{
  "date": "2026-10-16",
  "issue": 237,
  "admitted": false,
  "decision": "Reject generic Java array conversion; retain released Flink converter and Unicode ARRAY_SORT regression.",
  "base_revision": "b170a474d5658330ed7e92e9b8bcc54117c8d287",
  "source_identity": "Uncommitted nested-scalar prototype; complete original working-tree snapshot was not retained. These profiles precede the native key/UNNEST/order metadata fixes. Not admission or exact-final-head evidence.",
  "native_base_sha256": "d55c5bfa509c460a84c76c9bc2b62a4a46575cec32ff4d905847a1e66c4bd786",
  "native_build": "release with mimalloc; unchanged baseline for both profiles",
  "configuration": {
    "java": "JDK 17",
    "flink": "2.2.1",
    "heap": "2 GiB",
    "rows_per_shape": 1000000,
    "shapes": [
      "identity",
      "transform",
      "rust builtin control"
    ],
    "warmup_pairs": 2,
    "measured_pairs": 3,
    "parallelism": 1,
    "width": 16,
    "production_ipc": true,
    "both_transposes": true,
    "profiling": "async-profiler 4.0 cpu-clock interval 2 ms, cstack=dwarf, Java allocation interval 1 MiB"
  },
  "limitations": [
    "ALL profile timings excluded; external Java activity observed during both recordings.",
    "Java allocation estimates are not copied bytes, native allocation volume or retained memory.",
    "Whole-process recordings include warmup, setup, JIT and a separate primitive Rust-control shape. Inclusive stack totals overlap.",
    "Callback allocation reduction does not establish correctness or throughput. The candidate changes ARRAY_SORT Unicode order and is rejected."
  ],
  "profiles": [
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      "label": "nested-scalar-first",
      "exit_code": 0,
      "profile_timing_excluded": true,
      "external_cpu_seconds": 63.06,
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          }
        },
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          }
        }
      }
    },
    {
      "label": "nested-scalar-generic",
      "exit_code": 0,
      "profile_timing_excluded": true,
      "external_cpu_seconds": 72.46,
      "external_observations": 81,
      "files": [
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            "row_to_external": 1827667968,
            "rust_calc": 0,
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          }
        }
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  "rejected_converter": {
    "file": "nested-scalar-rejected-converter-2026-10-16.java.gz",
    "sha256": "4903f72de771ced19509a462e3362843e79320634b38c5e6500419ff082a7b53"
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  "sampled_callback_allocation_reduction": 0.2217155120380927,
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    "file": "nested-scalar-rejected-unicode-order-2026-10-16.log.gz",
    "sha256": "767fc877bfe999970e4c9f54a6db38fa6057bec82b3f3506f9acdfd74bc1c5cd"
  }
}