Understand the failure.
Verify the repair.
Small, reproducible software failures. The broken implementation, the fix that didn’t work, and the one that passed—preserved together.
Explore the cases ↓How results are verified ↗WHAT THE ARCHIVE CONTAINS
100840 executable cases. 20168 are open.
Every case records the implementation that fails, the fix that did not work, and the repair that passed its checks—with recorded outputs and source hashes. This release adds 100840 cases across 20168 failure mechanisms and 254 domains.
The open tier gives you the failure and the unsuccessful fix for one case in every mechanism. The remaining 80672 cases, 5 variants per mechanism, are member-only: the verified repair, its recorded checks, and the full fixture suite are held in the member archive. Read the methodology ↗
A RECORD OF WHAT WENT WRONG
Browse the archive / 100840
Bag of exactly 23 kg charged as overweight · case 01
A bag weighing exactly the free weight limit incurs the 100 surcharge.
Bag of exactly 23 kg charged as overweight · case 02
A bag weighing exactly the free weight limit incurs the 100 surcharge.
Bag of exactly 23 kg charged as overweight · case 03
A bag weighing exactly the free weight limit incurs the 100 surcharge.
Bag of exactly 23 kg charged as overweight · case 04
A bag weighing exactly the free weight limit incurs the 100 surcharge.
Bag of exactly 23 kg charged as overweight · case 05
A bag weighing exactly the free weight limit incurs the 100 surcharge.
Bags within the free allowance escape the 32 kg maximum · case 01
A 33 kg first bag on a fare with one free piece is accepted and priced.
Bags within the free allowance escape the 32 kg maximum · case 02
A 33 kg first bag on a fare with one free piece is accepted and priced.
Bags within the free allowance escape the 32 kg maximum · case 03
A 33 kg first bag on a fare with one free piece is accepted and priced.
Bags within the free allowance escape the 32 kg maximum · case 04
A 33 kg first bag on a fare with one free piece is accepted and priced.
Bags within the free allowance escape the 32 kg maximum · case 05
A 33 kg first bag on a fare with one free piece is accepted and priced.
Elite benefit replaces the fare allowance · case 01
An elite traveller on a two-bag fare only gets one free bag.
Elite benefit replaces the fare allowance · case 02
An elite traveller on a two-bag fare only gets one free bag.
Elite benefit replaces the fare allowance · case 03
An elite traveller on a two-bag fare only gets one free bag.
Elite benefit replaces the fare allowance · case 04
An elite traveller on a two-bag fare only gets one free bag.
Elite benefit replaces the fare allowance · case 05
An elite traveller on a two-bag fare only gets one free bag.
Overweight surcharge waived for free bags · case 01
A 28 kg bag within the free allowance goes through without the weight surcharge.
Overweight surcharge waived for free bags · case 02
A 28 kg bag within the free allowance goes through without the weight surcharge.
Overweight surcharge waived for free bags · case 03
A 28 kg bag within the free allowance goes through without the weight surcharge.
Overweight surcharge waived for free bags · case 04
A 28 kg bag within the free allowance goes through without the weight surcharge.
Overweight surcharge waived for free bags · case 05
A 28 kg bag within the free allowance goes through without the weight surcharge.
Commencement window applied to the return date · case 01
A trip that starts inside the travel window but returns after it fails COMMENCE.
Commencement window applied to the return date · case 02
A trip that starts inside the travel window but returns after it fails COMMENCE.
Commencement window applied to the return date · case 03
A trip that starts inside the travel window but returns after it fails COMMENCE.
Commencement window applied to the return date · case 04
A trip that starts inside the travel window but returns after it fails COMMENCE.
Commencement window applied to the return date · case 05
A trip that starts inside the travel window but returns after it fails COMMENCE.
Tickets sold on the final sale day rejected · case 01
Sales on the advertised last day of the promotion fail.
Tickets sold on the final sale day rejected · case 02
Sales on the advertised last day of the promotion fail.
Tickets sold on the final sale day rejected · case 03
Sales on the advertised last day of the promotion fail.
Tickets sold on the final sale day rejected · case 04
Sales on the advertised last day of the promotion fail.
Tickets sold on the final sale day rejected · case 05
Sales on the advertised last day of the promotion fail.
Return on the completion date flagged late · case 01
Travel completed exactly on the deadline fails COMPLETE.
Return on the completion date flagged late · case 02
Travel completed exactly on the deadline fails COMPLETE.
Return on the completion date flagged late · case 03
Travel completed exactly on the deadline fails COMPLETE.
Return on the completion date flagged late · case 04
Travel completed exactly on the deadline fails COMPLETE.
Return on the completion date flagged late · case 05
Travel completed exactly on the deadline fails COMPLETE.
Travel window checked against the sale date · case 01
Tickets sold before the travel window opens always fail COMMENCE.
Travel window checked against the sale date · case 02
Tickets sold before the travel window opens always fail COMMENCE.
Travel window checked against the sale date · case 03
Tickets sold before the travel window opens always fail COMMENCE.
Travel window checked against the sale date · case 04
Tickets sold before the travel window opens always fail COMMENCE.
Travel window checked against the sale date · case 05
Tickets sold before the travel window opens always fail COMMENCE.
Route request admission: path occupancy scope · case 01
A route is granted into a section that already holds a train.
Route request admission: path occupancy scope · case 02
A route is granted into a section that already holds a train.
Route request admission: path occupancy scope · case 03
A route is granted into a section that already holds a train.
Route request admission: path occupancy scope · case 04
A route is granted into a section that already holds a train.
Route request admission: path occupancy scope · case 05
A route is granted into a section that already holds a train.
Route request admission: shared point agreement · case 01
Compatible routes that use a common point in the same lie are refused.
Route request admission: shared point agreement · case 02
Compatible routes that use a common point in the same lie are refused.
Route request admission: shared point agreement · case 03
Compatible routes that use a common point in the same lie are refused.
Route request admission: shared point agreement · case 04
Compatible routes that use a common point in the same lie are refused.
Route request admission: shared point agreement · case 05
Compatible routes that use a common point in the same lie are refused.
Route request admission: opposing detection scope · case 01
Routes in the opposite direction anywhere on the layout block each other and opposing routes are misreported.
Route request admission: opposing detection scope · case 02
Routes in the opposite direction anywhere on the layout block each other and opposing routes are misreported.
Route request admission: opposing detection scope · case 03
Routes in the opposite direction anywhere on the layout block each other and opposing routes are misreported.
Route request admission: opposing detection scope · case 04
Routes in the opposite direction anywhere on the layout block each other and opposing routes are misreported.
Route request admission: opposing detection scope · case 05
Routes in the opposite direction anywhere on the layout block each other and opposing routes are misreported.
Route request admission: re-request of a set route · case 01
Re-requesting a route that is already set reports a conflict with itself.
Route request admission: re-request of a set route · case 02
Re-requesting a route that is already set reports a conflict with itself.
Route request admission: re-request of a set route · case 03
Re-requesting a route that is already set reports a conflict with itself.
Route request admission: re-request of a set route · case 04
Re-requesting a route that is already set reports a conflict with itself.
Route request admission: re-request of a set route · case 05
Re-requesting a route that is already set reports a conflict with itself.
Route request admission: overlap conflict geometry · case 01
A route is granted whose path runs through the overlap of a locked route (or the reverse).
Route request admission: overlap conflict geometry · case 02
A route is granted whose path runs through the overlap of a locked route (or the reverse).
Route request admission: overlap conflict geometry · case 03
A route is granted whose path runs through the overlap of a locked route (or the reverse).
Route request admission: overlap conflict geometry · case 04
A route is granted whose path runs through the overlap of a locked route (or the reverse).
Route request admission: overlap conflict geometry · case 05
A route is granted whose path runs through the overlap of a locked route (or the reverse).
Four-aspect signal chain evaluation: dark signal treatment · case 01
The signal in rear of a dark signal shows a proceed aspect.
Four-aspect signal chain evaluation: dark signal treatment · case 02
The signal in rear of a dark signal shows a proceed aspect.
Four-aspect signal chain evaluation: dark signal treatment · case 03
The signal in rear of a dark signal shows a proceed aspect.
Four-aspect signal chain evaluation: dark signal treatment · case 04
The signal in rear of a dark signal shows a proceed aspect.
Four-aspect signal chain evaluation: dark signal treatment · case 05
The signal in rear of a dark signal shows a proceed aspect.
Four-aspect signal chain evaluation: failed filament scope · case 01
Signals with a failed red filament go dark even while showing a proceed aspect.
Four-aspect signal chain evaluation: failed filament scope · case 02
Signals with a failed red filament go dark even while showing a proceed aspect.
Four-aspect signal chain evaluation: failed filament scope · case 03
Signals with a failed red filament go dark even while showing a proceed aspect.
Four-aspect signal chain evaluation: failed filament scope · case 04
Signals with a failed red filament go dark even while showing a proceed aspect.
Four-aspect signal chain evaluation: failed filament scope · case 05
Signals with a failed red filament go dark even while showing a proceed aspect.
Four-aspect signal chain evaluation: diverging aspect cap · case 01
A diverging junction signal displays a preliminary caution or green.
Four-aspect signal chain evaluation: diverging aspect cap · case 02
A diverging junction signal displays a preliminary caution or green.
Four-aspect signal chain evaluation: diverging aspect cap · case 03
A diverging junction signal displays a preliminary caution or green.
Four-aspect signal chain evaluation: diverging aspect cap · case 04
A diverging junction signal displays a preliminary caution or green.
Four-aspect signal chain evaluation: diverging aspect cap · case 05
A diverging junction signal displays a preliminary caution or green.
Four-aspect signal chain evaluation: line end boundary · case 01
The last signal before a buffer stop shows green.
Four-aspect signal chain evaluation: line end boundary · case 02
The last signal before a buffer stop shows green.
Four-aspect signal chain evaluation: line end boundary · case 03
The last signal before a buffer stop shows green.
Four-aspect signal chain evaluation: line end boundary · case 04
The last signal before a buffer stop shows green.
Four-aspect signal chain evaluation: line end boundary · case 05
The last signal before a buffer stop shows green.
Four-aspect signal chain evaluation: preliminary caution step · case 01
A signal two blocks behind a red shows green instead of double yellow.
Four-aspect signal chain evaluation: preliminary caution step · case 02
A signal two blocks behind a red shows green instead of double yellow.
Four-aspect signal chain evaluation: preliminary caution step · case 03
A signal two blocks behind a red shows green instead of double yellow.
Four-aspect signal chain evaluation: preliminary caution step · case 04
A signal two blocks behind a red shows green instead of double yellow.
Four-aspect signal chain evaluation: preliminary caution step · case 05
A signal two blocks behind a red shows green instead of double yellow.
Point machine throw control: refusal alarm · case 01
A locked point without detection raises no alarm, or a healthy locked point raises one.
Point machine throw control: refusal alarm · case 02
A locked point without detection raises no alarm, or a healthy locked point raises one.
Point machine throw control: refusal alarm · case 03
A locked point without detection raises no alarm, or a healthy locked point raises one.
Point machine throw control: refusal alarm · case 04
A locked point without detection raises no alarm, or a healthy locked point raises one.
Point machine throw control: refusal alarm · case 05
A locked point without detection raises no alarm, or a healthy locked point raises one.
Point machine throw control: detection deadline boundary · case 01
A point detected exactly at the deadline is declared failed.
Point machine throw control: detection deadline boundary · case 02
A point detected exactly at the deadline is declared failed.
Point machine throw control: detection deadline boundary · case 03
A point detected exactly at the deadline is declared failed.
Point machine throw control: detection deadline boundary · case 04
A point detected exactly at the deadline is declared failed.
Point machine throw control: detection deadline boundary · case 05
A point detected exactly at the deadline is declared failed.
INSPECTABLE BY DESIGN
Every result has a runnable source.
Runnable implementations with recorded outputs, source hashes, and explicit contracts. Related variants share a failure mechanism and belong together in evaluation splits.
Read the methodology ↗