---
phase: 04-python-efficiency
verified: 2026-03-20T09:30:00Z
status: passed
score: 3/3 must-haves verified
re_verification: false
---

# Phase 4: Python Efficiency Verification Report

**Phase Goal:** Eliminate redundant config instantiation, cache misses, and DataFrame copies.
**Verified:** 2026-03-20T09:30:00Z
**Status:** passed
**Re-verification:** No — initial verification

## Goal Achievement

### Observable Truths

| #   | Truth                                                                                                    | Status   | Evidence                                                                                                                                                                                                          |
| --- | -------------------------------------------------------------------------------------------------------- | -------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| 1   | `_kintsugi_cfg()` called once at top of `_repair()`, bound to `cfg`, reused at lines ~1001, ~1043, ~1075 | VERIFIED | `cfg = _kintsugi_cfg()` at line 996 inside `_repair()` (starts line 934); `cfg.batch_days` at 1005; `cfg.batch_workers` at 1047, 1079; zero bare `_kintsugi_cfg().batch*` calls remain                            |
| 2   | Vision 404 negative cache uses 15-min TTL for dates within 2 days of today, 1-hour TTL otherwise         | VERIFIED | `vision_probe_ttl_recent_s: int = 900` in `config/backfill.py:56`; `ttl = cfg.vision_probe_ttl_recent_s if days_ago <= 2 else cfg.vision_probe_ttl_s` in `backfill.py:102`; try/except fallback to 1h at line 104 |
| 3   | `store_bars_bulk()` non-DatetimeIndex path assigns `df = bars` instead of `df = bars.copy()`             | VERIFIED | `bulk_operations.py:503`: `df = bars  # No copy needed — store_bars_bulk is the terminal consumer (PYEF-03)`                                                                                                      |

**Score:** 3/3 truths verified

### Required Artifacts

| Artifact                                                | Expected                          | Status   | Details                                                              |
| ------------------------------------------------------- | --------------------------------- | -------- | -------------------------------------------------------------------- |
| `python/opendeviationbar/kintsugi.py`                   | Config caching in `_repair()`     | VERIFIED | `cfg = _kintsugi_cfg()` at line 996; 3 attribute accesses use `cfg.` |
| `python/opendeviationbar/backfill.py`                   | Dynamic Vision TTL                | VERIFIED | `vision_probe_ttl_recent_s` used at line 102 with 2-day window       |
| `python/opendeviationbar/config/backfill.py`            | `vision_probe_ttl_recent_s` field | VERIFIED | Line 56: `vision_probe_ttl_recent_s: int = 900  # 15 minutes`        |
| `python/opendeviationbar/clickhouse/bulk_operations.py` | Removed redundant copy            | VERIFIED | Line 503: `df = bars` with explanatory comment; `bars.copy()` absent |

### Key Link Verification

| From          | To                   | Via                                                 | Status | Details                                                                                                                |
| ------------- | -------------------- | --------------------------------------------------- | ------ | ---------------------------------------------------------------------------------------------------------------------- |
| `kintsugi.py` | `config/kintsugi.py` | `cfg = _kintsugi_cfg()` once, attributes from local | WIRED  | `cfg.batch_days` (line 1005), `cfg.batch_workers` (lines 1047, 1079); no bare `.batch*` calls remaining in `_repair()` |
| `backfill.py` | `config/backfill.py` | `vision_probe_ttl_recent_s` config field            | WIRED  | `cfg = _backfill_cfg()` at line 98, `cfg.vision_probe_ttl_recent_s` at line 102                                        |

### Requirements Coverage

| Requirement | Source Plan | Description                                                                        | Status    | Evidence                                                                                    |
| ----------- | ----------- | ---------------------------------------------------------------------------------- | --------- | ------------------------------------------------------------------------------------------- |
| PYEF-01     | 04-01-PLAN  | `_kintsugi_cfg()` called once per `_repair()`, not 3x per shard                    | SATISFIED | `cfg = _kintsugi_cfg()` at kintsugi.py:996; 3 `cfg.` attribute accesses; zero bare calls    |
| PYEF-02     | 04-01-PLAN  | Vision 404 negative cache TTL reduced to 15min for T-1 dates                       | SATISFIED | `vision_probe_ttl_recent_s = 900` in config; dynamic branch in `_mark_vision_unavailable()` |
| PYEF-03     | 04-01-PLAN  | `store_bars_bulk()` removes redundant `df = bars.copy()` on non-DatetimeIndex path | SATISFIED | `df = bars` at bulk_operations.py:503; no `bars.copy()` present                             |

No orphaned requirements. All three PYEF requirements for Phase 4 are mapped and satisfied. REQUIREMENTS.md traceability table confirms Phase 4 = Complete for PYEF-01/02/03.

### Anti-Patterns Found

None. Scanned all four modified files for TODO/FIXME/placeholder markers and empty implementations. No issues found. The change at `bulk_operations.py:503` includes an explanatory comment documenting the safety rationale.

### Human Verification Required

None. All three changes are pure data-path mutations verifiable by static analysis:

- Config caching: grep confirms binding + attribute usage pattern
- Dynamic TTL: grep confirms field exists and branch logic is implemented
- Copy removal: grep confirms `bars.copy()` is absent, `df = bars` is present

### Gaps Summary

No gaps. All three must-haves are fully implemented, wired, and free of anti-patterns. The two task commits (`9bcecfc`, `8ab09b2`) are present in git history and the REQUIREMENTS.md traceability table marks all three PYEF requirements Complete for Phase 4.

---

_Verified: 2026-03-20T09:30:00Z_
_Verifier: Claude (gsd-verifier)_
