diff --git a/.jules/bolt.md b/.jules/bolt.md
index 5047f271..20bdfb8a 100644
--- a/.jules/bolt.md
+++ b/.jules/bolt.md
@@ -34,3 +34,6 @@
 ## 2024-07-11 - Iterative JSON Extraction vs Recursion
 **Learning:** In `scripts/ci/opencode_review_normalize_output.py`, deeply recursive nested data processing for extracting JSON dictionaries (such as with LLM outputs where structure is arbitrary) using a recursive `extract_dicts` function causes Python to hit max recursion depth (`RecursionError`) on sufficiently deep structures, and increases runtime overhead due to call stack memory allocations.
 **Action:** When extracting data from arbitrary deeply nested dictionaries and lists in Python, use an iterative stack-based approach with `stack.extend()` or `stack.extend(reversed(...))` instead of recursive functions to eliminate recursion depth limitations and reduce overhead.
+## 2024-07-25 - Pre-calculate and cache environmental file reads
+**Learning:** The `current_changed_files` function in `scripts/ci/opencode_review_normalize_output.py` was being called multiple times per item during JSON structure normalization, leading to redundant I/O reads of `OPENCODE_CHANGED_FILES_FILE`.
+**Action:** Use `@functools.lru_cache(maxsize=1)` and return an immutable `frozenset` when repeatedly reading static contextual files within a script's execution lifecycle.
diff --git a/scripts/ci/opencode_review_normalize_output.py b/scripts/ci/opencode_review_normalize_output.py
index cd46d266..91e99ed7 100755
--- a/scripts/ci/opencode_review_normalize_output.py
+++ b/scripts/ci/opencode_review_normalize_output.py
@@ -7,6 +7,7 @@
 import os
 import re
 import sys
+from functools import lru_cache
 from pathlib import Path
 from typing import Any
 
@@ -307,21 +308,22 @@ def mentions_changed_file_evidence(reason: str, summary: str) -> bool:
     return bool(CHANGED_FILE_EVIDENCE_PATTERN.search(f"{reason}\n{summary}"))
 
 
-def current_changed_files() -> set[str]:
+@lru_cache(maxsize=1)
+def current_changed_files() -> frozenset[str]:
     """Return the exact current-head changed files when the workflow provides them."""
     changed_files_path = os.environ.get("OPENCODE_CHANGED_FILES_FILE")
     if not changed_files_path:
-        return set()
+        return frozenset()
     try:
-        return {
+        return frozenset(
             line.strip()
             for line in Path(changed_files_path)
             .read_text(encoding="utf-8")
             .splitlines()
             if line.strip()
-        }
+        )
     except OSError:
-        return set()
+        return frozenset()
 
 
 def changed_file_is_source_like(path: str) -> bool:
diff --git a/tests/test_opencode_review_normalize_output.py b/tests/test_opencode_review_normalize_output.py
index fc317101..bc77c3a4 100644
--- a/tests/test_opencode_review_normalize_output.py
+++ b/tests/test_opencode_review_normalize_output.py
@@ -1,8 +1,15 @@
 import json
 
+import pytest
+
 from scripts.ci import opencode_review_normalize_output as norm
 
 
+@pytest.fixture(autouse=True)
+def clear_caches():
+    norm.current_changed_files.cache_clear()
+
+
 FULL_SUMMARY = """\
 Approval sufficiency: affirmative evidence supported approval beyond the absence of blockers.
 Verification posture: CodeGraph inspected scripts/ci/example.py on the current head.
@@ -92,7 +99,8 @@ def test_changed_file_and_verification_posture_detection():
 
 def test_actual_changed_file_detection_prefers_current_head_file_list(tmp_path, monkeypatch):
     monkeypatch.delenv("OPENCODE_CHANGED_FILES_FILE", raising=False)
-    assert norm.current_changed_files() == set()
+    norm.current_changed_files.cache_clear()
+    assert norm.current_changed_files() == frozenset()
     assert norm.mentions_actual_changed_file("scripts/ci/example.py", "")
 
     changed_files = tmp_path / "changed-files.txt"
@@ -107,8 +115,10 @@ def test_actual_changed_file_detection_prefers_current_head_file_list(tmp_path,
         encoding="utf-8",
     )
     monkeypatch.setenv("OPENCODE_CHANGED_FILES_FILE", str(changed_files))
+    norm.current_changed_files.cache_clear()
 
     monkeypatch.delenv("OPENCODE_CHANGED_FILES_FILE", raising=False)
+    norm.current_changed_files.cache_clear()
     assert norm.mentions_actual_changed_file("No executable changes here", "no changed files")
     assert norm.mentions_verification_posture("No executable changes here", "no changed files")
     assert norm.mentions_full_coverage("No executable changes here", "no changed files")
@@ -119,12 +129,13 @@ def test_actual_changed_file_detection_prefers_current_head_file_list(tmp_path,
     assert norm.mentions_verification_posture("No UI codebase changes", "No UI codebase changes")
     assert norm.mentions_full_coverage("No UI codebase changes", "No UI codebase changes")
     monkeypatch.setenv("OPENCODE_CHANGED_FILES_FILE", str(changed_files))
+    norm.current_changed_files.cache_clear()
 
 
-    assert norm.current_changed_files() == {
+    assert norm.current_changed_files() == frozenset({
         ".github/workflows/opencode-review.yml",
         "scripts/ci/opencode_review_normalize_output.py",
-    }
+    })
     assert norm.mentions_actual_changed_file(
         "Reviewed .github/workflows/opencode-review.yml.",
         "",
@@ -139,7 +150,8 @@ def test_actual_changed_file_detection_prefers_current_head_file_list(tmp_path,
     )
 
     monkeypatch.setenv("OPENCODE_CHANGED_FILES_FILE", str(tmp_path / "missing.txt"))
-    assert norm.current_changed_files() == set()
+    norm.current_changed_files.cache_clear()
+    assert norm.current_changed_files() == frozenset()
     assert norm.mentions_actual_changed_file("scripts/ci/example.py", "")
 
 
@@ -149,6 +161,7 @@ def test_preferred_review_language_handles_unreadable_and_unknown_evidence(tmp_p
         "## Review language evidence\nPreferred review language: `Spanish`\n",
         encoding="utf-8",
     )
+    norm.current_changed_files.cache_clear()
     monkeypatch.setenv("OPENCODE_APPROVAL_REPAIR_EVIDENCE_FILE", str(evidence))
 
     assert norm.preferred_review_language() is None
@@ -169,6 +182,7 @@ def test_changed_file_kind_contradictions_are_rejected(tmp_path, monkeypatch):
         encoding="utf-8",
     )
     monkeypatch.setenv("OPENCODE_CHANGED_FILES_FILE", str(changed_files))
+    norm.current_changed_files.cache_clear()
 
     false_summary = (
         FULL_SUMMARY.replace("scripts/ci/example.py", ".github/workflows/opencode-review.yml")
@@ -227,6 +241,7 @@ def test_changed_file_kind_contradictions_are_rejected(tmp_path, monkeypatch):
     )
 
     monkeypatch.delenv("OPENCODE_CHANGED_FILES_FILE")
+    norm.current_changed_files.cache_clear()
     assert not norm.contradicts_changed_file_kinds(approval["reason"], approval["summary"])
 
 
@@ -243,6 +258,7 @@ def test_material_changed_file_scope_rejects_trivial_string_approval(tmp_path, m
         encoding="utf-8",
     )
     monkeypatch.setenv("OPENCODE_CHANGED_FILES_FILE", str(changed_files))
+    norm.current_changed_files.cache_clear()
 
     summary = (
         "Approval sufficiency: The change is a simple typo fix in a string with no functional impact. "
@@ -276,6 +292,7 @@ def test_material_changed_file_scope_rejects_trivial_string_approval(tmp_path, m
     assert norm.check_structural_approval(path) == 4
 
     changed_files.write_text("README.md\n", encoding="utf-8")
+    norm.current_changed_files.cache_clear()
     assert not norm.contradicts_material_changed_file_scope(
         approval["reason"],
         approval["summary"],
@@ -295,6 +312,7 @@ def test_material_changed_file_scope_rejects_false_documentation_typo_reason(tmp
         encoding="utf-8",
     )
     monkeypatch.setenv("OPENCODE_CHANGED_FILES_FILE", str(changed_files))
+    norm.current_changed_files.cache_clear()
 
     approval = control(
         reason="Typo fix in documentation string",
@@ -400,10 +418,12 @@ def test_check_structural_approval_rejects_invalid_or_unsafe_approvals(tmp_path,
     changed_files = tmp_path / "changed-files.txt"
     changed_files.write_text("tests/actual_changed_file.py\n", encoding="utf-8")
     monkeypatch.setenv("OPENCODE_CHANGED_FILES_FILE", str(changed_files))
+    norm.current_changed_files.cache_clear()
     wrong_file = tmp_path / "wrong-file.json"
     wrong_file.write_text(json.dumps(control()), encoding="utf-8")
     assert norm.check_structural_approval(wrong_file) == 4
     monkeypatch.delenv("OPENCODE_CHANGED_FILES_FILE")
+    norm.current_changed_files.cache_clear()
 
     request_changes = tmp_path / "request.json"
     request_changes.write_text(json.dumps(control(result="REQUEST_CHANGES")), encoding="utf-8")
@@ -526,6 +546,7 @@ def test_valid_control_repairs_approval_summary_from_bounded_evidence(tmp_path,
 """,
         encoding="utf-8",
     )
+    norm.current_changed_files.cache_clear()
     monkeypatch.setenv("OPENCODE_APPROVAL_REPAIR_EVIDENCE_FILE", str(evidence))
 
     repaired = norm.valid_control(
@@ -557,6 +578,7 @@ def test_valid_control_repairs_summary_from_invalid_utf8_evidence(tmp_path, monk
         b"## Changed files\n\n"
         b"M\tscripts/ci/opencode_review_normalize_output.py\n"
     )
+    norm.current_changed_files.cache_clear()
     monkeypatch.setenv("OPENCODE_APPROVAL_REPAIR_EVIDENCE_FILE", str(evidence))
 
     repaired = norm.valid_control(
@@ -604,11 +626,13 @@ def test_valid_control_repairs_fragile_approval_reason_from_bounded_evidence(tmp
 """,
         encoding="utf-8",
     )
+    norm.current_changed_files.cache_clear()
     monkeypatch.setenv("OPENCODE_EVIDENCE_FILE", str(evidence))
     monkeypatch.delenv("OPENCODE_APPROVAL_REPAIR_EVIDENCE_FILE", raising=False)
     changed_files = tmp_path / "changed-files.txt"
     changed_files.write_text(".github/workflows/r.yml\n", encoding="utf-8")
     monkeypatch.setenv("OPENCODE_CHANGED_FILES_FILE", str(changed_files))
+    norm.current_changed_files.cache_clear()
 
     repaired = norm.valid_control(
         control(
@@ -665,6 +689,7 @@ def test_valid_control_repair_overrides_earlier_invalid_coverage_labels(tmp_path
 """,
         encoding="utf-8",
     )
+    norm.current_changed_files.cache_clear()
     monkeypatch.setenv("OPENCODE_APPROVAL_REPAIR_EVIDENCE_FILE", str(evidence))
 
     repaired = norm.valid_control(
@@ -731,8 +756,10 @@ def test_valid_control_repair_drops_contradictory_changed_file_kind_claims(tmp_p
         "apps/desktop/src/App.tsx\napps/desktop/src/App.test.tsx\n",
         encoding="utf-8",
     )
+    norm.current_changed_files.cache_clear()
     monkeypatch.setenv("OPENCODE_APPROVAL_REPAIR_EVIDENCE_FILE", str(evidence))
     monkeypatch.setenv("OPENCODE_CHANGED_FILES_FILE", str(changed_files))
+    norm.current_changed_files.cache_clear()
 
     repaired = norm.valid_control(
         control(
@@ -799,8 +826,10 @@ def test_valid_control_repair_drops_material_trivialization(tmp_path, monkeypatc
         ".github/workflows/strix.yml\nscripts/ci/test_strix_quick_gate.sh\n",
         encoding="utf-8",
     )
+    norm.current_changed_files.cache_clear()
     monkeypatch.setenv("OPENCODE_APPROVAL_REPAIR_EVIDENCE_FILE", str(evidence))
     monkeypatch.setenv("OPENCODE_CHANGED_FILES_FILE", str(changed_files))
+    norm.current_changed_files.cache_clear()
 
     repaired = norm.valid_control(
         control(
@@ -845,6 +874,7 @@ def test_valid_control_does_not_repair_unsafe_or_unproven_approval(tmp_path, mon
 """,
         encoding="utf-8",
     )
+    norm.current_changed_files.cache_clear()
     monkeypatch.setenv("OPENCODE_APPROVAL_REPAIR_EVIDENCE_FILE", str(evidence))
     kwargs = {
         "expected_head_sha": "head",
@@ -949,6 +979,7 @@ def test_approval_repair_evidence_helpers_cover_edge_cases(tmp_path, monkeypatch
 
     evidence = tmp_path / "bounded-review-evidence.md"
     evidence.write_text("placeholder", encoding="utf-8")
+    norm.current_changed_files.cache_clear()
     monkeypatch.setenv("OPENCODE_APPROVAL_REPAIR_EVIDENCE_FILE", str(evidence))
     original_read_text = norm.Path.read_text
 
@@ -978,6 +1009,7 @@ def test_approval_language_contract_runs_after_evidence_repair(tmp_path, monkeyp
 """,
         encoding="utf-8",
     )
+    norm.current_changed_files.cache_clear()
     monkeypatch.setenv("OPENCODE_APPROVAL_REPAIR_EVIDENCE_FILE", str(evidence))
 
     reviewed = norm.valid_control(
@@ -1017,6 +1049,7 @@ def test_request_changes_still_enforces_korean_language_contract(tmp_path, monke
 """,
         encoding="utf-8",
     )
+    norm.current_changed_files.cache_clear()
     monkeypatch.setenv("OPENCODE_APPROVAL_REPAIR_EVIDENCE_FILE", str(evidence))
 
     assert (
@@ -1151,6 +1184,7 @@ def test_review_language_contract_rejects_english_only_korean_pr(tmp_path, monke
         "## Review language evidence\n\n- Preferred review language: `Korean`\n",
         encoding="utf-8",
     )
+    norm.current_changed_files.cache_clear()
     monkeypatch.setenv("OPENCODE_EVIDENCE_FILE", str(evidence))
 
     assert norm.valid_control(