How rollout works

When a flag is of type rollout, CanaryGate determines whether a specific user should see the feature based on:

1. The user’s userId (passed in the SDK options or implicit)
2. The flag key (key)
3. The percentage configured in the dashboard

The calculation uses a deterministic hash: the same user with the same userId will always receive the same result for the same percentage. This ensures stickiness — the user does not alternate between versions.

Configuring in the SDK

const canary = new CanaryGate('cg_api_key', {
  userId: currentUser.id // or a stable anonymous string
})
await canary.init()
 
const flag = canary.getFlag('new-dashboard')
if (flag?.enabled) {
  // this user is in the rollout
}

Increasing the percentage

Typical canary deploy workflow:

Each percentage adjustment is delivered in real time via SSE to all connected clients.

Manual vs automatic rollout

• Manual: You adjust the percentage manually through the dashboard
• Automatic (Pro plan): Configure a schedule that increases the percentage automatically at defined times

See Schedule and Auto-rollout for more details.