Feature Flags

Feature flags are the foundation of Supaship. They let you control features at runtime without redeploying code. With flags, you can roll out safely, test with real users, and respond instantly if something breaks.

What are Feature Flags?

Feature flags are switches in your code that Supaship controls remotely. Instead of hardcoding whether a feature is on or off, you check the flag value at runtime.


const isEnabled = await client.getFeature('new-checkout-flow')
 
if (isEnabled) {
  renderNewCheckout() // New feature
} else {
  renderOldCheckout()
}

Why use them?

Ship code safely – Deploy features disabled, enable when ready
Test in production – Enable for specific users or percentages
Instant rollbacks – Turn off broken features without redeploying
Gradual rollouts – Start with 1%, increase to 100% over time

Creating a Feature Flag

Go to your project and click “Create Feature Flag”
Enter a name (lowercase, numbers, hyphens only) – e.g., new-checkout-flow
Choose a type: Boolean (on/off) or JSON (structured data)
Click “Create”

After creation, configure targeting rules to control who sees the feature.

Flag Types

Boolean Flags

Simple true/false switches for enabling or disabling features.


const isEnabled = await client.getFeature('beta-banner')
 
if (isEnabled) {
  showBetaBanner()
}

Use cases: Toggle features, beta banners, A/B tests

JSON Flags

Return structured data for complex configurations.


const config = await client.getFeature('api-config')
 
const apiClient = new ApiClient(config)

Use cases: API configurations, feature settings, experiment parameters

Note: Need string or number values? Use a JSON flag with a single property.

Best Practices

Naming Conventions

Use descriptive, lowercase names with hyphens
Use a period to group related flags
Examples: new-checkout-flow, beta-features, dark-mode

Monitoring and Analytics

Track Feature Usage

Monitor how your features are being used:

Real-time metrics - Live feature usage data
User engagement - Track how features affect behavior
Performance monitoring - Monitor flag evaluation times
Custom events - Track specific user actions