

1. Duplicate infrastructure: Set up a new environment parallel to the existing one. This includes all necessary components to mirror production. For more on how this fits within the broader concept, see Canary Testing.

2. Feature flags: Control visibility of features. Enable or disable them seamlessly. Learn more about Feature Flags Best Practices and their role in canary deployments.

3. Group selection: Choose a small user subset or specific servers. This group tests the new features first. This is akin to selecting a "canary" group in a Canary Launch.

4. Load balancers: Route traffic between production and the canary environment. This ensures a smooth transition. For detailed steps on managing traffic, refer to How Statsig Works.

5. Gradual rollout: Start with the canary group. Expand to the full user base if everything works well. This gradual approach is detailed in the Canary Launch strategy.

Examples of canary deployment

Example 1: social media platform

A social media company releases a new photo-sharing feature to 5% of its users. User feedback and system performance are monitored closely. If successful, the feature is gradually rolled out to all users.

Example 2: e-commerce website

An e-commerce site introduces a new checkout process to a small user group. User behavior and performance metrics are analyzed. Once confirmed smooth, the process expands to all users.

Example 3: mobile app update

A mobile app developer releases an update to a fraction of users. Data on app crashes and user experience are collected. The update is then rolled out to all users if stable.