diff --git a/.gitignore b/.gitignore
index 0868be8..fcea259 100644
--- a/.gitignore
+++ b/.gitignore
@@ -13,7 +13,7 @@
 
 # WHY: Logs are useful during debugging and verification.
 # ALT: Comment if logs must be inspected or validated.
-# *.log
+*.log
 # logs/
 PRIVATE_NOTES.md
 PRIVATE-NOTES.md
diff --git a/src/datafun/app_retail_duckdb_case.py b/src/datafun/app_retail_duckdb_case.py
index 7201fd8..6f2595f 100644
--- a/src/datafun/app_retail_duckdb_case.py
+++ b/src/datafun/app_retail_duckdb_case.py
@@ -36,14 +36,14 @@
 
 ROOT_DIR: Final[Path] = Path.cwd()
 
-DATA_RAW_DIR = ROOT_DIR / "data" / "raw" / "retail"
-DATA_PROCESSED_DIR = ROOT_DIR / "data" / "processed" / "retail"
-ARTIFACTS_DIR = ROOT_DIR / "artifacts" / "duckdb"
+DATA_RAW_DIR: Final[Path] = ROOT_DIR / "data" / "raw" / "retail"
+DATA_PROCESSED_DIR: Final[Path] = ROOT_DIR / "data" / "processed" / "retail"
+ARTIFACTS_DIR: Final[Path] = ROOT_DIR / "artifacts" / "duckdb"
 SQL_DIR: Final[Path] = ROOT_DIR / "sql" / "duckdb"
 
-STORE_CSV = DATA_RAW_DIR / "store.csv"
-SALE_CSV = DATA_RAW_DIR / "sale.csv"
-DB_PATH = ARTIFACTS_DIR / "retail.duckdb"
+STORE_CSV: Final[Path] = DATA_RAW_DIR / "store.csv"
+SALE_CSV: Final[Path] = DATA_RAW_DIR / "sale.csv"
+DB_PATH: Final[Path] = ARTIFACTS_DIR / "retail.duckdb"
 
 # === DECLARE HELPER FUNCTION:  READ SQL FROM PATH ===
 
diff --git a/src/datafun/app_retail_sqlite_case.py b/src/datafun/app_retail_sqlite_case.py
index 5727370..4ee483f 100644
--- a/src/datafun/app_retail_sqlite_case.py
+++ b/src/datafun/app_retail_sqlite_case.py
@@ -39,14 +39,14 @@
 
 ROOT_DIR: Final[Path] = Path.cwd()
 
-DATA_RAW_DIR = ROOT_DIR / "data" / "raw" / "retail"
-DATA_PROCESSED_DIR = ROOT_DIR / "data" / "processed" / "retail"
-ARTIFACTS_DIR = ROOT_DIR / "artifacts" / "sqlite"
+DATA_RAW_DIR: Final[Path] = ROOT_DIR / "data" / "raw" / "retail"
+DATA_PROCESSED_DIR: Final[Path] = ROOT_DIR / "data" / "processed" / "retail"
+ARTIFACTS_DIR: Final[Path] = ROOT_DIR / "artifacts" / "sqlite"
 SQL_DIR: Final[Path] = ROOT_DIR / "sql" / "sqlite"
 
-STORE_CSV = DATA_RAW_DIR / "store.csv"
-SALE_CSV = DATA_RAW_DIR / "sale.csv"
-DB_PATH = ARTIFACTS_DIR / "retail.sqlite"
+STORE_CSV: Final[Path] = DATA_RAW_DIR / "store.csv"
+SALE_CSV: Final[Path] = DATA_RAW_DIR / "sale.csv"
+DB_PATH: Final[Path] = ARTIFACTS_DIR / "retail.sqlite"
 
 # === DECLARE HELPER FUNCTION:  READ SQL FROM PATH ===