Champion / Challenger
A/B experiments on live production decisions
Route a configurable percentage of live traffic to a challenger ruleset — no gateway changes, no code deploy. Compare APPROVE rates, latency, and budget spend in the decision warehouse before making a promotion decision.
How traffic splitting works
Traffic routing happens inside the execution runtime — not at an upstream proxy or gateway layer. This means no infrastructure changes and no cold-start penalty.
- 1
Configure experiment
In the Decision Server console, select the challenger ruleset version, set a traffic allocation (e.g., 10%), and define an observation window.
- 2
Governance check
The challenger ruleset must be in `approved` state. You cannot route live traffic to a draft or in-review version.
- 3
Live traffic splits
The runtime routes the configured percentage to the challenger. Both variants execute fully and write to the decision warehouse.
- 4
Compare KPIs
Decision Server shows per-variant KPI streams: decisions routed, latency, error rate, APPROVE/DECLINE/REVIEW distribution.
- 5
Promote or retire
When the sample is sufficient, promote the challenger to champion through the same review → approved → published governance workflow.
Example warehouse KPI comparison
| Metric | Champion — v11 (90%) | Challenger — v12 (10%) |
|---|---|---|
| Decisions routed | 89,432 | 10,568 |
| Mean latency | 3.4 ms | 3.7 ms |
| APPROVE rate | 62.1% | 64.3% ↑ +2.2pp |
| ENGINE_BUDGET_EXCEEDED | 0.002% | 0.003% |
| Mean steps spent | 2,841 | 3,102 |
Illustrative sample data — not real customer traffic. Both variants always write to the warehouse with variant tag.
Governance is not bypassed
A challenger ruleset must be in approved state before receiving live traffic. The promotion to champion also requires a reviewer signature through the standard governance lifecycle — the same workflow as any other version promotion. No shortcut for A/B experiments.
Run your first champion/challenger experiment
Available on Starter, Business, and Custom plans. Start a trial to evaluate.