diff --git a/.eslintrc.json b/.eslintrc.json
index 02244542..ee4a471c 100644
--- a/.eslintrc.json
+++ b/.eslintrc.json
@@ -8,7 +8,8 @@
         "google"
     ],
     "parserOptions": {
-        "ecmaVersion": "latest"
+        "ecmaVersion": "latest",
+        "sourceType": "module"
     },
     "rules": {
         "array-bracket-spacing": "error",
diff --git a/package-lock.json b/package-lock.json
index 8c82aece..34f43958 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -6,7 +6,7 @@
     "": {
       "devDependencies": {
         "browserify": "^17.0.1",
-        "chai": "^4.3.6",
+        "chai": "^5.3.1",
         "eslint": "^8.20.0",
         "eslint-config-google": "^0.14.0",
         "mocha": "^11.7.1",
@@ -1185,12 +1185,12 @@
       }
     },
     "node_modules/assertion-error": {
-      "version": "1.1.0",
-      "resolved": "https://registry.npmjs.org/assertion-error/-/assertion-error-1.1.0.tgz",
-      "integrity": "sha512-jgsaNduz+ndvGyFt3uSuWqvy4lCnIJiovtouQN5JZHOKCS2QuhEdbcQHFhVksz2N2U9hXJo8odG7ETyWlEeuDw==",
+      "version": "2.0.1",
+      "resolved": "https://registry.npmjs.org/assertion-error/-/assertion-error-2.0.1.tgz",
+      "integrity": "sha512-Izi8RQcffqCeNVgFigKli1ssklIbpHnCYc6AknXGYoB6grJqyeby7jv12JUQgmTAnIDnbck1uxksT4dzN3PWBA==",
       "dev": true,
       "engines": {
-        "node": "*"
+        "node": ">=12"
       }
     },
     "node_modules/available-typed-arrays": {
@@ -1630,21 +1630,19 @@
       "license": "CC-BY-4.0"
     },
     "node_modules/chai": {
-      "version": "4.3.7",
-      "resolved": "https://registry.npmjs.org/chai/-/chai-4.3.7.tgz",
-      "integrity": "sha512-HLnAzZ2iupm25PlN0xFreAlBA5zaBSv3og0DdeGA4Ar6h6rJ3A0rolRUKJhSF2V10GZKDgWF/VmAEsNWjCRB+A==",
+      "version": "5.3.1",
+      "resolved": "https://registry.npmjs.org/chai/-/chai-5.3.1.tgz",
+      "integrity": "sha512-48af6xm9gQK8rhIcOxWwdGzIervm8BVTin+yRp9HEvU20BtVZ2lBywlIJBzwaDtvo0FvjeL7QdCADoUoqIbV3A==",
       "dev": true,
       "dependencies": {
-        "assertion-error": "^1.1.0",
-        "check-error": "^1.0.2",
-        "deep-eql": "^4.1.2",
-        "get-func-name": "^2.0.0",
-        "loupe": "^2.3.1",
-        "pathval": "^1.1.1",
-        "type-detect": "^4.0.5"
+        "assertion-error": "^2.0.1",
+        "check-error": "^2.1.1",
+        "deep-eql": "^5.0.1",
+        "loupe": "^3.1.0",
+        "pathval": "^2.0.0"
       },
       "engines": {
-        "node": ">=4"
+        "node": ">=18"
       }
     },
     "node_modules/chalk": {
@@ -1664,12 +1662,12 @@
       }
     },
     "node_modules/check-error": {
-      "version": "1.0.2",
-      "resolved": "https://registry.npmjs.org/check-error/-/check-error-1.0.2.tgz",
-      "integrity": "sha512-BrgHpW9NURQgzoNyjfq0Wu6VFO6D7IZEmJNdtgNqpzGG8RuNFHt2jQxWlAs4HMe119chBnv+34syEZtc6IhLtA==",
+      "version": "2.1.1",
+      "resolved": "https://registry.npmjs.org/check-error/-/check-error-2.1.1.tgz",
+      "integrity": "sha512-OAlb+T7V4Op9OwdkjmguYRqncdlx5JiofwOAUkmTF+jNdHwzTaTs4sRAGpzLF3oOz5xAyDGrPgeIDFQmDOTiJw==",
       "dev": true,
       "engines": {
-        "node": "*"
+        "node": ">= 16"
       }
     },
     "node_modules/chokidar": {
@@ -1930,13 +1928,10 @@
       }
     },
     "node_modules/deep-eql": {
-      "version": "4.1.3",
-      "resolved": "https://registry.npmjs.org/deep-eql/-/deep-eql-4.1.3.tgz",
-      "integrity": "sha512-WaEtAOpRA1MQ0eohqZjpGD8zdI0Ovsm8mmFhaDN8dvDZzyoUMcYDnf5Y6iu7HTXxf8JDS23qWa4a+hKCDyOPzw==",
+      "version": "5.0.2",
+      "resolved": "https://registry.npmjs.org/deep-eql/-/deep-eql-5.0.2.tgz",
+      "integrity": "sha512-h5k/5U50IJJFpzfL6nO9jaaumfjO/f2NjK/oYB2Djzm4p9L+3T9qWpZqZ2hAbLPuuYq9wrU08WQyBTL5GbPk5Q==",
       "dev": true,
-      "dependencies": {
-        "type-detect": "^4.0.0"
-      },
       "engines": {
         "node": ">=6"
       }
@@ -2643,15 +2638,6 @@
         "node": "6.* || 8.* || >= 10.*"
       }
     },
-    "node_modules/get-func-name": {
-      "version": "2.0.0",
-      "resolved": "https://registry.npmjs.org/get-func-name/-/get-func-name-2.0.0.tgz",
-      "integrity": "sha512-Hm0ixYtaSZ/V7C8FJrtZIuBBI+iSgL+1Aq82zSu8VQNB4S3Gk8e7Qs3VwBDJAhmRZcFqkl3tQu36g/Foh5I5ig==",
-      "dev": true,
-      "engines": {
-        "node": "*"
-      }
-    },
     "node_modules/get-intrinsic": {
       "version": "1.3.0",
       "resolved": "https://registry.npmjs.org/get-intrinsic/-/get-intrinsic-1.3.0.tgz",
@@ -3572,13 +3558,10 @@
       }
     },
     "node_modules/loupe": {
-      "version": "2.3.6",
-      "resolved": "https://registry.npmjs.org/loupe/-/loupe-2.3.6.tgz",
-      "integrity": "sha512-RaPMZKiMy8/JruncMU5Bt6na1eftNoo++R4Y+N2FrxkDVTrGvcyzFTsaGif4QTeKESheMGegbhw6iUAq+5A8zA==",
-      "dev": true,
-      "dependencies": {
-        "get-func-name": "^2.0.0"
-      }
+      "version": "3.2.0",
+      "resolved": "https://registry.npmjs.org/loupe/-/loupe-3.2.0.tgz",
+      "integrity": "sha512-2NCfZcT5VGVNX9mSZIxLRkEAegDGBpuQZBy13desuHeVORmBDyAET4TkJr4SjqQy3A8JDofMN6LpkK8Xcm/dlw==",
+      "dev": true
     },
     "node_modules/lru-cache": {
       "version": "5.1.1",
@@ -4391,12 +4374,12 @@
       "license": "ISC"
     },
     "node_modules/pathval": {
-      "version": "1.1.1",
-      "resolved": "https://registry.npmjs.org/pathval/-/pathval-1.1.1.tgz",
-      "integrity": "sha512-Dp6zGqpTdETdR63lehJYPeIOqpiNBNtc7BpWSLrOje7UaIsE5aY92r/AunQA7rsXvet3lrJ3JnZX29UPTKXyKQ==",
+      "version": "2.0.1",
+      "resolved": "https://registry.npmjs.org/pathval/-/pathval-2.0.1.tgz",
+      "integrity": "sha512-//nshmD55c46FuFw26xV/xFAaB5HF9Xdap7HJBBnrKdAd6/GxDBaNA1870O79+9ueg61cZLSVc+OaFlfmObYVQ==",
       "dev": true,
       "engines": {
-        "node": "*"
+        "node": ">= 14.16"
       }
     },
     "node_modules/pbkdf2": {
@@ -6490,9 +6473,9 @@
       }
     },
     "assertion-error": {
-      "version": "1.1.0",
-      "resolved": "https://registry.npmjs.org/assertion-error/-/assertion-error-1.1.0.tgz",
-      "integrity": "sha512-jgsaNduz+ndvGyFt3uSuWqvy4lCnIJiovtouQN5JZHOKCS2QuhEdbcQHFhVksz2N2U9hXJo8odG7ETyWlEeuDw==",
+      "version": "2.0.1",
+      "resolved": "https://registry.npmjs.org/assertion-error/-/assertion-error-2.0.1.tgz",
+      "integrity": "sha512-Izi8RQcffqCeNVgFigKli1ssklIbpHnCYc6AknXGYoB6grJqyeby7jv12JUQgmTAnIDnbck1uxksT4dzN3PWBA==",
       "dev": true
     },
     "available-typed-arrays": {
@@ -6828,18 +6811,16 @@
       "dev": true
     },
     "chai": {
-      "version": "4.3.7",
-      "resolved": "https://registry.npmjs.org/chai/-/chai-4.3.7.tgz",
-      "integrity": "sha512-HLnAzZ2iupm25PlN0xFreAlBA5zaBSv3og0DdeGA4Ar6h6rJ3A0rolRUKJhSF2V10GZKDgWF/VmAEsNWjCRB+A==",
+      "version": "5.3.1",
+      "resolved": "https://registry.npmjs.org/chai/-/chai-5.3.1.tgz",
+      "integrity": "sha512-48af6xm9gQK8rhIcOxWwdGzIervm8BVTin+yRp9HEvU20BtVZ2lBywlIJBzwaDtvo0FvjeL7QdCADoUoqIbV3A==",
       "dev": true,
       "requires": {
-        "assertion-error": "^1.1.0",
-        "check-error": "^1.0.2",
-        "deep-eql": "^4.1.2",
-        "get-func-name": "^2.0.0",
-        "loupe": "^2.3.1",
-        "pathval": "^1.1.1",
-        "type-detect": "^4.0.5"
+        "assertion-error": "^2.0.1",
+        "check-error": "^2.1.1",
+        "deep-eql": "^5.0.1",
+        "loupe": "^3.1.0",
+        "pathval": "^2.0.0"
       }
     },
     "chalk": {
@@ -6853,9 +6834,9 @@
       }
     },
     "check-error": {
-      "version": "1.0.2",
-      "resolved": "https://registry.npmjs.org/check-error/-/check-error-1.0.2.tgz",
-      "integrity": "sha512-BrgHpW9NURQgzoNyjfq0Wu6VFO6D7IZEmJNdtgNqpzGG8RuNFHt2jQxWlAs4HMe119chBnv+34syEZtc6IhLtA==",
+      "version": "2.1.1",
+      "resolved": "https://registry.npmjs.org/check-error/-/check-error-2.1.1.tgz",
+      "integrity": "sha512-OAlb+T7V4Op9OwdkjmguYRqncdlx5JiofwOAUkmTF+jNdHwzTaTs4sRAGpzLF3oOz5xAyDGrPgeIDFQmDOTiJw==",
       "dev": true
     },
     "chokidar": {
@@ -7072,13 +7053,10 @@
       "dev": true
     },
     "deep-eql": {
-      "version": "4.1.3",
-      "resolved": "https://registry.npmjs.org/deep-eql/-/deep-eql-4.1.3.tgz",
-      "integrity": "sha512-WaEtAOpRA1MQ0eohqZjpGD8zdI0Ovsm8mmFhaDN8dvDZzyoUMcYDnf5Y6iu7HTXxf8JDS23qWa4a+hKCDyOPzw==",
-      "dev": true,
-      "requires": {
-        "type-detect": "^4.0.0"
-      }
+      "version": "5.0.2",
+      "resolved": "https://registry.npmjs.org/deep-eql/-/deep-eql-5.0.2.tgz",
+      "integrity": "sha512-h5k/5U50IJJFpzfL6nO9jaaumfjO/f2NjK/oYB2Djzm4p9L+3T9qWpZqZ2hAbLPuuYq9wrU08WQyBTL5GbPk5Q==",
+      "dev": true
     },
     "deep-is": {
       "version": "0.1.4",
@@ -7598,12 +7576,6 @@
       "integrity": "sha512-DyFP3BM/3YHTQOCUL/w0OZHR0lpKeGrxotcHWcqNEdnltqFwXVfhEBQ94eIo34AfQpo0rGki4cyIiftY06h2Fg==",
       "dev": true
     },
-    "get-func-name": {
-      "version": "2.0.0",
-      "resolved": "https://registry.npmjs.org/get-func-name/-/get-func-name-2.0.0.tgz",
-      "integrity": "sha512-Hm0ixYtaSZ/V7C8FJrtZIuBBI+iSgL+1Aq82zSu8VQNB4S3Gk8e7Qs3VwBDJAhmRZcFqkl3tQu36g/Foh5I5ig==",
-      "dev": true
-    },
     "get-intrinsic": {
       "version": "1.3.0",
       "resolved": "https://registry.npmjs.org/get-intrinsic/-/get-intrinsic-1.3.0.tgz",
@@ -8266,13 +8238,10 @@
       }
     },
     "loupe": {
-      "version": "2.3.6",
-      "resolved": "https://registry.npmjs.org/loupe/-/loupe-2.3.6.tgz",
-      "integrity": "sha512-RaPMZKiMy8/JruncMU5Bt6na1eftNoo++R4Y+N2FrxkDVTrGvcyzFTsaGif4QTeKESheMGegbhw6iUAq+5A8zA==",
-      "dev": true,
-      "requires": {
-        "get-func-name": "^2.0.0"
-      }
+      "version": "3.2.0",
+      "resolved": "https://registry.npmjs.org/loupe/-/loupe-3.2.0.tgz",
+      "integrity": "sha512-2NCfZcT5VGVNX9mSZIxLRkEAegDGBpuQZBy13desuHeVORmBDyAET4TkJr4SjqQy3A8JDofMN6LpkK8Xcm/dlw==",
+      "dev": true
     },
     "lru-cache": {
       "version": "5.1.1",
@@ -8904,9 +8873,9 @@
       }
     },
     "pathval": {
-      "version": "1.1.1",
-      "resolved": "https://registry.npmjs.org/pathval/-/pathval-1.1.1.tgz",
-      "integrity": "sha512-Dp6zGqpTdETdR63lehJYPeIOqpiNBNtc7BpWSLrOje7UaIsE5aY92r/AunQA7rsXvet3lrJ3JnZX29UPTKXyKQ==",
+      "version": "2.0.1",
+      "resolved": "https://registry.npmjs.org/pathval/-/pathval-2.0.1.tgz",
+      "integrity": "sha512-//nshmD55c46FuFw26xV/xFAaB5HF9Xdap7HJBBnrKdAd6/GxDBaNA1870O79+9ueg61cZLSVc+OaFlfmObYVQ==",
       "dev": true
     },
     "pbkdf2": {
diff --git a/package.json b/package.json
index 5ea7073e..0005ce3d 100644
--- a/package.json
+++ b/package.json
@@ -9,7 +9,7 @@
   },
   "devDependencies": {
     "browserify": "^17.0.1",
-    "chai": "^4.3.6",
+    "chai": "^5.3.1",
     "eslint": "^8.20.0",
     "eslint-config-google": "^0.14.0",
     "mocha": "^11.7.1",
@@ -17,5 +17,6 @@
     "nyc": "^17.1.0",
     "sass": "^1.90.0",
     "sinon": "^21.0.0"
-  }
+  },
+  "type": "module"
 }
diff --git a/testing/unittest.js b/testing/unittest.js
index dc17ecc0..64e987bc 100644
--- a/testing/unittest.js
+++ b/testing/unittest.js
@@ -1,9 +1,9 @@
-const { expect } = require('chai')
-const sinon = require('sinon')
-const { doInitFilter, doFilter } = require('../src/pytest_html/scripts/filter.js')
-const { doInitSort, doSort } = require('../src/pytest_html/scripts/sort.js')
-const dataModule = require('../src/pytest_html/scripts/datamanager.js')
-const storageModule = require('../src/pytest_html/scripts/storage.js')
+import { expect } from 'chai'
+import sinon from 'sinon'
+import { doInitFilter, doFilter } from '../src/pytest_html/scripts/filter.js'
+import { doInitSort, doSort } from '../src/pytest_html/scripts/sort.js'
+import * as dataModule from '../src/pytest_html/scripts/datamanager.js'
+import * as storageModule from '../src/pytest_html/scripts/storage.js'
 
 
 const setTestData = () => {