Activation engine
The activation engine tracks user activation milestones (Setup, Aha, Habit)
for personalization experiments on GitLab.com. It integrates with the
internal events
system through the extra_trackers mechanism, following the same pattern
used by AI tracking (ee/lib/gitlab/tracking/ai_tracking.rb) and
contribution analytics tracking (lib/gitlab/tracking/contribution_analytics_tracking.rb).
The activation engine is EE-only and gated behind the activation_tracking
feature flag (:wip type).
Architecture
When application code calls Gitlab::InternalEvents.track_event, the
internal events router reads the event YAML definition. If the definition
includes an extra_trackers entry for Gitlab::Tracking::ActivationTracking,
the router calls ActivationTracking.track_event. That adapter delegates
to Activation::Metric.track, which writes a record to the
activation_metrics table.
flowchart LR A["Gitlab::InternalEvents.track_event"] --> B["Event YAML<br/>(extra_trackers)"] B --> C["ActivationTracking.track_event"] C --> D["Activation::Metric.track"] D --> E["activation_metrics table"]
The activation_metrics table stores one record per user, per metric,
per namespace. A database-level unique constraint (with NULLS NOT DISTINCT)
prevents duplicate records.
| Component | Path | Purpose |
|---|---|---|
| Tracking adapter | ee/lib/gitlab/tracking/activation_tracking.rb | Receive events from the Internal Events router and delegate to the model. |
| Event definition | ee/config/events/merged_mr.yml | Declare extra_trackers to wire an internal event to activation tracking. |
| Model | ee/app/models/activation/metric.rb | Record, query, and check activation metrics. |
| Finder | ee/app/finders/activation/metrics_finder.rb | Filter metrics by user, namespace, and metric type. |
| Feature flag | ee/config/feature_flags/wip/activation_tracking.yml | Controls whether tracking is active. |
| Factory | ee/spec/factories/activation/metrics.rb | Test factory for activation_metric. |
Available metric types
Metric types are defined in the Activation::Metric enum. Each enum value
corresponds to an internal event name routed through ActivationTracking.
For example, the merged_mr event defined in
ee/config/events/merged_mr.yml maps to the merged_mr enum value.
enum :metric, {
merged_mr: 0
}To add a new metric type, see the quick start guide.