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
Making a doubled contract earns no insult · case 01
Doubled makes are 50 short.
Making a doubled contract earns no insult · case 02
Doubled makes are 50 short.
Making a doubled contract earns no insult · case 03
Doubled makes are 50 short.
Making a doubled contract earns no insult · case 04
Doubled makes are 50 short.
Making a doubled contract earns no insult · case 05
Doubled makes are 50 short.
Vulnerable small slams get the non-vulnerable bonus · case 01
6S vulnerable made is 250 short.
Vulnerable small slams get the non-vulnerable bonus · case 02
6S vulnerable made is 250 short.
Vulnerable small slams get the non-vulnerable bonus · case 03
6S vulnerable made is 250 short.
Vulnerable small slams get the non-vulnerable bonus · case 04
6S vulnerable made is 250 short.
Vulnerable small slams get the non-vulnerable bonus · case 05
6S vulnerable made is 250 short.
Vulnerable undoubled undertricks cost 50 · case 01
Vulnerable declarers lose half the penalty.
Vulnerable undoubled undertricks cost 50 · case 02
Vulnerable declarers lose half the penalty.
Vulnerable undoubled undertricks cost 50 · case 03
Vulnerable declarers lose half the penalty.
Vulnerable undoubled undertricks cost 50 · case 04
Vulnerable declarers lose half the penalty.
Vulnerable undoubled undertricks cost 50 · case 05
Vulnerable declarers lose half the penalty.
A player may double partner bid · case 01
Doubling your own side contract is accepted.
A player may double partner bid · case 02
Doubling your own side contract is accepted.
A player may double partner bid · case 03
Doubling your own side contract is accepted.
A player may double partner bid · case 04
Doubling your own side contract is accepted.
A player may double partner bid · case 05
Doubling your own side contract is accepted.
Passes before a double still count toward the end of the auction · case 01
An auction ends one pass after a balancing double.
Passes before a double still count toward the end of the auction · case 02
An auction ends one pass after a balancing double.
Passes before a double still count toward the end of the auction · case 03
An auction ends one pass after a balancing double.
Passes before a double still count toward the end of the auction · case 04
An auction ends one pass after a balancing double.
Passes before a double still count toward the end of the auction · case 05
An auction ends one pass after a balancing double.
A new bid keeps the previous double · case 01
The final contract reports X although a later bid overcalled the doubled contract.
A new bid keeps the previous double · case 02
The final contract reports X although a later bid overcalled the doubled contract.
A new bid keeps the previous double · case 03
The final contract reports X although a later bid overcalled the doubled contract.
A new bid keeps the previous double · case 04
The final contract reports X although a later bid overcalled the doubled contract.
A new bid keeps the previous double · case 05
The final contract reports X although a later bid overcalled the doubled contract.
The last bidder becomes declarer · case 01
When partner first named the strain, the raiser is reported as declarer.
The last bidder becomes declarer · case 02
When partner first named the strain, the raiser is reported as declarer.
The last bidder becomes declarer · case 03
When partner first named the strain, the raiser is reported as declarer.
The last bidder becomes declarer · case 04
When partner first named the strain, the raiser is reported as declarer.
The last bidder becomes declarer · case 05
When partner first named the strain, the raiser is reported as declarer.
A same-level lower strain bid is accepted · case 01
1H over 1S is accepted as sufficient.
A same-level lower strain bid is accepted · case 02
1H over 1S is accepted as sufficient.
A same-level lower strain bid is accepted · case 03
1H over 1S is accepted as sufficient.
A same-level lower strain bid is accepted · case 04
1H over 1S is accepted as sufficient.
A same-level lower strain bid is accepted · case 05
1H over 1S is accepted as sufficient.
The left bower keeps its printed suit · case 01
The jack of the same colour loses to small trumps and follows its printed suit.
The left bower keeps its printed suit · case 02
The jack of the same colour loses to small trumps and follows its printed suit.
The left bower keeps its printed suit · case 03
The jack of the same colour loses to small trumps and follows its printed suit.
The left bower keeps its printed suit · case 04
The jack of the same colour loses to small trumps and follows its printed suit.
The left bower keeps its printed suit · case 05
The jack of the same colour loses to small trumps and follows its printed suit.
Left bower outranks right bower · case 01
The same-colour jack beats the jack of trump.
Left bower outranks right bower · case 02
The same-colour jack beats the jack of trump.
Left bower outranks right bower · case 03
The same-colour jack beats the jack of trump.
Left bower outranks right bower · case 04
The same-colour jack beats the jack of trump.
Left bower outranks right bower · case 05
The same-colour jack beats the jack of trump.
The left bower cannot trump in · case 01
Playing the left bower on a led plain suit loses the trick.
The left bower cannot trump in · case 02
Playing the left bower on a led plain suit loses the trick.
The left bower cannot trump in · case 03
Playing the left bower on a led plain suit loses the trick.
The left bower cannot trump in · case 04
Playing the left bower on a led plain suit loses the trick.
The left bower cannot trump in · case 05
Playing the left bower on a led plain suit loses the trick.
Four tricks are scored as a march · case 01
Makers with four tricks get 2 points.
Four tricks are scored as a march · case 02
Makers with four tricks get 2 points.
Four tricks are scored as a march · case 03
Makers with four tricks get 2 points.
Four tricks are scored as a march · case 04
Makers with four tricks get 2 points.
Four tricks are scored as a march · case 05
Makers with four tricks get 2 points.
A lone hand taking three or four tricks scores 2 · case 01
Partial lone hands are over-rewarded.
A lone hand taking three or four tricks scores 2 · case 02
Partial lone hands are over-rewarded.
A lone hand taking three or four tricks scores 2 · case 03
Partial lone hands are over-rewarded.
A lone hand taking three or four tricks scores 2 · case 04
Partial lone hands are over-rewarded.
A lone hand taking three or four tricks scores 2 · case 05
Partial lone hands are over-rewarded.
A lone defender euchre scores only 2 · case 01
Defending alone earns no bonus.
A lone defender euchre scores only 2 · case 02
Defending alone earns no bonus.
A lone defender euchre scores only 2 · case 03
Defending alone earns no bonus.
A lone defender euchre scores only 2 · case 04
Defending alone earns no bonus.
A lone defender euchre scores only 2 · case 05
Defending alone earns no bonus.
A banker natural does not stop the player from drawing · case 01
Player draws against a banker 8 or 9.
A banker natural does not stop the player from drawing · case 02
Player draws against a banker 8 or 9.
A banker natural does not stop the player from drawing · case 03
Player draws against a banker 8 or 9.
A banker natural does not stop the player from drawing · case 04
Player draws against a banker 8 or 9.
A banker natural does not stop the player from drawing · case 05
Player draws against a banker 8 or 9.
Banker 3 draws against a player third-card 8 · case 01
Banker takes a card it must refuse.
Banker 3 draws against a player third-card 8 · case 02
Banker takes a card it must refuse.
Banker 3 draws against a player third-card 8 · case 03
Banker takes a card it must refuse.
Banker 3 draws against a player third-card 8 · case 04
Banker takes a card it must refuse.
Banker 3 draws against a player third-card 8 · case 05
Banker takes a card it must refuse.
Banker draws on 6 when the player stood · case 01
Banker 6 takes a card after player stands on 6-7.
Banker draws on 6 when the player stood · case 02
Banker 6 takes a card after player stands on 6-7.
Banker draws on 6 when the player stood · case 03
Banker 6 takes a card after player stands on 6-7.
Banker draws on 6 when the player stood · case 04
Banker 6 takes a card after player stands on 6-7.
Banker draws on 6 when the player stood · case 05
Banker 6 takes a card after player stands on 6-7.
Banker decisions use the player new total instead of the third card · case 01
The tableau is consulted with the wrong number.
Banker decisions use the player new total instead of the third card · case 02
The tableau is consulted with the wrong number.
Banker decisions use the player new total instead of the third card · case 03
The tableau is consulted with the wrong number.
Banker decisions use the player new total instead of the third card · case 04
The tableau is consulted with the wrong number.
Banker decisions use the player new total instead of the third card · case 05
The tableau is consulted with the wrong number.
Player draws on 6 · case 01
Player takes a third card on 6.
Player draws on 6 · case 02
Player takes a third card on 6.
Player draws on 6 · case 03
Player takes a third card on 6.
Player draws on 6 · case 04
Player takes a third card on 6.
Player draws on 6 · case 05
Player takes a third card on 6.
Dealing starts with the dealer · case 01
The dealer receives the first batch.
Dealing starts with the dealer · case 02
The dealer receives the first batch.
Dealing starts with the dealer · case 03
The dealer receives the first batch.
Dealing starts with the dealer · case 04
The dealer receives the first batch.
Dealing starts with the dealer · case 05
The dealer receives the first batch.
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 ↗