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
An ISBN-13-shaped token admits an unrelated prefix · case 01
An ISBN-13-shaped token admits an unrelated prefix.
An ISBN-13-shaped token admits an unrelated prefix · case 02
An ISBN-13-shaped token admits an unrelated prefix.
An ISBN-13-shaped token admits an unrelated prefix · case 03
An ISBN-13-shaped token admits an unrelated prefix.
An ISBN-13-shaped token admits an unrelated prefix · case 04
An ISBN-13-shaped token admits an unrelated prefix.
An ISBN-13-shaped token admits an unrelated prefix · case 05
An ISBN-13-shaped token admits an unrelated prefix.
A network-order word uses host-style little endian · case 01
A network-order word uses host-style little endian.
A network-order word uses host-style little endian · case 02
A network-order word uses host-style little endian.
A network-order word uses host-style little endian · case 03
A network-order word uses host-style little endian.
A network-order word uses host-style little endian · case 04
A network-order word uses host-style little endian.
A network-order word uses host-style little endian · case 05
A network-order word uses host-style little endian.
A signed octet is interpreted as an unsigned magnitude · case 01
A signed octet is interpreted as an unsigned magnitude.
A signed octet is interpreted as an unsigned magnitude · case 02
A signed octet is interpreted as an unsigned magnitude.
A signed octet is interpreted as an unsigned magnitude · case 03
A signed octet is interpreted as an unsigned magnitude.
A signed octet is interpreted as an unsigned magnitude · case 04
A signed octet is interpreted as an unsigned magnitude.
A signed octet is interpreted as an unsigned magnitude · case 05
A signed octet is interpreted as an unsigned magnitude.
A sign-magnitude octet is decoded as two-complement · case 01
A sign-magnitude octet is decoded as two-complement.
A sign-magnitude octet is decoded as two-complement · case 02
A sign-magnitude octet is decoded as two-complement.
A sign-magnitude octet is decoded as two-complement · case 03
A sign-magnitude octet is decoded as two-complement.
A sign-magnitude octet is decoded as two-complement · case 04
A sign-magnitude octet is decoded as two-complement.
A sign-magnitude octet is decoded as two-complement · case 05
A sign-magnitude octet is decoded as two-complement.
Zigzag decoding loses odd-value signs · case 01
Zigzag decoding loses odd-value signs.
Zigzag decoding loses odd-value signs · case 02
Zigzag decoding loses odd-value signs.
Zigzag decoding loses odd-value signs · case 03
Zigzag decoding loses odd-value signs.
Zigzag decoding loses odd-value signs · case 04
Zigzag decoding loses odd-value signs.
Zigzag decoding loses odd-value signs · case 05
Zigzag decoding loses odd-value signs.
Packed decimal decodes as a binary integer · case 01
Packed decimal decodes as a binary integer.
Packed decimal decodes as a binary integer · case 02
Packed decimal decodes as a binary integer.
Packed decimal decodes as a binary integer · case 03
Packed decimal decodes as a binary integer.
Packed decimal decodes as a binary integer · case 04
Packed decimal decodes as a binary integer.
Packed decimal decodes as a binary integer · case 05
Packed decimal decodes as a binary integer.
A packed-decimal sign nybble becomes a digit · case 01
A packed-decimal sign nybble becomes a digit.
A packed-decimal sign nybble becomes a digit · case 02
A packed-decimal sign nybble becomes a digit.
A packed-decimal sign nybble becomes a digit · case 03
A packed-decimal sign nybble becomes a digit.
A packed-decimal sign nybble becomes a digit · case 04
A packed-decimal sign nybble becomes a digit.
A packed-decimal sign nybble becomes a digit · case 05
A packed-decimal sign nybble becomes a digit.
Testing a flag requires every bit to equal the mask · case 01
Testing a flag requires every bit to equal the mask.
Testing a flag requires every bit to equal the mask · case 02
Testing a flag requires every bit to equal the mask.
Testing a flag requires every bit to equal the mask · case 03
Testing a flag requires every bit to equal the mask.
Testing a flag requires every bit to equal the mask · case 04
Testing a flag requires every bit to equal the mask.
Testing a flag requires every bit to equal the mask · case 05
Testing a flag requires every bit to equal the mask.
A packed field includes adjacent flag bits · case 01
A packed field includes adjacent flag bits.
A packed field includes adjacent flag bits · case 02
A packed field includes adjacent flag bits.
A packed field includes adjacent flag bits · case 03
A packed field includes adjacent flag bits.
A packed field includes adjacent flag bits · case 04
A packed field includes adjacent flag bits.
A packed field includes adjacent flag bits · case 05
A packed field includes adjacent flag bits.
Unknown reserved flag bits are silently retained · case 01
Unknown reserved flag bits are silently retained.
Unknown reserved flag bits are silently retained · case 02
Unknown reserved flag bits are silently retained.
Unknown reserved flag bits are silently retained · case 03
Unknown reserved flag bits are silently retained.
Unknown reserved flag bits are silently retained · case 04
Unknown reserved flag bits are silently retained.
Unknown reserved flag bits are silently retained · case 05
Unknown reserved flag bits are silently retained.
Bit expansion emits least-significant bits first · case 01
Bit expansion emits least-significant bits first.
Bit expansion emits least-significant bits first · case 02
Bit expansion emits least-significant bits first.
Bit expansion emits least-significant bits first · case 03
Bit expansion emits least-significant bits first.
Bit expansion emits least-significant bits first · case 04
Bit expansion emits least-significant bits first.
Bit expansion emits least-significant bits first · case 05
Bit expansion emits least-significant bits first.
Varint continuation bits contribute to the value · case 01
Varint continuation bits contribute to the value.
Varint continuation bits contribute to the value · case 02
Varint continuation bits contribute to the value.
Varint continuation bits contribute to the value · case 03
Varint continuation bits contribute to the value.
Varint continuation bits contribute to the value · case 04
Varint continuation bits contribute to the value.
Varint continuation bits contribute to the value · case 05
Varint continuation bits contribute to the value.
A byte-count prefix is trusted without checking body size · case 01
A byte-count prefix is trusted without checking body size.
A byte-count prefix is trusted without checking body size · case 02
A byte-count prefix is trusted without checking body size.
A byte-count prefix is trusted without checking body size · case 03
A byte-count prefix is trusted without checking body size.
A byte-count prefix is trusted without checking body size · case 04
A byte-count prefix is trusted without checking body size.
A byte-count prefix is trusted without checking body size · case 05
A byte-count prefix is trusted without checking body size.
A terminated field consumes padding after the first zero · case 01
A terminated field consumes padding after the first zero.
A terminated field consumes padding after the first zero · case 02
A terminated field consumes padding after the first zero.
A terminated field consumes padding after the first zero · case 03
A terminated field consumes padding after the first zero.
A terminated field consumes padding after the first zero · case 04
A terminated field consumes padding after the first zero.
A terminated field consumes padding after the first zero · case 05
A terminated field consumes padding after the first zero.
Fixed text padding removal destroys embedded zero bytes · case 01
Fixed text padding removal destroys embedded zero bytes.
Fixed text padding removal destroys embedded zero bytes · case 02
Fixed text padding removal destroys embedded zero bytes.
Fixed text padding removal destroys embedded zero bytes · case 03
Fixed text padding removal destroys embedded zero bytes.
Fixed text padding removal destroys embedded zero bytes · case 04
Fixed text padding removal destroys embedded zero bytes.
Fixed text padding removal destroys embedded zero bytes · case 05
Fixed text padding removal destroys embedded zero bytes.
A Pascal string length exceeds its physical slot · case 01
A Pascal string length exceeds its physical slot.
A Pascal string length exceeds its physical slot · case 02
A Pascal string length exceeds its physical slot.
A Pascal string length exceeds its physical slot · case 03
A Pascal string length exceeds its physical slot.
A Pascal string length exceeds its physical slot · case 04
A Pascal string length exceeds its physical slot.
A Pascal string length exceeds its physical slot · case 05
A Pascal string length exceeds its physical slot.
A three-byte field is padded on the wrong side · case 01
A three-byte field is padded on the wrong side.
A three-byte field is padded on the wrong side · case 02
A three-byte field is padded on the wrong side.
A three-byte field is padded on the wrong side · case 03
A three-byte field is padded on the wrong side.
A three-byte field is padded on the wrong side · case 04
A three-byte field is padded on the wrong side.
A three-byte field is padded on the wrong side · case 05
A three-byte field is padded on the wrong side.
An odd trailing byte is silently dropped from a word array · case 01
An odd trailing byte is silently dropped from a word array.
An odd trailing byte is silently dropped from a word array · case 02
An odd trailing byte is silently dropped from a word array.
An odd trailing byte is silently dropped from a word array · case 03
An odd trailing byte is silently dropped from a word array.
An odd trailing byte is silently dropped from a word array · case 04
An odd trailing byte is silently dropped from a word array.
An odd trailing byte is silently dropped from a word array · case 05
An odd trailing byte is silently dropped from a word array.
Hex nybbles are swapped within each byte · case 01
Hex nybbles are swapped within each byte.
Hex nybbles are swapped within each byte · case 02
Hex nybbles are swapped within each byte.
Hex nybbles are swapped within each byte · case 03
Hex nybbles are swapped within each byte.
Hex nybbles are swapped within each byte · case 04
Hex nybbles are swapped within each byte.
Hex nybbles are swapped within each byte · case 05
Hex nybbles are swapped within each byte.
Bit packing puts padding before the data · case 01
Bit packing puts padding before the data.
Bit packing puts padding before the data · case 02
Bit packing puts padding before the data.
Bit packing puts padding before the data · case 03
Bit packing puts padding before the data.
Bit packing puts padding before the data · case 04
Bit packing puts padding before the data.
Bit packing puts padding before the data · case 05
Bit packing puts padding before the data.
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 ↗