diff --git a/package-lock.json b/package-lock.json
index bad2eb6..c515ed9 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -26,7 +26,7 @@
         "express": "4.22.1",
         "mocha": "10.8.2",
         "nyc": "17.1.0",
-        "sinon": "18.0.1",
+        "sinon": "21.0.1",
         "standard": "17.1.2"
       }
     },
@@ -61,6 +61,7 @@
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       "dev": true,
       "license": "MIT",
+      "peer": true,
       "dependencies": {
         "@babel/code-frame": "^7.29.0",
         "@babel/generator": "^7.29.0",
@@ -707,13 +708,13 @@
       }
     },
     "node_modules/@sinonjs/fake-timers": {
-      "version": "11.2.2",
-      "resolved": "https://registry.npmjs.org/@sinonjs/fake-timers/-/fake-timers-11.2.2.tgz",
-      "integrity": "sha512-G2piCSxQ7oWOxwGSAyFHfPIsyeJGXYtc6mFbnFA+kRXkiEnTl8c/8jul2S329iFBnDI9HGoeWWAZvuvOkZccgw==",
+      "version": "15.1.0",
+      "resolved": "https://registry.npmjs.org/@sinonjs/fake-timers/-/fake-timers-15.1.0.tgz",
+      "integrity": "sha512-cqfapCxwTGsrR80FEgOoPsTonoefMBY7dnUEbQ+GRcved0jvkJLzvX6F4WtN+HBqbPX/SiFsIRUp+IrCW/2I2w==",
       "dev": true,
       "license": "BSD-3-Clause",
       "dependencies": {
-        "@sinonjs/commons": "^3.0.0"
+        "@sinonjs/commons": "^3.0.1"
       }
     },
     "node_modules/@sinonjs/samsam": {
@@ -737,13 +738,6 @@
         "node": ">=4"
       }
     },
-    "node_modules/@sinonjs/text-encoding": {
-      "version": "0.7.3",
-      "resolved": "https://registry.npmjs.org/@sinonjs/text-encoding/-/text-encoding-0.7.3.tgz",
-      "integrity": "sha512-DE427ROAphMQzU4ENbliGYrBSYPXF+TtLg9S8vzeA+OF4ZKzoDdzfL8sxuMUGS/lgRhM6j1URSk9ghf7Xo1tyA==",
-      "dev": true,
-      "license": "(Unlicense OR Apache-2.0)"
-    },
     "node_modules/@tootallnate/once": {
       "version": "1.1.2",
       "resolved": "https://registry.npmjs.org/@tootallnate/once/-/once-1.1.2.tgz",
@@ -4604,13 +4598,6 @@
         "node": ">=4.0"
       }
     },
-    "node_modules/just-extend": {
-      "version": "6.2.0",
-      "resolved": "https://registry.npmjs.org/just-extend/-/just-extend-6.2.0.tgz",
-      "integrity": "sha512-cYofQu2Xpom82S6qD778jBDpwvvy39s1l/hrYij2u9AMdQcGRpaBu6kY4mVhuno5kJVi1DAz4aiphA2WI1/OAw==",
-      "dev": true,
-      "license": "MIT"
-    },
     "node_modules/keyv": {
       "version": "4.5.4",
       "resolved": "https://registry.npmjs.org/keyv/-/keyv-4.5.4.tgz",
@@ -5026,41 +5013,6 @@
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       "license": "ISC"
     },
-    "node_modules/nise": {
-      "version": "6.1.1",
-      "resolved": "https://registry.npmjs.org/nise/-/nise-6.1.1.tgz",
-      "integrity": "sha512-aMSAzLVY7LyeM60gvBS423nBmIPP+Wy7St7hsb+8/fc1HmeoHJfLO8CKse4u3BtOZvQLJghYPI2i/1WZrEj5/g==",
-      "dev": true,
-      "license": "BSD-3-Clause",
-      "dependencies": {
-        "@sinonjs/commons": "^3.0.1",
-        "@sinonjs/fake-timers": "^13.0.1",
-        "@sinonjs/text-encoding": "^0.7.3",
-        "just-extend": "^6.2.0",
-        "path-to-regexp": "^8.1.0"
-      }
-    },
-    "node_modules/nise/node_modules/@sinonjs/fake-timers": {
-      "version": "13.0.5",
-      "resolved": "https://registry.npmjs.org/@sinonjs/fake-timers/-/fake-timers-13.0.5.tgz",
-      "integrity": "sha512-36/hTbH2uaWuGVERyC6da9YwGWnzUZXuPro/F2LfsdOsLnCojz/iSH8MxUt/FD2S5XBSVPhmArFUXcpCQ2Hkiw==",
-      "dev": true,
-      "license": "BSD-3-Clause",
-      "dependencies": {
-        "@sinonjs/commons": "^3.0.1"
-      }
-    },
-    "node_modules/nise/node_modules/path-to-regexp": {
-      "version": "8.3.0",
-      "resolved": "https://registry.npmjs.org/path-to-regexp/-/path-to-regexp-8.3.0.tgz",
-      "integrity": "sha512-7jdwVIRtsP8MYpdXSwOS0YdD0Du+qOoF/AEPIt88PcCFrZCzx41oxku1jD88hZBwbNUIEfpqvuhjFaMAqMTWnA==",
-      "dev": true,
-      "license": "MIT",
-      "funding": {
-        "type": "opencollective",
-        "url": "https://opencollective.com/express"
-      }
-    },
     "node_modules/node-fetch": {
       "version": "2.7.0",
       "resolved": "https://registry.npmjs.org/node-fetch/-/node-fetch-2.7.0.tgz",
@@ -6517,24 +6469,33 @@
       "license": "ISC"
     },
     "node_modules/sinon": {
-      "version": "18.0.1",
-      "resolved": "https://registry.npmjs.org/sinon/-/sinon-18.0.1.tgz",
-      "integrity": "sha512-a2N2TDY1uGviajJ6r4D1CyRAkzE9NNVlYOV1wX5xQDuAk0ONgzgRl0EjCQuRCPxOwp13ghsMwt9Gdldujs39qw==",
+      "version": "21.0.1",
+      "resolved": "https://registry.npmjs.org/sinon/-/sinon-21.0.1.tgz",
+      "integrity": "sha512-Z0NVCW45W8Mg5oC/27/+fCqIHFnW8kpkFOq0j9XJIev4Ld0mKmERaZv5DMLAb9fGCevjKwaEeIQz5+MBXfZcDw==",
       "dev": true,
       "license": "BSD-3-Clause",
       "dependencies": {
         "@sinonjs/commons": "^3.0.1",
-        "@sinonjs/fake-timers": "11.2.2",
-        "@sinonjs/samsam": "^8.0.0",
-        "diff": "^5.2.0",
-        "nise": "^6.0.0",
-        "supports-color": "^7"
+        "@sinonjs/fake-timers": "^15.1.0",
+        "@sinonjs/samsam": "^8.0.3",
+        "diff": "^8.0.2",
+        "supports-color": "^7.2.0"
       },
       "funding": {
         "type": "opencollective",
         "url": "https://opencollective.com/sinon"
       }
     },
+    "node_modules/sinon/node_modules/diff": {
+      "version": "8.0.3",
+      "resolved": "https://registry.npmjs.org/diff/-/diff-8.0.3.tgz",
+      "integrity": "sha512-qejHi7bcSD4hQAZE0tNAawRK1ZtafHDmMTMkrrIGgSLl7hTnQHmKCeB45xAcbfTqK2zowkM3j3bHt/4b/ARbYQ==",
+      "dev": true,
+      "license": "BSD-3-Clause",
+      "engines": {
+        "node": ">=0.3.1"
+      }
+    },
     "node_modules/sinon/node_modules/supports-color": {
       "version": "7.2.0",
       "resolved": "https://registry.npmjs.org/supports-color/-/supports-color-7.2.0.tgz",
diff --git a/package.json b/package.json
index 1d66c7a..1ee7e2a 100644
--- a/package.json
+++ b/package.json
@@ -36,7 +36,7 @@
   },
   "devDependencies": {
     "codecov": "3.8.3",
-    "sinon": "18.0.1",
+    "sinon": "21.0.1",
     "standard": "17.1.2",
     "express": "4.22.1",
     "mocha": "10.8.2",