diff --git a/src/node/utils/getGitTimestamp.ts b/src/node/utils/getGitTimestamp.ts
index 1b62c5b1..463379b5 100644
--- a/src/node/utils/getGitTimestamp.ts
+++ b/src/node/utils/getGitTimestamp.ts
@@ -3,7 +3,7 @@ import fs from 'node:fs'
 import path from 'node:path'
 import { slash } from '../shared'
 
-let cache = new Map<string, number>()
+const cache = new Map<string, number>()
 
 const RS = 0x1e
 const NUL = 0x00