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How Are Events Tracked?

Manually track user actions in FlagSync via the track() function, providing the core data that all Metrics rely on for analysis.

client.track(
  eventKey: string,
  eventValue?: number | null,
  properties?: Record<string, any> | null
);

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Tracking Event Types

There are two types of events:

Numeric

Captures measurable data like time or counts.

Property

Captures rich context like purchase details.

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Numeric Events

Use eventValue to capture measurable data like time or counts for Numeric Metrics:

// Track page load time in seconds
client.track('page_load_time', 1.42);

Why

Perfect for metrics like “Average Page Load Time”—tracks quantifiable outcomes for analysis.

Use Case

Test if a feature slows or improves your app—send this event, then review the average in Metrics.

Example

A developer might track load times across a new UI—e.g., 1.42s—to ensure performance holds.

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Property Events

Use properties to capture rich context like purchase details for detailed Numeric Metrics:

const purchase = {
  productId: '0x123',
  price: 49.99,
  discount: 0.20,
  isReturningUser: true,
};

client.track('purchase_event', null, purchase);

Why

Allows the creation of multiple Numeric Metrics (e.g., “Average Purchase Price” from price, “Discount Usage” from discount) from one purchase_event.

Use Case

Test if a feature increases purchase amounts or targets returning users—analyze in Metrics.

Example

Track a purchase_event to check if a 20% discount boosts $49.99 purchases or engages returning buyers.

Why not just use price as the eventValue?

Properties let you track one purchase_event and create separate metrics for price, discount, or other keys—more flexibility than a single number.

See Metric Examples for more detail.

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Best Practices

  • Name Clearly: Use descriptive event keys (e.g., signup-cta-click) to match metrics.
  • Limit Data: Include only relevant properties (e.g., price, discount) to avoid clutter.
  • Validate Early: Check events in Live Events before defining metrics.

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Next Steps