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
Check constraint validation: Requires a value to be negative and NULL simultaneously · case 01
The query violates its result contract: requires a value to be negative and null simultaneously.
Check constraint validation: Requires a value to be negative and NULL simultaneously · case 02
The query violates its result contract: requires a value to be negative and null simultaneously.
Check constraint validation: Requires a value to be negative and NULL simultaneously · case 03
The query violates its result contract: requires a value to be negative and null simultaneously.
Check constraint validation: Requires a value to be negative and NULL simultaneously · case 04
The query violates its result contract: requires a value to be negative and null simultaneously.
Check constraint validation: Requires a value to be negative and NULL simultaneously · case 05
The query violates its result contract: requires a value to be negative and null simultaneously.
Migration join backfill: Backfills each row with the entire reference-table total · case 01
The query violates its result contract: backfills each row with the entire reference-table total.
Migration join backfill: Backfills each row with the entire reference-table total · case 02
The query violates its result contract: backfills each row with the entire reference-table total.
Migration join backfill: Backfills each row with the entire reference-table total · case 03
The query violates its result contract: backfills each row with the entire reference-table total.
Migration join backfill: Backfills each row with the entire reference-table total · case 04
The query violates its result contract: backfills each row with the entire reference-table total.
Migration join backfill: Backfills each row with the entire reference-table total · case 05
The query violates its result contract: backfills each row with the entire reference-table total.
Migration join backfill: Deduplicates equal reference contributions during backfill · case 01
The query violates its result contract: deduplicates equal reference contributions during backfill.
Migration join backfill: Deduplicates equal reference contributions during backfill · case 02
The query violates its result contract: deduplicates equal reference contributions during backfill.
Migration join backfill: Deduplicates equal reference contributions during backfill · case 03
The query violates its result contract: deduplicates equal reference contributions during backfill.
Migration join backfill: Deduplicates equal reference contributions during backfill · case 04
The query violates its result contract: deduplicates equal reference contributions during backfill.
Migration join backfill: Deduplicates equal reference contributions during backfill · case 05
The query violates its result contract: deduplicates equal reference contributions during backfill.
Migration join backfill: Invents zero for unmatched or unknown-only references · case 01
The query violates its result contract: invents zero for unmatched or unknown-only references.
Migration join backfill: Invents zero for unmatched or unknown-only references · case 02
The query violates its result contract: invents zero for unmatched or unknown-only references.
Migration join backfill: Invents zero for unmatched or unknown-only references · case 03
The query violates its result contract: invents zero for unmatched or unknown-only references.
Migration join backfill: Invents zero for unmatched or unknown-only references · case 04
The query violates its result contract: invents zero for unmatched or unknown-only references.
Migration join backfill: Invents zero for unmatched or unknown-only references · case 05
The query violates its result contract: invents zero for unmatched or unknown-only references.
Migration join backfill: Loses source records with no reference match · case 01
The query violates its result contract: loses source records with no reference match.
Migration join backfill: Loses source records with no reference match · case 02
The query violates its result contract: loses source records with no reference match.
Migration join backfill: Loses source records with no reference match · case 03
The query violates its result contract: loses source records with no reference match.
Migration join backfill: Loses source records with no reference match · case 04
The query violates its result contract: loses source records with no reference match.
Migration join backfill: Loses source records with no reference match · case 05
The query violates its result contract: loses source records with no reference match.
Migration join backfill: Matches NULL keys despite the ordinary equality contract · case 01
The query violates its result contract: matches null keys despite the ordinary equality contract.
Migration join backfill: Matches NULL keys despite the ordinary equality contract · case 02
The query violates its result contract: matches null keys despite the ordinary equality contract.
Migration join backfill: Matches NULL keys despite the ordinary equality contract · case 03
The query violates its result contract: matches null keys despite the ordinary equality contract.
Migration join backfill: Matches NULL keys despite the ordinary equality contract · case 04
The query violates its result contract: matches null keys despite the ordinary equality contract.
Migration join backfill: Matches NULL keys despite the ordinary equality contract · case 05
The query violates its result contract: matches null keys despite the ordinary equality contract.
Canonical combining marks remain out of order · case 01
Canonical combining marks remain out of order.
Canonical combining marks remain out of order · case 02
Canonical combining marks remain out of order.
Canonical combining marks remain out of order · case 03
Canonical combining marks remain out of order.
Canonical combining marks remain out of order · case 04
Canonical combining marks remain out of order.
Canonical combining marks remain out of order · case 05
Canonical combining marks remain out of order.
Compatibility ligatures survive a search key · case 01
Compatibility ligatures survive a search key.
Compatibility ligatures survive a search key · case 02
Compatibility ligatures survive a search key.
Compatibility ligatures survive a search key · case 03
Compatibility ligatures survive a search key.
Compatibility ligatures survive a search key · case 04
Compatibility ligatures survive a search key.
Compatibility ligatures survive a search key · case 05
Compatibility ligatures survive a search key.
Hangul syllables bypass canonical decomposition · case 01
Hangul syllables bypass canonical decomposition.
Hangul syllables bypass canonical decomposition · case 02
Hangul syllables bypass canonical decomposition.
Hangul syllables bypass canonical decomposition · case 03
Hangul syllables bypass canonical decomposition.
Hangul syllables bypass canonical decomposition · case 04
Hangul syllables bypass canonical decomposition.
Hangul syllables bypass canonical decomposition · case 05
Hangul syllables bypass canonical decomposition.
A compatibility fraction remains opaque · case 01
A compatibility fraction remains opaque.
A compatibility fraction remains opaque · case 02
A compatibility fraction remains opaque.
A compatibility fraction remains opaque · case 03
A compatibility fraction remains opaque.
A compatibility fraction remains opaque · case 04
A compatibility fraction remains opaque.
A compatibility fraction remains opaque · case 05
A compatibility fraction remains opaque.
Lowercasing misses multi-character caseless matches · case 01
Lowercasing misses multi-character caseless matches.
Lowercasing misses multi-character caseless matches · case 02
Lowercasing misses multi-character caseless matches.
Lowercasing misses multi-character caseless matches · case 03
Lowercasing misses multi-character caseless matches.
Lowercasing misses multi-character caseless matches · case 04
Lowercasing misses multi-character caseless matches.
Lowercasing misses multi-character caseless matches · case 05
Lowercasing misses multi-character caseless matches.
Case folding leaves a decomposed identity · case 01
Case folding leaves a decomposed identity.
Case folding leaves a decomposed identity · case 02
Case folding leaves a decomposed identity.
Case folding leaves a decomposed identity · case 03
Case folding leaves a decomposed identity.
Case folding leaves a decomposed identity · case 04
Case folding leaves a decomposed identity.
Case folding leaves a decomposed identity · case 05
Case folding leaves a decomposed identity.
Accent removal drops non-Latin letters · case 01
Accent removal drops non-Latin letters.
Accent removal drops non-Latin letters · case 02
Accent removal drops non-Latin letters.
Accent removal drops non-Latin letters · case 03
Accent removal drops non-Latin letters.
Accent removal drops non-Latin letters · case 04
Accent removal drops non-Latin letters.
Accent removal drops non-Latin letters · case 05
Accent removal drops non-Latin letters.
A superscript is accepted as a decimal digit · case 01
A superscript is accepted as a decimal digit.
A superscript is accepted as a decimal digit · case 02
A superscript is accepted as a decimal digit.
A superscript is accepted as a decimal digit · case 03
A superscript is accepted as a decimal digit.
A superscript is accepted as a decimal digit · case 04
A superscript is accepted as a decimal digit.
A superscript is accepted as a decimal digit · case 05
A superscript is accepted as a decimal digit.
Non-decimal numeric characters are rejected · case 01
Non-decimal numeric characters are rejected.
Non-decimal numeric characters are rejected · case 02
Non-decimal numeric characters are rejected.
Non-decimal numeric characters are rejected · case 03
Non-decimal numeric characters are rejected.
Non-decimal numeric characters are rejected · case 04
Non-decimal numeric characters are rejected.
Non-decimal numeric characters are rejected · case 05
Non-decimal numeric characters are rejected.
Unicode digits leak into an ASCII decimal token · case 01
Unicode digits leak into an ASCII decimal token.
Unicode digits leak into an ASCII decimal token · case 02
Unicode digits leak into an ASCII decimal token.
Unicode digits leak into an ASCII decimal token · case 03
Unicode digits leak into an ASCII decimal token.
Unicode digits leak into an ASCII decimal token · case 04
Unicode digits leak into an ASCII decimal token.
Unicode digits leak into an ASCII decimal token · case 05
Unicode digits leak into an ASCII decimal token.
An identifier rejects underscores and admits leading digits · case 01
An identifier rejects underscores and admits leading digits.
An identifier rejects underscores and admits leading digits · case 02
An identifier rejects underscores and admits leading digits.
An identifier rejects underscores and admits leading digits · case 03
An identifier rejects underscores and admits leading digits.
An identifier rejects underscores and admits leading digits · case 04
An identifier rejects underscores and admits leading digits.
An identifier rejects underscores and admits leading digits · case 05
An identifier rejects underscores and admits leading digits.
A line separator is treated as printable text · case 01
A line separator is treated as printable text.
A line separator is treated as printable text · case 02
A line separator is treated as printable text.
A line separator is treated as printable text · case 03
A line separator is treated as printable text.
A line separator is treated as printable text · case 04
A line separator is treated as printable text.
A line separator is treated as printable text · case 05
A line separator is treated as printable text.
A nonbreaking space is not recognized as whitespace · case 01
A nonbreaking space is not recognized as whitespace.
A nonbreaking space is not recognized as whitespace · case 02
A nonbreaking space is not recognized as whitespace.
A nonbreaking space is not recognized as whitespace · case 03
A nonbreaking space is not recognized as whitespace.
A nonbreaking space is not recognized as whitespace · case 04
A nonbreaking space is not recognized as whitespace.
A nonbreaking space is not recognized as whitespace · case 05
A nonbreaking space is not recognized as whitespace.
Uncased punctuation invalidates uppercase text · case 01
Uncased punctuation invalidates uppercase text.
Uncased punctuation invalidates uppercase text · case 02
Uncased punctuation invalidates uppercase text.
Uncased punctuation invalidates uppercase text · case 03
Uncased punctuation invalidates uppercase text.
Uncased punctuation invalidates uppercase text · case 04
Uncased punctuation invalidates uppercase text.
Uncased punctuation invalidates uppercase text · case 05
Uncased punctuation invalidates uppercase text.
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 ↗