FAILURE MAP

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 ↗
100840Executable case variants
20168Distinct failure mechanisms
302520Executed implementations
20168Open-access cases

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

Python · Standard library
REFERENCEFAILURE MECHANISMDOMAINACCESS
FA-28201

Apply redirect interception to the current hop before validating and dispatching the selected target: follow action only · case 01

Apply redirect interception to the current hop before validating and dispatching the selected target: the follow action only branch emits an incorrect decision.

HTTP redirects● Open access↗
FA-28202

Apply redirect interception to the current hop before validating and dispatching the selected target: follow action only · case 02

Apply redirect interception to the current hop before validating and dispatching the selected target: the follow action only branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28203

Apply redirect interception to the current hop before validating and dispatching the selected target: follow action only · case 03

Apply redirect interception to the current hop before validating and dispatching the selected target: the follow action only branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28204

Apply redirect interception to the current hop before validating and dispatching the selected target: follow action only · case 04

Apply redirect interception to the current hop before validating and dispatching the selected target: the follow action only branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28205

Apply redirect interception to the current hop before validating and dispatching the selected target: follow action only · case 05

Apply redirect interception to the current hop before validating and dispatching the selected target: the follow action only branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28206

Apply redirect interception to the current hop before validating and dispatching the selected target: callback current hop url · case 01

Apply redirect interception to the current hop before validating and dispatching the selected target: the callback current hop url branch emits an incorrect decision.

HTTP redirects● Open access↗
FA-28207

Apply redirect interception to the current hop before validating and dispatching the selected target: callback current hop url · case 02

Apply redirect interception to the current hop before validating and dispatching the selected target: the callback current hop url branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28208

Apply redirect interception to the current hop before validating and dispatching the selected target: callback current hop url · case 03

Apply redirect interception to the current hop before validating and dispatching the selected target: the callback current hop url branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28209

Apply redirect interception to the current hop before validating and dispatching the selected target: callback current hop url · case 04

Apply redirect interception to the current hop before validating and dispatching the selected target: the callback current hop url branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28210

Apply redirect interception to the current hop before validating and dispatching the selected target: callback current hop url · case 05

Apply redirect interception to the current hop before validating and dispatching the selected target: the callback current hop url branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28211

Apply redirect interception to the current hop before validating and dispatching the selected target: raw header occurrences · case 01

Apply redirect interception to the current hop before validating and dispatching the selected target: the raw header occurrences branch emits an incorrect decision.

HTTP redirects● Open access↗
FA-28212

Apply redirect interception to the current hop before validating and dispatching the selected target: raw header occurrences · case 02

Apply redirect interception to the current hop before validating and dispatching the selected target: the raw header occurrences branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28213

Apply redirect interception to the current hop before validating and dispatching the selected target: raw header occurrences · case 03

Apply redirect interception to the current hop before validating and dispatching the selected target: the raw header occurrences branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28214

Apply redirect interception to the current hop before validating and dispatching the selected target: raw header occurrences · case 04

Apply redirect interception to the current hop before validating and dispatching the selected target: the raw header occurrences branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28215

Apply redirect interception to the current hop before validating and dispatching the selected target: raw header occurrences · case 05

Apply redirect interception to the current hop before validating and dispatching the selected target: the raw header occurrences branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28216

Apply redirect interception to the current hop before validating and dispatching the selected target: synthetic stops network follow · case 01

Apply redirect interception to the current hop before validating and dispatching the selected target: the synthetic stops network follow branch emits an incorrect decision.

HTTP redirects● Open access↗
FA-28217

Apply redirect interception to the current hop before validating and dispatching the selected target: synthetic stops network follow · case 02

Apply redirect interception to the current hop before validating and dispatching the selected target: the synthetic stops network follow branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28218

Apply redirect interception to the current hop before validating and dispatching the selected target: synthetic stops network follow · case 03

Apply redirect interception to the current hop before validating and dispatching the selected target: the synthetic stops network follow branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28219

Apply redirect interception to the current hop before validating and dispatching the selected target: synthetic stops network follow · case 04

Apply redirect interception to the current hop before validating and dispatching the selected target: the synthetic stops network follow branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28220

Apply redirect interception to the current hop before validating and dispatching the selected target: synthetic stops network follow · case 05

Apply redirect interception to the current hop before validating and dispatching the selected target: the synthetic stops network follow branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28221

Apply redirect interception to the current hop before validating and dispatching the selected target: callback error fails chain · case 01

Apply redirect interception to the current hop before validating and dispatching the selected target: the callback error fails chain branch emits an incorrect decision.

HTTP redirects● Open access↗
FA-28222

Apply redirect interception to the current hop before validating and dispatching the selected target: callback error fails chain · case 02

Apply redirect interception to the current hop before validating and dispatching the selected target: the callback error fails chain branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28223

Apply redirect interception to the current hop before validating and dispatching the selected target: callback error fails chain · case 03

Apply redirect interception to the current hop before validating and dispatching the selected target: the callback error fails chain branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28224

Apply redirect interception to the current hop before validating and dispatching the selected target: callback error fails chain · case 04

Apply redirect interception to the current hop before validating and dispatching the selected target: the callback error fails chain branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28225

Apply redirect interception to the current hop before validating and dispatching the selected target: callback error fails chain · case 05

Apply redirect interception to the current hop before validating and dispatching the selected target: the callback error fails chain branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28226

Apply redirect interception to the current hop before validating and dispatching the selected target: cached hop still intercepted · case 01

Apply redirect interception to the current hop before validating and dispatching the selected target: the cached hop still intercepted branch emits an incorrect decision.

HTTP redirects● Open access↗
FA-28227

Apply redirect interception to the current hop before validating and dispatching the selected target: cached hop still intercepted · case 02

Apply redirect interception to the current hop before validating and dispatching the selected target: the cached hop still intercepted branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28228

Apply redirect interception to the current hop before validating and dispatching the selected target: cached hop still intercepted · case 03

Apply redirect interception to the current hop before validating and dispatching the selected target: the cached hop still intercepted branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28229

Apply redirect interception to the current hop before validating and dispatching the selected target: cached hop still intercepted · case 04

Apply redirect interception to the current hop before validating and dispatching the selected target: the cached hop still intercepted branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28230

Apply redirect interception to the current hop before validating and dispatching the selected target: cached hop still intercepted · case 05

Apply redirect interception to the current hop before validating and dispatching the selected target: the cached hop still intercepted branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28231

Apply redirect interception to the current hop before validating and dispatching the selected target: validate after target override · case 01

Apply redirect interception to the current hop before validating and dispatching the selected target: the validate after target override branch emits an incorrect decision.

HTTP redirects● Open access↗
FA-28232

Apply redirect interception to the current hop before validating and dispatching the selected target: validate after target override · case 02

Apply redirect interception to the current hop before validating and dispatching the selected target: the validate after target override branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28233

Apply redirect interception to the current hop before validating and dispatching the selected target: validate after target override · case 03

Apply redirect interception to the current hop before validating and dispatching the selected target: the validate after target override branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28234

Apply redirect interception to the current hop before validating and dispatching the selected target: validate after target override · case 04

Apply redirect interception to the current hop before validating and dispatching the selected target: the validate after target override branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28235

Apply redirect interception to the current hop before validating and dispatching the selected target: validate after target override · case 05

Apply redirect interception to the current hop before validating and dispatching the selected target: the validate after target override branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28236

Apply redirect interception to the current hop before validating and dispatching the selected target: synthetic status separate from hop · case 01

Apply redirect interception to the current hop before validating and dispatching the selected target: the synthetic status separate from hop branch emits an incorrect decision.

HTTP redirects● Open access↗
FA-28237

Apply redirect interception to the current hop before validating and dispatching the selected target: synthetic status separate from hop · case 02

Apply redirect interception to the current hop before validating and dispatching the selected target: the synthetic status separate from hop branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28238

Apply redirect interception to the current hop before validating and dispatching the selected target: synthetic status separate from hop · case 03

Apply redirect interception to the current hop before validating and dispatching the selected target: the synthetic status separate from hop branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28239

Apply redirect interception to the current hop before validating and dispatching the selected target: synthetic status separate from hop · case 04

Apply redirect interception to the current hop before validating and dispatching the selected target: the synthetic status separate from hop branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28240

Apply redirect interception to the current hop before validating and dispatching the selected target: synthetic status separate from hop · case 05

Apply redirect interception to the current hop before validating and dispatching the selected target: the synthetic status separate from hop branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28241

Build a bounded manual redirect result without issuing the next request: opaque location · case 01

Build a bounded manual redirect result without issuing the next request: the opaque location branch emits an incorrect decision.

HTTP redirects● Open access↗
FA-28242

Build a bounded manual redirect result without issuing the next request: opaque location · case 02

Build a bounded manual redirect result without issuing the next request: the opaque location branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28243

Build a bounded manual redirect result without issuing the next request: opaque location · case 03

Build a bounded manual redirect result without issuing the next request: the opaque location branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28244

Build a bounded manual redirect result without issuing the next request: opaque location · case 04

Build a bounded manual redirect result without issuing the next request: the opaque location branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28245

Build a bounded manual redirect result without issuing the next request: opaque location · case 05

Build a bounded manual redirect result without issuing the next request: the opaque location branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28246

Build a bounded manual redirect result without issuing the next request: manual no dispatch · case 01

Build a bounded manual redirect result without issuing the next request: the manual no dispatch branch emits an incorrect decision.

HTTP redirects● Open access↗
FA-28247

Build a bounded manual redirect result without issuing the next request: manual no dispatch · case 02

Build a bounded manual redirect result without issuing the next request: the manual no dispatch branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28248

Build a bounded manual redirect result without issuing the next request: manual no dispatch · case 03

Build a bounded manual redirect result without issuing the next request: the manual no dispatch branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28249

Build a bounded manual redirect result without issuing the next request: manual no dispatch · case 04

Build a bounded manual redirect result without issuing the next request: the manual no dispatch branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28250

Build a bounded manual redirect result without issuing the next request: manual no dispatch · case 05

Build a bounded manual redirect result without issuing the next request: the manual no dispatch branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28251

Build a bounded manual redirect result without issuing the next request: redirect error envelope · case 01

Build a bounded manual redirect result without issuing the next request: the redirect error envelope branch emits an incorrect decision.

HTTP redirects● Open access↗
FA-28252

Build a bounded manual redirect result without issuing the next request: redirect error envelope · case 02

Build a bounded manual redirect result without issuing the next request: the redirect error envelope branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28253

Build a bounded manual redirect result without issuing the next request: redirect error envelope · case 03

Build a bounded manual redirect result without issuing the next request: the redirect error envelope branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28254

Build a bounded manual redirect result without issuing the next request: redirect error envelope · case 04

Build a bounded manual redirect result without issuing the next request: the redirect error envelope branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28255

Build a bounded manual redirect result without issuing the next request: redirect error envelope · case 05

Build a bounded manual redirect result without issuing the next request: the redirect error envelope branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28256

Build a bounded manual redirect result without issuing the next request: opaque status · case 01

Build a bounded manual redirect result without issuing the next request: the opaque status branch emits an incorrect decision.

HTTP redirects● Open access↗
FA-28257

Build a bounded manual redirect result without issuing the next request: opaque status · case 02

Build a bounded manual redirect result without issuing the next request: the opaque status branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28258

Build a bounded manual redirect result without issuing the next request: opaque status · case 03

Build a bounded manual redirect result without issuing the next request: the opaque status branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28259

Build a bounded manual redirect result without issuing the next request: opaque status · case 04

Build a bounded manual redirect result without issuing the next request: the opaque status branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28260

Build a bounded manual redirect result without issuing the next request: opaque status · case 05

Build a bounded manual redirect result without issuing the next request: the opaque status branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28261

Build a bounded manual redirect result without issuing the next request: opaque body · case 01

Build a bounded manual redirect result without issuing the next request: the opaque body branch emits an incorrect decision.

HTTP redirects● Open access↗
FA-28262

Build a bounded manual redirect result without issuing the next request: opaque body · case 02

Build a bounded manual redirect result without issuing the next request: the opaque body branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28263

Build a bounded manual redirect result without issuing the next request: opaque body · case 03

Build a bounded manual redirect result without issuing the next request: the opaque body branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28264

Build a bounded manual redirect result without issuing the next request: opaque body · case 04

Build a bounded manual redirect result without issuing the next request: the opaque body branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28265

Build a bounded manual redirect result without issuing the next request: opaque body · case 05

Build a bounded manual redirect result without issuing the next request: the opaque body branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28266

Build a bounded manual redirect result without issuing the next request: manual result kind · case 01

Build a bounded manual redirect result without issuing the next request: the manual result kind branch emits an incorrect decision.

HTTP redirects● Open access↗
FA-28267

Build a bounded manual redirect result without issuing the next request: manual result kind · case 02

Build a bounded manual redirect result without issuing the next request: the manual result kind branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28268

Build a bounded manual redirect result without issuing the next request: manual result kind · case 03

Build a bounded manual redirect result without issuing the next request: the manual result kind branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28269

Build a bounded manual redirect result without issuing the next request: manual result kind · case 04

Build a bounded manual redirect result without issuing the next request: the manual result kind branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28270

Build a bounded manual redirect result without issuing the next request: manual result kind · case 05

Build a bounded manual redirect result without issuing the next request: the manual result kind branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28271

Build a bounded manual redirect result without issuing the next request: header exposure origin · case 01

Build a bounded manual redirect result without issuing the next request: the header exposure origin branch emits an incorrect decision.

HTTP redirects● Open access↗
FA-28272

Build a bounded manual redirect result without issuing the next request: header exposure origin · case 02

Build a bounded manual redirect result without issuing the next request: the header exposure origin branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28273

Build a bounded manual redirect result without issuing the next request: header exposure origin · case 03

Build a bounded manual redirect result without issuing the next request: the header exposure origin branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28274

Build a bounded manual redirect result without issuing the next request: header exposure origin · case 04

Build a bounded manual redirect result without issuing the next request: the header exposure origin branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28275

Build a bounded manual redirect result without issuing the next request: header exposure origin · case 05

Build a bounded manual redirect result without issuing the next request: the header exposure origin branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28276

Build a bounded manual redirect result without issuing the next request: body readability · case 01

Build a bounded manual redirect result without issuing the next request: the body readability branch emits an incorrect decision.

HTTP redirects● Open access↗
FA-28277

Build a bounded manual redirect result without issuing the next request: body readability · case 02

Build a bounded manual redirect result without issuing the next request: the body readability branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28278

Build a bounded manual redirect result without issuing the next request: body readability · case 03

Build a bounded manual redirect result without issuing the next request: the body readability branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28279

Build a bounded manual redirect result without issuing the next request: body readability · case 04

Build a bounded manual redirect result without issuing the next request: the body readability branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28280

Build a bounded manual redirect result without issuing the next request: body readability · case 05

Build a bounded manual redirect result without issuing the next request: the body readability branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28281

Build a bounded manual redirect result without issuing the next request: missing location not redirect · case 01

Build a bounded manual redirect result without issuing the next request: the missing location not redirect branch emits an incorrect decision.

HTTP redirects● Open access↗
FA-28282

Build a bounded manual redirect result without issuing the next request: missing location not redirect · case 02

Build a bounded manual redirect result without issuing the next request: the missing location not redirect branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28283

Build a bounded manual redirect result without issuing the next request: missing location not redirect · case 03

Build a bounded manual redirect result without issuing the next request: the missing location not redirect branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28284

Build a bounded manual redirect result without issuing the next request: missing location not redirect · case 04

Build a bounded manual redirect result without issuing the next request: the missing location not redirect branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28285

Build a bounded manual redirect result without issuing the next request: missing location not redirect · case 05

Build a bounded manual redirect result without issuing the next request: the missing location not redirect branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28286

Build a bounded manual redirect result without issuing the next request: status class report · case 01

Build a bounded manual redirect result without issuing the next request: the status class report branch emits an incorrect decision.

HTTP redirects● Open access↗
FA-28287

Build a bounded manual redirect result without issuing the next request: status class report · case 02

Build a bounded manual redirect result without issuing the next request: the status class report branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28288

Build a bounded manual redirect result without issuing the next request: status class report · case 03

Build a bounded manual redirect result without issuing the next request: the status class report branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28289

Build a bounded manual redirect result without issuing the next request: status class report · case 04

Build a bounded manual redirect result without issuing the next request: the status class report branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28290

Build a bounded manual redirect result without issuing the next request: status class report · case 05

Build a bounded manual redirect result without issuing the next request: the status class report branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28291

Expose final response metadata without leaking intermediate representation state: effective url · case 01

Expose final response metadata without leaking intermediate representation state: the effective url branch emits an incorrect decision.

HTTP redirects● Open access↗
FA-28292

Expose final response metadata without leaking intermediate representation state: effective url · case 02

Expose final response metadata without leaking intermediate representation state: the effective url branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28293

Expose final response metadata without leaking intermediate representation state: effective url · case 03

Expose final response metadata without leaking intermediate representation state: the effective url branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28294

Expose final response metadata without leaking intermediate representation state: effective url · case 04

Expose final response metadata without leaking intermediate representation state: the effective url branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28295

Expose final response metadata without leaking intermediate representation state: effective url · case 05

Expose final response metadata without leaking intermediate representation state: the effective url branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28296

Expose final response metadata without leaking intermediate representation state: final status · case 01

Expose final response metadata without leaking intermediate representation state: the final status branch emits an incorrect decision.

HTTP redirects● Open access↗
FA-28297

Expose final response metadata without leaking intermediate representation state: final status · case 02

Expose final response metadata without leaking intermediate representation state: the final status branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28298

Expose final response metadata without leaking intermediate representation state: final status · case 03

Expose final response metadata without leaking intermediate representation state: the final status branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28299

Expose final response metadata without leaking intermediate representation state: final status · case 04

Expose final response metadata without leaking intermediate representation state: the final status branch emits an incorrect decision.

HTTP redirects◈ Members↗
FA-28300

Expose final response metadata without leaking intermediate representation state: final status · case 05

Expose final response metadata without leaking intermediate representation state: the final status branch emits an incorrect decision.

HTTP redirects◈ Members↗

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 ↗