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
Replacement counting reports matches instead of actual replacements · case 01
Replacement counting reports matches instead of actual replacements.
Replacement counting reports matches instead of actual replacements · case 02
Replacement counting reports matches instead of actual replacements.
Replacement counting reports matches instead of actual replacements · case 03
Replacement counting reports matches instead of actual replacements.
Replacement counting reports matches instead of actual replacements · case 04
Replacement counting reports matches instead of actual replacements.
Replacement counting reports matches instead of actual replacements · case 05
Replacement counting reports matches instead of actual replacements.
Repeated token validation compares shape rather than content · case 01
Repeated token validation compares shape rather than content.
Repeated token validation compares shape rather than content · case 02
Repeated token validation compares shape rather than content.
Repeated token validation compares shape rather than content · case 03
Repeated token validation compares shape rather than content.
Repeated token validation compares shape rather than content · case 04
Repeated token validation compares shape rather than content.
Repeated token validation compares shape rather than content · case 05
Repeated token validation compares shape rather than content.
A choice validator anchors only one alternative · case 01
A choice validator anchors only one alternative.
A choice validator anchors only one alternative · case 02
A choice validator anchors only one alternative.
A choice validator anchors only one alternative · case 03
A choice validator anchors only one alternative.
A choice validator anchors only one alternative · case 04
A choice validator anchors only one alternative.
A choice validator anchors only one alternative · case 05
A choice validator anchors only one alternative.
A minimal token matcher yields empty tokens between characters · case 01
A minimal token matcher yields empty tokens between characters.
A minimal token matcher yields empty tokens between characters · case 02
A minimal token matcher yields empty tokens between characters.
A minimal token matcher yields empty tokens between characters · case 03
A minimal token matcher yields empty tokens between characters.
A minimal token matcher yields empty tokens between characters · case 04
A minimal token matcher yields empty tokens between characters.
A minimal token matcher yields empty tokens between characters · case 05
A minimal token matcher yields empty tokens between characters.
A byte-budget truncation returns a partial UTF-8 scalar · case 01
A byte-budget truncation returns a partial UTF-8 scalar.
A byte-budget truncation returns a partial UTF-8 scalar · case 02
A byte-budget truncation returns a partial UTF-8 scalar.
A byte-budget truncation returns a partial UTF-8 scalar · case 03
A byte-budget truncation returns a partial UTF-8 scalar.
A byte-budget truncation returns a partial UTF-8 scalar · case 04
A byte-budget truncation returns a partial UTF-8 scalar.
A byte-budget truncation returns a partial UTF-8 scalar · case 05
A byte-budget truncation returns a partial UTF-8 scalar.
UTF-16 code units are interpreted as Unicode scalars · case 01
UTF-16 code units are interpreted as Unicode scalars.
UTF-16 code units are interpreted as Unicode scalars · case 02
UTF-16 code units are interpreted as Unicode scalars.
UTF-16 code units are interpreted as Unicode scalars · case 03
UTF-16 code units are interpreted as Unicode scalars.
UTF-16 code units are interpreted as Unicode scalars · case 04
UTF-16 code units are interpreted as Unicode scalars.
UTF-16 code units are interpreted as Unicode scalars · case 05
UTF-16 code units are interpreted as Unicode scalars.
An optional BOM is appended instead of prepended · case 01
An optional BOM is appended instead of prepended.
An optional BOM is appended instead of prepended · case 02
An optional BOM is appended instead of prepended.
An optional BOM is appended instead of prepended · case 03
An optional BOM is appended instead of prepended.
An optional BOM is appended instead of prepended · case 04
An optional BOM is appended instead of prepended.
An optional BOM is appended instead of prepended · case 05
An optional BOM is appended instead of prepended.
A literal plus is not escaped in UTF-7 · case 01
A literal plus is not escaped in UTF-7.
A literal plus is not escaped in UTF-7 · case 02
A literal plus is not escaped in UTF-7.
A literal plus is not escaped in UTF-7 · case 03
A literal plus is not escaped in UTF-7.
A literal plus is not escaped in UTF-7 · case 04
A literal plus is not escaped in UTF-7.
A literal plus is not escaped in UTF-7 · case 05
A literal plus is not escaped in UTF-7.
Unicode escape encoding mistakes literal escape text for a character · case 01
Unicode escape encoding mistakes literal escape text for a character.
Unicode escape encoding mistakes literal escape text for a character · case 02
Unicode escape encoding mistakes literal escape text for a character.
Unicode escape encoding mistakes literal escape text for a character · case 03
Unicode escape encoding mistakes literal escape text for a character.
Unicode escape encoding mistakes literal escape text for a character · case 04
Unicode escape encoding mistakes literal escape text for a character.
Unicode escape encoding mistakes literal escape text for a character · case 05
Unicode escape encoding mistakes literal escape text for a character.
A common prefix routine chooses the shortest whole input · case 01
A common prefix routine chooses the shortest whole input.
A common prefix routine chooses the shortest whole input · case 02
A common prefix routine chooses the shortest whole input.
A common prefix routine chooses the shortest whole input · case 03
A common prefix routine chooses the shortest whole input.
A common prefix routine chooses the shortest whole input · case 04
A common prefix routine chooses the shortest whole input.
A common prefix routine chooses the shortest whole input · case 05
A common prefix routine chooses the shortest whole input.
A suffix comparison scans from the front · case 01
A suffix comparison scans from the front.
A suffix comparison scans from the front · case 02
A suffix comparison scans from the front.
A suffix comparison scans from the front · case 03
A suffix comparison scans from the front.
A suffix comparison scans from the front · case 04
A suffix comparison scans from the front.
A suffix comparison scans from the front · case 05
A suffix comparison scans from the front.
Cascaded substitutions rewrite newly inserted text · case 01
Cascaded substitutions rewrite newly inserted text.
Cascaded substitutions rewrite newly inserted text · case 02
Cascaded substitutions rewrite newly inserted text.
Cascaded substitutions rewrite newly inserted text · case 03
Cascaded substitutions rewrite newly inserted text.
Cascaded substitutions rewrite newly inserted text · case 04
Cascaded substitutions rewrite newly inserted text.
Cascaded substitutions rewrite newly inserted text · case 05
Cascaded substitutions rewrite newly inserted text.
A replacement repeats until newly created matches disappear · case 01
A replacement repeats until newly created matches disappear.
A replacement repeats until newly created matches disappear · case 02
A replacement repeats until newly created matches disappear.
A replacement repeats until newly created matches disappear · case 03
A replacement repeats until newly created matches disappear.
A replacement repeats until newly created matches disappear · case 04
A replacement repeats until newly created matches disappear.
A replacement repeats until newly created matches disappear · case 05
A replacement repeats until newly created matches disappear.
Character bigram extraction omits the last window · case 01
Character bigram extraction omits the last window.
Character bigram extraction omits the last window · case 02
Character bigram extraction omits the last window.
Character bigram extraction omits the last window · case 03
Character bigram extraction omits the last window.
Character bigram extraction omits the last window · case 04
Character bigram extraction omits the last window.
Character bigram extraction omits the last window · case 05
Character bigram extraction omits the last window.
Word bigrams cross a record boundary · case 01
Word bigrams cross a record boundary.
Word bigrams cross a record boundary · case 02
Word bigrams cross a record boundary.
Word bigrams cross a record boundary · case 03
Word bigrams cross a record boundary.
Word bigrams cross a record boundary · case 04
Word bigrams cross a record boundary.
Word bigrams cross a record boundary · case 05
Word bigrams cross a record boundary.
Stopword removal deletes a substring of another word · case 01
Stopword removal deletes a substring of another word.
Stopword removal deletes a substring of another word · case 02
Stopword removal deletes a substring of another word.
Stopword removal deletes a substring of another word · case 03
Stopword removal deletes a substring of another word.
Stopword removal deletes a substring of another word · case 04
Stopword removal deletes a substring of another word.
Stopword removal deletes a substring of another word · case 05
Stopword removal deletes a substring of another word.
Text edit distance counts only length difference · case 01
Text edit distance counts only length difference.
Text edit distance counts only length difference · case 02
Text edit distance counts only length difference.
Text edit distance counts only length difference · case 03
Text edit distance counts only length difference.
Text edit distance counts only length difference · case 04
Text edit distance counts only length difference.
Text edit distance counts only length difference · case 05
Text edit distance counts only length difference.
A trie prefix is reported as a complete word · case 01
A trie prefix is reported as a complete word.
A trie prefix is reported as a complete word · case 02
A trie prefix is reported as a complete word.
A trie prefix is reported as a complete word · case 03
A trie prefix is reported as a complete word.
A trie prefix is reported as a complete word · case 04
A trie prefix is reported as a complete word.
A trie prefix is reported as a complete word · case 05
A trie prefix is reported as a complete word.
Entity decoding keeps only the first resulting codepoint · case 01
Entity decoding keeps only the first resulting codepoint.
Entity decoding keeps only the first resulting codepoint · case 02
Entity decoding keeps only the first resulting codepoint.
Entity decoding keeps only the first resulting codepoint · case 03
Entity decoding keeps only the first resulting codepoint.
Entity decoding keeps only the first resulting codepoint · case 04
Entity decoding keeps only the first resulting codepoint.
Entity decoding keeps only the first resulting codepoint · case 05
Entity decoding keeps only the first resulting codepoint.
CDATA serialization emits an embedded terminator · case 01
CDATA serialization emits an embedded terminator.
CDATA serialization emits an embedded terminator · case 02
CDATA serialization emits an embedded terminator.
CDATA serialization emits an embedded terminator · case 03
CDATA serialization emits an embedded terminator.
CDATA serialization emits an embedded terminator · case 04
CDATA serialization emits an embedded terminator.
CDATA serialization emits an embedded terminator · case 05
CDATA serialization emits an embedded terminator.
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 ↗