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
Drop cap shaped paragraph: cap gutter · case 01
Text beside the drop cap touches the cap.
Drop cap shaped paragraph: cap gutter · case 02
Text beside the drop cap touches the cap.
Drop cap shaped paragraph: cap gutter · case 03
Text beside the drop cap touches the cap.
Drop cap shaped paragraph: cap gutter · case 04
Text beside the drop cap touches the cap.
Drop cap shaped paragraph: cap gutter · case 05
Text beside the drop cap touches the cap.
Drop cap shaped paragraph: indent with drop cap · case 01
Paragraphs with a drop cap are also indented.
Drop cap shaped paragraph: indent with drop cap · case 02
Paragraphs with a drop cap are also indented.
Drop cap shaped paragraph: indent with drop cap · case 03
Paragraphs with a drop cap are also indented.
Drop cap shaped paragraph: indent with drop cap · case 04
Paragraphs with a drop cap are also indented.
Drop cap shaped paragraph: indent with drop cap · case 05
Paragraphs with a drop cap are also indented.
Drop cap shaped paragraph: initial letter consumption · case 01
The first line measures the initial letter twice.
Drop cap shaped paragraph: initial letter consumption · case 02
The first line measures the initial letter twice.
Drop cap shaped paragraph: initial letter consumption · case 03
The first line measures the initial letter twice.
Drop cap shaped paragraph: initial letter consumption · case 04
The first line measures the initial letter twice.
Drop cap shaped paragraph: initial letter consumption · case 05
The first line measures the initial letter twice.
Drop cap shaped paragraph: line fit boundary · case 01
Lines that exactly fill their shaped width are broken early.
Drop cap shaped paragraph: line fit boundary · case 02
Lines that exactly fill their shaped width are broken early.
Drop cap shaped paragraph: line fit boundary · case 03
Lines that exactly fill their shaped width are broken early.
Drop cap shaped paragraph: line fit boundary · case 04
Lines that exactly fill their shaped width are broken early.
Drop cap shaped paragraph: line fit boundary · case 05
Lines that exactly fill their shaped width are broken early.
Drop cap shaped paragraph: overwide word placement · case 01
Empty lines are emitted before words wider than the shaped measure.
Drop cap shaped paragraph: overwide word placement · case 02
Empty lines are emitted before words wider than the shaped measure.
Drop cap shaped paragraph: overwide word placement · case 03
Empty lines are emitted before words wider than the shaped measure.
Drop cap shaped paragraph: overwide word placement · case 04
Empty lines are emitted before words wider than the shaped measure.
Drop cap shaped paragraph: overwide word placement · case 05
Empty lines are emitted before words wider than the shaped measure.
Runt last-line prevention: runt length threshold · case 01
Last lines of exactly the minimum length are still rebalanced.
Runt last-line prevention: runt length threshold · case 02
Last lines of exactly the minimum length are still rebalanced.
Runt last-line prevention: runt length threshold · case 03
Last lines of exactly the minimum length are still rebalanced.
Runt last-line prevention: runt length threshold · case 04
Last lines of exactly the minimum length are still rebalanced.
Runt last-line prevention: runt length threshold · case 05
Last lines of exactly the minimum length are still rebalanced.
Runt last-line prevention: repeated rebalancing · case 01
A runt is only partly fixed when one moved word is not enough.
Runt last-line prevention: repeated rebalancing · case 02
A runt is only partly fixed when one moved word is not enough.
Runt last-line prevention: repeated rebalancing · case 03
A runt is only partly fixed when one moved word is not enough.
Runt last-line prevention: repeated rebalancing · case 04
A runt is only partly fixed when one moved word is not enough.
Runt last-line prevention: repeated rebalancing · case 05
A runt is only partly fixed when one moved word is not enough.
Runt last-line prevention: moved line fit · case 01
Rebalancing produces an overfull last line.
Runt last-line prevention: moved line fit · case 02
Rebalancing produces an overfull last line.
Runt last-line prevention: moved line fit · case 03
Rebalancing produces an overfull last line.
Runt last-line prevention: moved line fit · case 04
Rebalancing produces an overfull last line.
Runt last-line prevention: moved line fit · case 05
Rebalancing produces an overfull last line.
Runt last-line prevention: runt measure unit · case 01
Short last lines with several short words are left as runts.
Runt last-line prevention: runt measure unit · case 02
Short last lines with several short words are left as runts.
Runt last-line prevention: runt measure unit · case 03
Short last lines with several short words are left as runts.
Runt last-line prevention: runt measure unit · case 04
Short last lines with several short words are left as runts.
Runt last-line prevention: runt measure unit · case 05
Short last lines with several short words are left as runts.
Runt last-line prevention: greedy fill boundary · case 01
Words that exactly fill the measure are wrapped.
Runt last-line prevention: greedy fill boundary · case 02
Words that exactly fill the measure are wrapped.
Runt last-line prevention: greedy fill boundary · case 03
Words that exactly fill the measure are wrapped.
Runt last-line prevention: greedy fill boundary · case 04
Words that exactly fill the measure are wrapped.
Runt last-line prevention: greedy fill boundary · case 05
Words that exactly fill the measure are wrapped.
Runt last-line prevention: overwide word isolation · case 01
Overwide words are attached to the current line or leave empty lines.
Runt last-line prevention: overwide word isolation · case 02
Overwide words are attached to the current line or leave empty lines.
Runt last-line prevention: overwide word isolation · case 03
Overwide words are attached to the current line or leave empty lines.
Runt last-line prevention: overwide word isolation · case 04
Overwide words are attached to the current line or leave empty lines.
Runt last-line prevention: overwide word isolation · case 05
Overwide words are attached to the current line or leave empty lines.
Kerning and ligature line measure: kerning across spaces · case 01
Lines measure narrower when a word ends and the next begins with a kern pair.
Kerning and ligature line measure: kerning across spaces · case 02
Lines measure narrower when a word ends and the next begins with a kern pair.
Kerning and ligature line measure: kerning across spaces · case 03
Lines measure narrower when a word ends and the next begins with a kern pair.
Kerning and ligature line measure: kerning across spaces · case 04
Lines measure narrower when a word ends and the next begins with a kern pair.
Kerning and ligature line measure: kerning across spaces · case 05
Lines measure narrower when a word ends and the next begins with a kern pair.
Kerning and ligature line measure: kerning after ligature · case 01
Punctuation after a ligature is kerned against a hidden component glyph.
Kerning and ligature line measure: kerning after ligature · case 02
Punctuation after a ligature is kerned against a hidden component glyph.
Kerning and ligature line measure: kerning after ligature · case 03
Punctuation after a ligature is kerned against a hidden component glyph.
Kerning and ligature line measure: kerning after ligature · case 04
Punctuation after a ligature is kerned against a hidden component glyph.
Kerning and ligature line measure: kerning after ligature · case 05
Punctuation after a ligature is kerned against a hidden component glyph.
Kerning and ligature line measure: kern pair case sensitivity · case 01
Lowercase pairs receive the tighter uppercase kerning value.
Kerning and ligature line measure: kern pair case sensitivity · case 02
Lowercase pairs receive the tighter uppercase kerning value.
Kerning and ligature line measure: kern pair case sensitivity · case 03
Lowercase pairs receive the tighter uppercase kerning value.
Kerning and ligature line measure: kern pair case sensitivity · case 04
Lowercase pairs receive the tighter uppercase kerning value.
Kerning and ligature line measure: kern pair case sensitivity · case 05
Lowercase pairs receive the tighter uppercase kerning value.
Kerning and ligature line measure: interword space count · case 01
Every line measures one space too wide.
Kerning and ligature line measure: interword space count · case 02
Every line measures one space too wide.
Kerning and ligature line measure: interword space count · case 03
Every line measures one space too wide.
Kerning and ligature line measure: interword space count · case 04
Every line measures one space too wide.
Kerning and ligature line measure: interword space count · case 05
Every line measures one space too wide.
Kerning and ligature line measure: non-joiner handling · case 01
Compound words marked with a non-joiner still form ligatures.
Kerning and ligature line measure: non-joiner handling · case 02
Compound words marked with a non-joiner still form ligatures.
Kerning and ligature line measure: non-joiner handling · case 03
Compound words marked with a non-joiner still form ligatures.
Kerning and ligature line measure: non-joiner handling · case 04
Compound words marked with a non-joiner still form ligatures.
Kerning and ligature line measure: non-joiner handling · case 05
Compound words marked with a non-joiner still form ligatures.
Ties and discretionary hyphens: tie breakability · case 01
Lines break inside "Dr.~Knuth" style ties.
Ties and discretionary hyphens: tie breakability · case 02
Lines break inside "Dr.~Knuth" style ties.
Ties and discretionary hyphens: tie breakability · case 03
Lines break inside "Dr.~Knuth" style ties.
Ties and discretionary hyphens: tie breakability · case 04
Lines break inside "Dr.~Knuth" style ties.
Ties and discretionary hyphens: tie breakability · case 05
Lines break inside "Dr.~Knuth" style ties.
Ties and discretionary hyphens: unbroken discretionary rendering · case 01
Hyphens show inside words that were not broken.
Ties and discretionary hyphens: unbroken discretionary rendering · case 02
Hyphens show inside words that were not broken.
Ties and discretionary hyphens: unbroken discretionary rendering · case 03
Hyphens show inside words that were not broken.
Ties and discretionary hyphens: unbroken discretionary rendering · case 04
Hyphens show inside words that were not broken.
Ties and discretionary hyphens: unbroken discretionary rendering · case 05
Hyphens show inside words that were not broken.
Ties and discretionary hyphens: hyphen at taken discretionary · case 01
Words broken at a discretionary lose their hyphen.
Ties and discretionary hyphens: hyphen at taken discretionary · case 02
Words broken at a discretionary lose their hyphen.
Ties and discretionary hyphens: hyphen at taken discretionary · case 03
Words broken at a discretionary lose their hyphen.
Ties and discretionary hyphens: hyphen at taken discretionary · case 04
Words broken at a discretionary lose their hyphen.
Ties and discretionary hyphens: hyphen at taken discretionary · case 05
Words broken at a discretionary lose their hyphen.
Ties and discretionary hyphens: invisible break rendering · case 01
Zero-width break opportunities show up as spaces.
Ties and discretionary hyphens: invisible break rendering · case 02
Zero-width break opportunities show up as spaces.
Ties and discretionary hyphens: invisible break rendering · case 03
Zero-width break opportunities show up as spaces.
Ties and discretionary hyphens: invisible break rendering · case 04
Zero-width break opportunities show up as spaces.
Ties and discretionary hyphens: invisible break rendering · case 05
Zero-width break opportunities show up as spaces.
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 ↗