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
Beverton-Holt recruitment convergence: initial state check · case 01
A stock that starts at equilibrium is reported as converging in year 1.
Beverton-Holt recruitment convergence: initial state check · case 02
A stock that starts at equilibrium is reported as converging in year 1.
Beverton-Holt recruitment convergence: initial state check · case 03
A stock that starts at equilibrium is reported as converging in year 1.
Beverton-Holt recruitment convergence: initial state check · case 04
A stock that starts at equilibrium is reported as converging in year 1.
Beverton-Holt recruitment convergence: initial state check · case 05
A stock that starts at equilibrium is reported as converging in year 1.
Lotka-Volterra predator-prey Euler integration: simultaneous derivative state · case 01
Predator growth responds to prey that were already updated in the same step.
Lotka-Volterra predator-prey Euler integration: simultaneous derivative state · case 02
Predator growth responds to prey that were already updated in the same step.
Lotka-Volterra predator-prey Euler integration: simultaneous derivative state · case 03
Predator growth responds to prey that were already updated in the same step.
Lotka-Volterra predator-prey Euler integration: simultaneous derivative state · case 04
Predator growth responds to prey that were already updated in the same step.
Lotka-Volterra predator-prey Euler integration: simultaneous derivative state · case 05
Predator growth responds to prey that were already updated in the same step.
Lotka-Volterra predator-prey Euler integration: conversion efficiency · case 01
Predators gain one individual per prey eaten regardless of conversion efficiency.
Lotka-Volterra predator-prey Euler integration: conversion efficiency · case 02
Predators gain one individual per prey eaten regardless of conversion efficiency.
Lotka-Volterra predator-prey Euler integration: conversion efficiency · case 03
Predators gain one individual per prey eaten regardless of conversion efficiency.
Lotka-Volterra predator-prey Euler integration: conversion efficiency · case 04
Predators gain one individual per prey eaten regardless of conversion efficiency.
Lotka-Volterra predator-prey Euler integration: conversion efficiency · case 05
Predators gain one individual per prey eaten regardless of conversion efficiency.
Lotka-Volterra predator-prey Euler integration: predator mortality · case 01
Predator mortality is a constant loss that drives small populations negative.
Lotka-Volterra predator-prey Euler integration: predator mortality · case 02
Predator mortality is a constant loss that drives small populations negative.
Lotka-Volterra predator-prey Euler integration: predator mortality · case 03
Predator mortality is a constant loss that drives small populations negative.
Lotka-Volterra predator-prey Euler integration: predator mortality · case 04
Predator mortality is a constant loss that drives small populations negative.
Lotka-Volterra predator-prey Euler integration: predator mortality · case 05
Predator mortality is a constant loss that drives small populations negative.
Lotka-Volterra predator-prey Euler integration: equilibrium coordinates · case 01
The reported coexistence point has prey and predator swapped.
Lotka-Volterra predator-prey Euler integration: equilibrium coordinates · case 02
The reported coexistence point has prey and predator swapped.
Lotka-Volterra predator-prey Euler integration: equilibrium coordinates · case 03
The reported coexistence point has prey and predator swapped.
Lotka-Volterra predator-prey Euler integration: equilibrium coordinates · case 04
The reported coexistence point has prey and predator swapped.
Lotka-Volterra predator-prey Euler integration: equilibrium coordinates · case 05
The reported coexistence point has prey and predator swapped.
Lotka-Volterra predator-prey Euler integration: non-negativity floor · case 01
Large steps drive prey negative, which then feeds predators negatively.
Lotka-Volterra predator-prey Euler integration: non-negativity floor · case 02
Large steps drive prey negative, which then feeds predators negatively.
Lotka-Volterra predator-prey Euler integration: non-negativity floor · case 03
Large steps drive prey negative, which then feeds predators negatively.
Lotka-Volterra predator-prey Euler integration: non-negativity floor · case 04
Large steps drive prey negative, which then feeds predators negatively.
Lotka-Volterra predator-prey Euler integration: non-negativity floor · case 05
Large steps drive prey negative, which then feeds predators negatively.
Holling functional response consumption: type I satiation cap · case 01
Filter feeders are capped at the handling time instead of the maximum intake rate.
Holling functional response consumption: type I satiation cap · case 02
Filter feeders are capped at the handling time instead of the maximum intake rate.
Holling functional response consumption: type I satiation cap · case 03
Filter feeders are capped at the handling time instead of the maximum intake rate.
Holling functional response consumption: type I satiation cap · case 04
Filter feeders are capped at the handling time instead of the maximum intake rate.
Holling functional response consumption: type I satiation cap · case 05
Filter feeders are capped at the handling time instead of the maximum intake rate.
Holling functional response consumption: type II handling term · case 01
Intake saturates at the wrong prey density.
Holling functional response consumption: type II handling term · case 02
Intake saturates at the wrong prey density.
Holling functional response consumption: type II handling term · case 03
Intake saturates at the wrong prey density.
Holling functional response consumption: type II handling term · case 04
Intake saturates at the wrong prey density.
Holling functional response consumption: type II handling term · case 05
Intake saturates at the wrong prey density.
Holling functional response consumption: type III sigmoid · case 01
Type III intake rises without bound instead of saturating.
Holling functional response consumption: type III sigmoid · case 02
Type III intake rises without bound instead of saturating.
Holling functional response consumption: type III sigmoid · case 03
Type III intake rises without bound instead of saturating.
Holling functional response consumption: type III sigmoid · case 04
Type III intake rises without bound instead of saturating.
Holling functional response consumption: type III sigmoid · case 05
Type III intake rises without bound instead of saturating.
Holling functional response consumption: prey depletion cap · case 01
More prey are eaten than exist.
Holling functional response consumption: prey depletion cap · case 02
More prey are eaten than exist.
Holling functional response consumption: prey depletion cap · case 03
More prey are eaten than exist.
Holling functional response consumption: prey depletion cap · case 04
More prey are eaten than exist.
Holling functional response consumption: prey depletion cap · case 05
More prey are eaten than exist.
Leslie matrix projection with optional plus group: fecundity row · case 01
Births stay fixed at the initial level every year.
Leslie matrix projection with optional plus group: fecundity row · case 02
Births stay fixed at the initial level every year.
Leslie matrix projection with optional plus group: fecundity row · case 03
Births stay fixed at the initial level every year.
Leslie matrix projection with optional plus group: fecundity row · case 04
Births stay fixed at the initial level every year.
Leslie matrix projection with optional plus group: fecundity row · case 05
Births stay fixed at the initial level every year.
Leslie matrix projection with optional plus group: survival subdiagonal · case 01
Classes age without moving: survivors come from the destination class.
Leslie matrix projection with optional plus group: survival subdiagonal · case 02
Classes age without moving: survivors come from the destination class.
Leslie matrix projection with optional plus group: survival subdiagonal · case 03
Classes age without moving: survivors come from the destination class.
Leslie matrix projection with optional plus group: survival subdiagonal · case 04
Classes age without moving: survivors come from the destination class.
Leslie matrix projection with optional plus group: survival subdiagonal · case 05
Classes age without moving: survivors come from the destination class.
Leslie matrix projection with optional plus group: plus group retention · case 01
The plus group loses all incoming recruits from the previous class.
Leslie matrix projection with optional plus group: plus group retention · case 02
The plus group loses all incoming recruits from the previous class.
Leslie matrix projection with optional plus group: plus group retention · case 03
The plus group loses all incoming recruits from the previous class.
Leslie matrix projection with optional plus group: plus group retention · case 04
The plus group loses all incoming recruits from the previous class.
Leslie matrix projection with optional plus group: plus group retention · case 05
The plus group loses all incoming recruits from the previous class.
Leslie matrix projection with optional plus group: growth ratio base · case 01
The reported annual growth ratio is really growth since the initial year, or a stale total.
Leslie matrix projection with optional plus group: growth ratio base · case 02
The reported annual growth ratio is really growth since the initial year, or a stale total.
Leslie matrix projection with optional plus group: growth ratio base · case 03
The reported annual growth ratio is really growth since the initial year, or a stale total.
Leslie matrix projection with optional plus group: growth ratio base · case 04
The reported annual growth ratio is really growth since the initial year, or a stale total.
Leslie matrix projection with optional plus group: growth ratio base · case 05
The reported annual growth ratio is really growth since the initial year, or a stale total.
Leslie matrix projection with optional plus group: extinct ratio · case 01
An already-extinct population reports a growth ratio.
Leslie matrix projection with optional plus group: extinct ratio · case 02
An already-extinct population reports a growth ratio.
Leslie matrix projection with optional plus group: extinct ratio · case 03
An already-extinct population reports a growth ratio.
Leslie matrix projection with optional plus group: extinct ratio · case 04
An already-extinct population reports a growth ratio.
Leslie matrix projection with optional plus group: extinct ratio · case 05
An already-extinct population reports a growth ratio.
Cohort life table statistics: survivorship accumulation · case 01
Survivorship rises again after a bad year.
Cohort life table statistics: survivorship accumulation · case 02
Survivorship rises again after a bad year.
Cohort life table statistics: survivorship accumulation · case 03
Survivorship rises again after a bad year.
Cohort life table statistics: survivorship accumulation · case 04
Survivorship rises again after a bad year.
Cohort life table statistics: survivorship accumulation · case 05
Survivorship rises again after a bad year.
Cohort life table statistics: net reproductive rate · case 01
R0 ignores mortality before breeding.
Cohort life table statistics: net reproductive rate · case 02
R0 ignores mortality before breeding.
Cohort life table statistics: net reproductive rate · case 03
R0 ignores mortality before breeding.
Cohort life table statistics: net reproductive rate · case 04
R0 ignores mortality before breeding.
Cohort life table statistics: net reproductive rate · case 05
R0 ignores mortality before breeding.
Cohort life table statistics: generation time weighting · case 01
Generation time is one year too long.
Cohort life table statistics: generation time weighting · case 02
Generation time is one year too long.
Cohort life table statistics: generation time weighting · case 03
Generation time is one year too long.
Cohort life table statistics: generation time weighting · case 04
Generation time is one year too long.
Cohort life table statistics: generation time weighting · case 05
Generation time is one year too long.
Cohort life table statistics: intrinsic rate · case 01
Intrinsic growth is overstated for strongly growing cohorts.
Cohort life table statistics: intrinsic rate · case 02
Intrinsic growth is overstated for strongly growing cohorts.
Cohort life table statistics: intrinsic rate · case 03
Intrinsic growth is overstated for strongly growing cohorts.
Cohort life table statistics: intrinsic rate · case 04
Intrinsic growth is overstated for strongly growing cohorts.
Cohort life table statistics: intrinsic rate · case 05
Intrinsic growth is overstated for strongly growing cohorts.
Cohort life table statistics: life expectancy trapezoid · case 01
Life expectancy ignores that deaths occur during the interval.
Cohort life table statistics: life expectancy trapezoid · case 02
Life expectancy ignores that deaths occur during the interval.
Cohort life table statistics: life expectancy trapezoid · case 03
Life expectancy ignores that deaths occur during the interval.
Cohort life table statistics: life expectancy trapezoid · case 04
Life expectancy ignores that deaths occur during the interval.
Cohort life table statistics: life expectancy trapezoid · case 05
Life expectancy ignores that deaths occur during the interval.
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 ↗