INTERACTIVE DEMO / COUPON BUG
Replay the failure.
Verify the fix.
A $24 cart. A $100 coupon. A −$76 total.
Experience Capture → Replay → Fix → Verify in about a minute.
Deterministic sample · runs locally in your browser. This illustrative model executes sample JavaScript, not the BugCapsule SDK. All data is synthetic. No signup, installation or API requests.
- 01 Capture
- 02 Replay
- 03 Fix
- 04 Verify
- 05 Summary
Sample application
WEB / JAVASCRIPTEveryday canvas tote
$24.00Natural canvas · made for the everyday
- Screen
- product
- Cart
- 0 items
- Coupon
- SAVE100 · ready to apply
- Subtotal
- $0.00
- Applied discount
- $0.00
- Total
- $0.00
Capsule inspector
CAPTURINGcoupon-negative-total-v11 / 6 eventsSelected event · Restore empty cart
Same coupon. A total that makes sense.
SAMPLE CODE CHANGEThe original calculation subtracts $100 from a $24 subtotal. Clamp the result at zero so the applied discount cannot exceed the subtotal. This is a prepared sample fix, not an automatically generated production patch.
BEFORE Unbounded discount
AFTER Clamp at zero
Verification evidence
3 ATTEMPTS / RUNBefore and after the fix, each attempt starts with an empty cart and runs the same six steps with SAVE100. Only the calculation changes. Durations measure local model execution, not production replay.
Before fix
After fix
SCENARIO OUTCOME
Evidence for this synthetic scenario only. This does not prove the application is regression-free or that the issue can never recur.
Ready to reproduce bugs in your own app?
01 / Capture the failure
Use the sample app. Each action becomes inspectable evidence.
Want actual SDK execution? Run the SDK coupon scenario locally ↗. Requires the CLI, Chromium and a BugCapsule project.