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
Level crossing warning timeline: crossing proving point · case 01
A four-quadrant crossing is proven before its exit barriers are down.
Level crossing warning timeline: crossing proving point · case 02
A four-quadrant crossing is proven before its exit barriers are down.
Level crossing warning timeline: crossing proving point · case 03
A four-quadrant crossing is proven before its exit barriers are down.
Level crossing warning timeline: crossing proving point · case 04
A four-quadrant crossing is proven before its exit barriers are down.
Level crossing warning timeline: crossing proving point · case 05
A four-quadrant crossing is proven before its exit barriers are down.
Level crossing warning timeline: obstacle confirmation · case 01
The protecting signal clears although the obstacle detector never confirmed the crossing empty.
Level crossing warning timeline: obstacle confirmation · case 02
The protecting signal clears although the obstacle detector never confirmed the crossing empty.
Level crossing warning timeline: obstacle confirmation · case 03
The protecting signal clears although the obstacle detector never confirmed the crossing empty.
Level crossing warning timeline: obstacle confirmation · case 04
The protecting signal clears although the obstacle detector never confirmed the crossing empty.
Level crossing warning timeline: obstacle confirmation · case 05
The protecting signal clears although the obstacle detector never confirmed the crossing empty.
Level crossing warning timeline: warning time reference · case 01
The road warning time is overstated.
Level crossing warning timeline: warning time reference · case 02
The road warning time is overstated.
Level crossing warning timeline: warning time reference · case 03
The road warning time is overstated.
Level crossing warning timeline: warning time reference · case 04
The road warning time is overstated.
Level crossing warning timeline: warning time reference · case 05
The road warning time is overstated.
Level crossing warning timeline: sighting margin · case 01
The crossing is judged safe although the driver cannot see the signal clear in time.
Level crossing warning timeline: sighting margin · case 02
The crossing is judged safe although the driver cannot see the signal clear in time.
Level crossing warning timeline: sighting margin · case 03
The crossing is judged safe although the driver cannot see the signal clear in time.
Level crossing warning timeline: sighting margin · case 04
The crossing is judged safe although the driver cannot see the signal clear in time.
Level crossing warning timeline: sighting margin · case 05
The crossing is judged safe although the driver cannot see the signal clear in time.
Overlap timed release: timer expiry boundary · case 01
The overlap stays locked at the exact moment the timer expires.
Overlap timed release: timer expiry boundary · case 02
The overlap stays locked at the exact moment the timer expires.
Overlap timed release: timer expiry boundary · case 03
The overlap stays locked at the exact moment the timer expires.
Overlap timed release: timer expiry boundary · case 04
The overlap stays locked at the exact moment the timer expires.
Overlap timed release: timer expiry boundary · case 05
The overlap stays locked at the exact moment the timer expires.
Overlap timed release: timer start latch · case 01
A bobbing berth track circuit keeps pushing the overlap release back.
Overlap timed release: timer start latch · case 02
A bobbing berth track circuit keeps pushing the overlap release back.
Overlap timed release: timer start latch · case 03
A bobbing berth track circuit keeps pushing the overlap release back.
Overlap timed release: timer start latch · case 04
A bobbing berth track circuit keeps pushing the overlap release back.
Overlap timed release: timer start latch · case 05
A bobbing berth track circuit keeps pushing the overlap release back.
Overlap timed release: berth clear cancellation · case 01
The overlap is released after the train has already left the berth.
Overlap timed release: berth clear cancellation · case 02
The overlap is released after the train has already left the berth.
Overlap timed release: berth clear cancellation · case 03
The overlap is released after the train has already left the berth.
Overlap timed release: berth clear cancellation · case 04
The overlap is released after the train has already left the berth.
Overlap timed release: berth clear cancellation · case 05
The overlap is released after the train has already left the berth.
Overlap timed release: overrun blocking · case 01
The overlap is released while the train stands in it.
Overlap timed release: overrun blocking · case 02
The overlap is released while the train stands in it.
Overlap timed release: overrun blocking · case 03
The overlap is released while the train stands in it.
Overlap timed release: overrun blocking · case 04
The overlap is released while the train stands in it.
Overlap timed release: overrun blocking · case 05
The overlap is released while the train stands in it.
Absolute block bell-code working: clearing point condition · case 01
Line clear is given while the clearing point beyond the home signal is fouled.
Absolute block bell-code working: clearing point condition · case 02
Line clear is given while the clearing point beyond the home signal is fouled.
Absolute block bell-code working: clearing point condition · case 03
Line clear is given while the clearing point beyond the home signal is fouled.
Absolute block bell-code working: clearing point condition · case 04
Line clear is given while the clearing point beyond the home signal is fouled.
Absolute block bell-code working: clearing point condition · case 05
Line clear is given while the clearing point beyond the home signal is fouled.
Absolute block bell-code working: departure authority · case 01
A second train entering an occupied block raises no alarm.
Absolute block bell-code working: departure authority · case 02
A second train entering an occupied block raises no alarm.
Absolute block bell-code working: departure authority · case 03
A second train entering an occupied block raises no alarm.
Absolute block bell-code working: departure authority · case 04
A second train entering an occupied block raises no alarm.
Absolute block bell-code working: departure authority · case 05
A second train entering an occupied block raises no alarm.
Absolute block bell-code working: tail lamp check · case 01
The block is released although the train arrived without its tail lamp.
Absolute block bell-code working: tail lamp check · case 02
The block is released although the train arrived without its tail lamp.
Absolute block bell-code working: tail lamp check · case 03
The block is released although the train arrived without its tail lamp.
Absolute block bell-code working: tail lamp check · case 04
The block is released although the train arrived without its tail lamp.
Absolute block bell-code working: tail lamp check · case 05
The block is released although the train arrived without its tail lamp.
Absolute block bell-code working: cancel scope · case 01
Cancelling a block with a train in it frees the section.
Absolute block bell-code working: cancel scope · case 02
Cancelling a block with a train in it frees the section.
Absolute block bell-code working: cancel scope · case 03
Cancelling a block with a train in it frees the section.
Absolute block bell-code working: cancel scope · case 04
Cancelling a block with a train in it frees the section.
Absolute block bell-code working: cancel scope · case 05
Cancelling a block with a train in it frees the section.
ATP braking curve supervision: safety margin · case 01
The permitted speed is supervised against the danger point rather than the margin-reduced target.
ATP braking curve supervision: safety margin · case 02
The permitted speed is supervised against the danger point rather than the margin-reduced target.
ATP braking curve supervision: safety margin · case 03
The permitted speed is supervised against the danger point rather than the margin-reduced target.
ATP braking curve supervision: safety margin · case 04
The permitted speed is supervised against the danger point rather than the margin-reduced target.
ATP braking curve supervision: safety margin · case 05
The permitted speed is supervised against the danger point rather than the margin-reduced target.
ATP braking curve supervision: line speed ceiling · case 01
The permitted speed exceeds the line speed far from the target.
ATP braking curve supervision: line speed ceiling · case 02
The permitted speed exceeds the line speed far from the target.
ATP braking curve supervision: line speed ceiling · case 03
The permitted speed exceeds the line speed far from the target.
ATP braking curve supervision: line speed ceiling · case 04
The permitted speed exceeds the line speed far from the target.
ATP braking curve supervision: line speed ceiling · case 05
The permitted speed exceeds the line speed far from the target.
ATP braking curve supervision: permitted speed rounding · case 01
The permitted speed is one km/h above the braking curve.
ATP braking curve supervision: permitted speed rounding · case 02
The permitted speed is one km/h above the braking curve.
ATP braking curve supervision: permitted speed rounding · case 03
The permitted speed is one km/h above the braking curve.
ATP braking curve supervision: permitted speed rounding · case 04
The permitted speed is one km/h above the braking curve.
ATP braking curve supervision: permitted speed rounding · case 05
The permitted speed is one km/h above the braking curve.
ATP braking curve supervision: intervention precedence · case 01
A train far over the curve only gets a warning.
ATP braking curve supervision: intervention precedence · case 02
A train far over the curve only gets a warning.
ATP braking curve supervision: intervention precedence · case 03
A train far over the curve only gets a warning.
ATP braking curve supervision: intervention precedence · case 04
A train far over the curve only gets a warning.
ATP braking curve supervision: intervention precedence · case 05
A train far over the curve only gets a warning.
ATP braking curve supervision: warning threshold boundary · case 01
A train running exactly at the warning margin is warned.
ATP braking curve supervision: warning threshold boundary · case 02
A train running exactly at the warning margin is warned.
ATP braking curve supervision: warning threshold boundary · case 03
A train running exactly at the warning margin is warned.
ATP braking curve supervision: warning threshold boundary · case 04
A train running exactly at the warning margin is warned.
ATP braking curve supervision: warning threshold boundary · case 05
A train running exactly at the warning margin is warned.
Movement authority end computation: scan start · case 01
The train is given no authority because its own section blocks the scan.
Movement authority end computation: scan start · case 02
The train is given no authority because its own section blocks the scan.
Movement authority end computation: scan start · case 03
The train is given no authority because its own section blocks the scan.
Movement authority end computation: scan start · case 04
The train is given no authority because its own section blocks the scan.
Movement authority end computation: scan start · case 05
The train is given no authority because its own section blocks the scan.
Movement authority end computation: blocking section boundary · case 01
The authority extends through the blocking section.
Movement authority end computation: blocking section boundary · case 02
The authority extends through the blocking section.
Movement authority end computation: blocking section boundary · case 03
The authority extends through the blocking section.
Movement authority end computation: blocking section boundary · case 04
The authority extends through the blocking section.
Movement authority end computation: blocking section boundary · case 05
The authority extends through the blocking section.
Movement authority end computation: length cap reference · case 01
The authority is cut short of max_ma_m ahead of the train.
Movement authority end computation: length cap reference · case 02
The authority is cut short of max_ma_m ahead of the train.
Movement authority end computation: length cap reference · case 03
The authority is cut short of max_ma_m ahead of the train.
Movement authority end computation: length cap reference · case 04
The authority is cut short of max_ma_m ahead of the train.
Movement authority end computation: length cap reference · case 05
The authority is cut short of max_ma_m ahead of the train.
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 ↗