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
Discounted fare rounded half-to-even · case 01
A child fare of 75.075 is quoted as 75.07 instead of 75.08.
Discounted fare rounded half-to-even · case 02
A child fare of 75.075 is quoted as 75.07 instead of 75.08.
Discounted fare rounded half-to-even · case 03
A child fare of 75.075 is quoted as 75.07 instead of 75.08.
Discounted fare rounded half-to-even · case 04
A child fare of 75.075 is quoted as 75.07 instead of 75.08.
Discounted fare rounded half-to-even · case 05
A child fare of 75.075 is quoted as 75.07 instead of 75.08.
Routing exactly on a band limit pushed to the next band · case 01
A routing exactly 5% over MPM is charged a 10M surcharge.
Routing exactly on a band limit pushed to the next band · case 02
A routing exactly 5% over MPM is charged a 10M surcharge.
Routing exactly on a band limit pushed to the next band · case 03
A routing exactly 5% over MPM is charged a 10M surcharge.
Routing exactly on a band limit pushed to the next band · case 04
A routing exactly 5% over MPM is charged a 10M surcharge.
Routing exactly on a band limit pushed to the next band · case 05
A routing exactly 5% over MPM is charged a 10M surcharge.
Mileage ratio rounded before band selection · case 01
A routing 5.1% over MPM is charged only the 5M surcharge.
Mileage ratio rounded before band selection · case 02
A routing 5.1% over MPM is charged only the 5M surcharge.
Mileage ratio rounded before band selection · case 03
A routing 5.1% over MPM is charged only the 5M surcharge.
Mileage ratio rounded before band selection · case 04
A routing 5.1% over MPM is charged only the 5M surcharge.
Mileage ratio rounded before band selection · case 05
A routing 5.1% over MPM is charged only the 5M surcharge.
Ticketed point deduction added to mileage · case 01
Routings entitled to a mileage deduction are surcharged more heavily.
Ticketed point deduction added to mileage · case 02
Routings entitled to a mileage deduction are surcharged more heavily.
Ticketed point deduction added to mileage · case 03
Routings entitled to a mileage deduction are surcharged more heavily.
Ticketed point deduction added to mileage · case 04
Routings entitled to a mileage deduction are surcharged more heavily.
Ticketed point deduction added to mileage · case 05
Routings entitled to a mileage deduction are surcharged more heavily.
Routings beyond 25% priced at the top band · case 01
A routing 40% over MPM is sold with a 25M surcharge instead of being rejected.
Routings beyond 25% priced at the top band · case 02
A routing 40% over MPM is sold with a 25M surcharge instead of being rejected.
Routings beyond 25% priced at the top band · case 03
A routing 40% over MPM is sold with a 25M surcharge instead of being rejected.
Routings beyond 25% priced at the top band · case 04
A routing 40% over MPM is sold with a 25M surcharge instead of being rejected.
Routings beyond 25% priced at the top band · case 05
A routing 40% over MPM is sold with a 25M surcharge instead of being rejected.
Five percent mileage band skipped · case 01
Routings 1-5% over MPM are charged a 10M surcharge.
Five percent mileage band skipped · case 02
Routings 1-5% over MPM are charged a 10M surcharge.
Five percent mileage band skipped · case 03
Routings 1-5% over MPM are charged a 10M surcharge.
Five percent mileage band skipped · case 04
Routings 1-5% over MPM are charged a 10M surcharge.
Five percent mileage band skipped · case 05
Routings 1-5% over MPM are charged a 10M surcharge.
Round trips never priced as two one-way fares · case 01
A round trip is quoted with an expensive RT fare although two cheap one-way fares are open.
Round trips never priced as two one-way fares · case 02
A round trip is quoted with an expensive RT fare although two cheap one-way fares are open.
Round trips never priced as two one-way fares · case 03
A round trip is quoted with an expensive RT fare although two cheap one-way fares are open.
Round trips never priced as two one-way fares · case 04
A round trip is quoted with an expensive RT fare although two cheap one-way fares are open.
Round trips never priced as two one-way fares · case 05
A round trip is quoted with an expensive RT fare although two cheap one-way fares are open.
Fare with AP exactly met excluded · case 01
A 7-day advance purchase fare is not offered to a customer booking exactly seven days ahead.
Fare with AP exactly met excluded · case 02
A 7-day advance purchase fare is not offered to a customer booking exactly seven days ahead.
Fare with AP exactly met excluded · case 03
A 7-day advance purchase fare is not offered to a customer booking exactly seven days ahead.
Fare with AP exactly met excluded · case 04
A 7-day advance purchase fare is not offered to a customer booking exactly seven days ahead.
Fare with AP exactly met excluded · case 05
A 7-day advance purchase fare is not offered to a customer booking exactly seven days ahead.
Closed booking classes still priced · case 01
The lowest quote uses a class with no seats left.
Closed booking classes still priced · case 02
The lowest quote uses a class with no seats left.
Closed booking classes still priced · case 03
The lowest quote uses a class with no seats left.
Closed booking classes still priced · case 04
The lowest quote uses a class with no seats left.
Closed booking classes still priced · case 05
The lowest quote uses a class with no seats left.
Equal-price fares tie-broken by filing order · case 01
Two fares with the same price produce the one filed first rather than the higher class.
Equal-price fares tie-broken by filing order · case 02
Two fares with the same price produce the one filed first rather than the higher class.
Equal-price fares tie-broken by filing order · case 03
Two fares with the same price produce the one filed first rather than the higher class.
Equal-price fares tie-broken by filing order · case 04
Two fares with the same price produce the one filed first rather than the higher class.
Equal-price fares tie-broken by filing order · case 05
Two fares with the same price produce the one filed first rather than the higher class.
One-way trips priced at half a round-trip fare · case 01
One-way quotes undercut every published one-way fare.
One-way trips priced at half a round-trip fare · case 02
One-way quotes undercut every published one-way fare.
One-way trips priced at half a round-trip fare · case 03
One-way quotes undercut every published one-way fare.
One-way trips priced at half a round-trip fare · case 04
One-way quotes undercut every published one-way fare.
One-way trips priced at half a round-trip fare · case 05
One-way quotes undercut every published one-way fare.
NUC total rounded instead of truncated · case 01
The NUC total on the fare calculation line is a cent higher than the component sum allows.
NUC total rounded instead of truncated · case 02
The NUC total on the fare calculation line is a cent higher than the component sum allows.
NUC total rounded instead of truncated · case 03
The NUC total on the fare calculation line is a cent higher than the component sum allows.
NUC total rounded instead of truncated · case 04
The NUC total on the fare calculation line is a cent higher than the component sum allows.
NUC total rounded instead of truncated · case 05
The NUC total on the fare calculation line is a cent higher than the component sum allows.
Local fare rounded to nearest unit · case 01
Local fares are sometimes below the converted NUC amount.
Local fare rounded to nearest unit · case 02
Local fares are sometimes below the converted NUC amount.
Local fare rounded to nearest unit · case 03
Local fares are sometimes below the converted NUC amount.
Local fare rounded to nearest unit · case 04
Local fares are sometimes below the converted NUC amount.
Local fare rounded to nearest unit · case 05
Local fares are sometimes below the converted NUC amount.
Components truncated before summing · case 01
Multi-component journeys lose fractions of a cent per component and the total drops a cent.
Components truncated before summing · case 02
Multi-component journeys lose fractions of a cent per component and the total drops a cent.
Components truncated before summing · case 03
Multi-component journeys lose fractions of a cent per component and the total drops a cent.
Components truncated before summing · case 04
Multi-component journeys lose fractions of a cent per component and the total drops a cent.
Components truncated before summing · case 05
Multi-component journeys lose fractions of a cent per component and the total drops a cent.
NUC divided by the rate of exchange · case 01
JPY fares come out at a fraction of the correct amount.
NUC divided by the rate of exchange · case 02
JPY fares come out at a fraction of the correct amount.
NUC divided by the rate of exchange · case 03
JPY fares come out at a fraction of the correct amount.
NUC divided by the rate of exchange · case 04
JPY fares come out at a fraction of the correct amount.
NUC divided by the rate of exchange · case 05
JPY fares come out at a fraction of the correct amount.
Unit ceiling computed in binary floating point · case 01
A 100.00 NUC fare at ROE 1.1 is collected as 111 instead of 110.
Unit ceiling computed in binary floating point · case 02
A 100.00 NUC fare at ROE 1.1 is collected as 111 instead of 110.
Unit ceiling computed in binary floating point · case 03
A 100.00 NUC fare at ROE 1.1 is collected as 111 instead of 110.
Unit ceiling computed in binary floating point · case 04
A 100.00 NUC fare at ROE 1.1 is collected as 111 instead of 110.
Unit ceiling computed in binary floating point · case 05
A 100.00 NUC fare at ROE 1.1 is collected as 111 instead of 110.
Percentage fare tax charged on every departure · case 01
A US-originating round trip with a Mexican stop pays both US and Mexican percentage taxes.
Percentage fare tax charged on every departure · case 02
A US-originating round trip with a Mexican stop pays both US and Mexican percentage taxes.
Percentage fare tax charged on every departure · case 03
A US-originating round trip with a Mexican stop pays both US and Mexican percentage taxes.
Percentage fare tax charged on every departure · case 04
A US-originating round trip with a Mexican stop pays both US and Mexican percentage taxes.
Percentage fare tax charged on every departure · case 05
A US-originating round trip with a Mexican stop pays both US and Mexican percentage taxes.
Percentage tax levied on carrier surcharges · case 01
Adding YQ increases the percentage tax.
Percentage tax levied on carrier surcharges · case 02
Adding YQ increases the percentage tax.
Percentage tax levied on carrier surcharges · case 03
Adding YQ increases the percentage tax.
Percentage tax levied on carrier surcharges · case 04
Adding YQ increases the percentage tax.
Percentage tax levied on carrier surcharges · case 05
Adding YQ increases the percentage tax.
Departure tax keyed on the arrival country · case 01
A flight into London is charged the UK departure tax, and the flight out is not.
Departure tax keyed on the arrival country · case 02
A flight into London is charged the UK departure tax, and the flight out is not.
Departure tax keyed on the arrival country · case 03
A flight into London is charged the UK departure tax, and the flight out is not.
Departure tax keyed on the arrival country · case 04
A flight into London is charged the UK departure tax, and the flight out is not.
Departure tax keyed on the arrival country · case 05
A flight into London is charged the UK departure tax, and the flight out is not.
Origin taken from the final segment · case 01
Percentage tax follows the last departure rather than where the journey began.
Origin taken from the final segment · case 02
Percentage tax follows the last departure rather than where the journey began.
Origin taken from the final segment · case 03
Percentage tax follows the last departure rather than where the journey began.
Origin taken from the final segment · case 04
Percentage tax follows the last departure rather than where the journey began.
Origin taken from the final segment · case 05
Percentage tax follows the last departure rather than where the journey began.
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 ↗