diff --git a/package-lock.json b/package-lock.json
index 8621573..24d1b5d 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -26,7 +26,7 @@
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         "@typescript-eslint/parser": "^5.62.0",
         "c8": "^9.1.0",
-        "chai": "^5.1.1",
+        "chai": "^4.4.1",
         "conventional-changelog-conventionalcommits": "^8.0.0",
         "eslint": "^8.57.0",
         "eslint-config-iplayer": "^9.2.0",
@@ -2909,12 +2909,12 @@
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-      "resolved": "https://registry.npmjs.org/assertion-error/-/assertion-error-2.0.1.tgz",
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+      "resolved": "https://registry.npmjs.org/assertion-error/-/assertion-error-1.1.0.tgz",
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       "dev": true,
       "engines": {
-        "node": ">=12"
+        "node": "*"
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     "node_modules/asynciterator.prototype": {
@@ -3088,19 +3088,21 @@
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-      "resolved": "https://registry.npmjs.org/chai/-/chai-5.1.1.tgz",
-      "integrity": "sha512-pT1ZgP8rPNqUgieVaEY+ryQr6Q4HXNg8Ei9UnLUrjN4IA7dvQC5JB+/kxVcPNDHyBcc/26CXPkbNzq3qwrOEKA==",
+      "version": "4.4.1",
+      "resolved": "https://registry.npmjs.org/chai/-/chai-4.4.1.tgz",
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       "dev": true,
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-        "assertion-error": "^2.0.1",
-        "check-error": "^2.1.1",
-        "deep-eql": "^5.0.1",
-        "loupe": "^3.1.0",
-        "pathval": "^2.0.0"
+        "assertion-error": "^1.1.0",
+        "check-error": "^1.0.3",
+        "deep-eql": "^4.1.3",
+        "get-func-name": "^2.0.2",
+        "loupe": "^2.3.6",
+        "pathval": "^1.1.1",
+        "type-detect": "^4.0.8"
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-        "node": ">=12"
+        "node": ">=4"
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     "node_modules/chalk": {
@@ -3129,12 +3131,15 @@
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-      "resolved": "https://registry.npmjs.org/check-error/-/check-error-2.1.1.tgz",
-      "integrity": "sha512-OAlb+T7V4Op9OwdkjmguYRqncdlx5JiofwOAUkmTF+jNdHwzTaTs4sRAGpzLF3oOz5xAyDGrPgeIDFQmDOTiJw==",
+      "version": "1.0.3",
+      "resolved": "https://registry.npmjs.org/check-error/-/check-error-1.0.3.tgz",
+      "integrity": "sha512-iKEoDYaRmd1mxM90a2OEfWhjsjPpYPuQ+lMYsoxB126+t8fw7ySEO48nmDg5COTjxDI65/Y2OWpeEHk3ZOe8zg==",
       "dev": true,
+      "dependencies": {
+        "get-func-name": "^2.0.2"
+      },
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-        "node": ">= 16"
+        "node": "*"
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     "node_modules/chokidar": {
@@ -3470,10 +3475,13 @@
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-      "resolved": "https://registry.npmjs.org/deep-eql/-/deep-eql-5.0.2.tgz",
-      "integrity": "sha512-h5k/5U50IJJFpzfL6nO9jaaumfjO/f2NjK/oYB2Djzm4p9L+3T9qWpZqZ2hAbLPuuYq9wrU08WQyBTL5GbPk5Q==",
+      "version": "4.1.4",
+      "resolved": "https://registry.npmjs.org/deep-eql/-/deep-eql-4.1.4.tgz",
+      "integrity": "sha512-SUwdGfqdKOwxCPeVYjwSyRpJ7Z+fhpwIAtmCUdZIWZ/YP5R9WAsyuSgpLVDi9bjWoN2LXHNss/dk3urXtdQxGg==",
       "dev": true,
+      "dependencies": {
+        "type-detect": "^4.0.0"
+      },
       "engines": {
         "node": ">=6"
       }
@@ -5797,9 +5805,9 @@
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-      "version": "3.1.1",
-      "resolved": "https://registry.npmjs.org/loupe/-/loupe-3.1.1.tgz",
-      "integrity": "sha512-edNu/8D5MKVfGVFRhFf8aAxiTM6Wumfz5XsaatSxlD3w4R1d/WEKUTydCdPGbl9K7QG/Ca3GnDV2sIKIpXRQcw==",
+      "version": "2.3.7",
+      "resolved": "https://registry.npmjs.org/loupe/-/loupe-2.3.7.tgz",
+      "integrity": "sha512-zSMINGVYkdpYSOBmLi0D1Uo7JU9nVdQKrHxC8eYlV+9YKK9WePqAlL7lSlorG/U2Fw1w0hTBmaa/jrQ3UbPHtA==",
       "dev": true,
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@@ -9323,12 +9331,12 @@
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-      "resolved": "https://registry.npmjs.org/pathval/-/pathval-2.0.0.tgz",
-      "integrity": "sha512-vE7JKRyES09KiunauX7nd2Q9/L7lhok4smP9RZTDeD4MVs72Dp2qNFVz39Nz5a0FVEW0BJR6C0DYrq6unoziZA==",
+      "version": "1.1.1",
+      "resolved": "https://registry.npmjs.org/pathval/-/pathval-1.1.1.tgz",
+      "integrity": "sha512-Dp6zGqpTdETdR63lehJYPeIOqpiNBNtc7BpWSLrOje7UaIsE5aY92r/AunQA7rsXvet3lrJ3JnZX29UPTKXyKQ==",
       "dev": true,
       "engines": {
-        "node": ">= 14.16"
+        "node": "*"
       }
     },
     "node_modules/picomatch": {
diff --git a/package.json b/package.json
index 1c646c4..7b09e5f 100644
--- a/package.json
+++ b/package.json
@@ -139,7 +139,7 @@
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     "@typescript-eslint/eslint-plugin": "^5.62.0",
     "@typescript-eslint/parser": "^5.62.0",
-    "chai": "^5.1.1",
+    "chai": "^4.4.1",
     "conventional-changelog-conventionalcommits": "^8.0.0",
     "eslint": "^8.57.0",
     "eslint-config-iplayer": "^9.2.0",