| Find and fix an event listener leak | hard-targeting | pass | 28.3s | 63.8k | $0.021 | — | yes |
| Rename a public function across the codebase | hard-targeting | pass | 30.5s | 93.5k | $0.030 | — | yes |
| Fix concurrent counter race condition | hard-targeting | pass | 35.9s | 59.7k | $0.021 | — | yes |
| Restore linear performance in a hot loop | hard-targeting | pass | 2m 50s | 87.7k | $0.027 | — | yes |
| Add an options parameter to format() without breaking callers | hard-targeting | pass | 2m 0s | 202.6k | $0.063 | — | yes |
| Read SPEC.md and implement the right behavior | hard-targeting | pass | 32.0s | 60.9k | $0.019 | — | yes |
| Two parsers disagree on the same config file | hard-targeting | pass | 42.6s | 36.7k | $0.013 | — | yes |
| Migrate from fs.readFile(callback) to fs.promises.readFile() | hard-targeting | pass | 2m 11s | 86.5k | $0.034 | — | yes |
| Fix implicit string→number coercion in comparison | hard-targeting | pass | 27.2s | 81.3k | $0.026 | — | yes |
| A test passes for the wrong reason — find the real fix | hard-targeting | pass | 1m 56s | 80.5k | $0.031 | — | yes |
| Find and fix an event listener leak | hard-targeting | pass | 31.0s | 61.0k | $0.019 | — | yes |
| Debug an off-by-one in binary search | harder | pass | 40.2s | 62.9k | $0.020 | — | yes |
| Debug an off-by-one in binary search | harder | done | 5m 44s | 71.7k | $0.025 | — | yes |
| Fix off-by-one in interval overlap detector | harder | done | 50.8s | 40.1k | $0.014 | — | yes |
| Fix the async cache stampede | harder | done | 1m 7s | 51.9k | $0.018 | — | yes |
| Rename `process` → `handle` across 4 files | harder | done | 1m 54s | 69.4k | $0.024 | — | yes |
| Extract `validateAmount` from `submit` | harder | done | 1m 1s | 59.1k | $0.020 | — | yes |
| Split src/store.js into store + selectors | harder | done | 1m 44s | 68.3k | $0.024 | — | yes |
| Build a token-bucket limiter with exact semantics | harder | done | 8m 49s | 486.5k | $0.168 | — | yes |
| Implement formatDuration(ms) with strict spec | harder | done | 1m 56s | 107.3k | $0.037 | — | yes |
| Implement deepEqual with cycle detection | harder | done | 2m 7s | 155.0k | $0.053 | — | yes |
| Test the groupBy implementation | harder | done | 3m 44s | 196.5k | $0.068 | — | yes |
| Test the flatten implementation | harder | done | 1m 49s | 154.6k | $0.053 | — | yes |
| Test the debounce implementation | harder | done | 4m 46s | 592.3k | $0.204 | — | yes |
| Debug an off-by-one in binary search | harder | done | 10m 41s | 33.4k | $0.012 | — | yes |
| Fix off-by-one in interval overlap detector | harder | done | 54.9s | 61.7k | $0.021 | — | yes |
| Fix the async cache stampede | harder | pass | 1m 5s | 50.8k | $0.018 | — | yes |
| Rename `process` → `handle` across 4 files | harder | done | 1m 6s | 63.0k | $0.022 | — | yes |
| Extract `validateAmount` from `submit` | harder | done | 1m 12s | 62.4k | $0.022 | — | yes |
| Split src/store.js into store + selectors | harder | done | 45.9s | 45.3k | $0.016 | — | yes |
| Build a token-bucket limiter with exact semantics | harder | timeout | 13m 4s | - | — | — | - |
| Implement formatDuration(ms) with strict spec | harder | pass | 1m 3s | 64.3k | $0.022 | — | yes |
| Implement deepEqual with cycle detection | harder | done | 1m 57s | 76.8k | $0.026 | — | yes |
| Test the groupBy implementation | harder | done | 2m 40s | 142.6k | $0.049 | — | yes |
| Test the flatten implementation | harder | failed | 1m 59s | 87.5k | $0.030 | — | yes |
| Test the debounce implementation | harder | done | 3m 6s | 165.0k | $0.057 | — | yes |
| Debug an off-by-one in binary search | harder | done | 5m 46s | 62.3k | $0.021 | — | yes |
| Fix off-by-one in interval overlap detector | harder | done | 1m 1s | 52.7k | $0.018 | — | yes |
| Fix the async cache stampede | harder | pass | 57.3s | 50.3k | $0.017 | — | yes |
| Rename `process` → `handle` across 4 files | harder | done | 1m 50s | 59.7k | $0.021 | — | yes |
| Extract `validateAmount` from `submit` | harder | done | 1m 6s | 88.4k | $0.031 | — | yes |
| Split src/store.js into store + selectors | harder | done | 1m 4s | 50.8k | $0.018 | — | yes |
| Build a token-bucket limiter with exact semantics | harder | timeout | 13m 4s | - | — | — | - |
| Implement formatDuration(ms) with strict spec | harder | done | 1m 28s | 66.4k | $0.023 | — | yes |
| Implement deepEqual with cycle detection | harder | done | 2m 26s | 79.9k | $0.028 | — | yes |
| Test the groupBy implementation | harder | done | 2m 54s | 206.2k | $0.071 | — | yes |
| Test the flatten implementation | harder | done | 1m 56s | 234.1k | $0.081 | — | yes |
| Test the debounce implementation | harder | done | 1m 28s | 170.6k | $0.059 | — | yes |