diff --git a/backend/package-lock.json b/backend/package-lock.json
index 462d15f..e676d8d 100644
--- a/backend/package-lock.json
+++ b/backend/package-lock.json
@@ -13,7 +13,7 @@
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         "cors": "^2.8.5",
         "dotenv": "^17.4.2",
-        "express": "^4.22.1",
+        "express": "^5.2.1",
         "helmet": "^8.1.0",
         "highlight.js": "^11.11.1",
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@@ -427,18 +427,43 @@
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-        "negotiator": "0.6.3"
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-        "statuses": "~2.0.2",
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@@ -953,15 +943,16 @@
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-        "node": ">= 0.6"
+        "node": ">=18"
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+      "funding": {
+        "type": "opencollective",
+        "url": "https://opencollective.com/express"
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@@ -983,10 +974,13 @@
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-      "license": "MIT"
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+      "license": "MIT",
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-        "ms": "2.0.0"
+        "ms": "^2.1.3"
+      },
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+        "node": ">=6.0"
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+      "peerDependenciesMeta": {
+        "supports-color": {
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+        }
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@@ -1080,16 +1082,6 @@
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@@ -1251,45 +1243,67 @@
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+        "etag": "^1.8.1",
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+        "router": "^2.2.0",
+        "send": "^1.1.0",
+        "serve-static": "^2.2.0",
+        "statuses": "^2.0.1",
+        "type-is": "^2.0.1",
+        "vary": "^1.1.2"
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+      "funding": {
+        "type": "opencollective",
+        "url": "https://opencollective.com/express"
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+      "resolved": "https://registry.npmjs.org/mime-db/-/mime-db-1.54.0.tgz",
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+      "license": "MIT",
+      "engines": {
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@@ -1339,21 +1353,24 @@
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-        "statuses": "2.0.1",
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+        "debug": "^4.4.0",
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+        "url": "https://opencollective.com/express"
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@@ -1436,12 +1453,12 @@
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@@ -1655,31 +1672,39 @@
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       "license": "MIT",
       "dependencies": {
-        "safer-buffer": ">= 2.1.2 < 3"
+        "safer-buffer": ">= 2.1.2 < 3.0.0"
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+        "url": "https://opencollective.com/express"
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@@ -1779,6 +1804,12 @@
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+    "node_modules/type-is/node_modules/mime-db": {
+      "version": "1.54.0",
+      "resolved": "https://registry.npmjs.org/mime-db/-/mime-db-1.54.0.tgz",
+      "integrity": "sha512-aU5EJuIN2WDemCcAp2vFBfp/m4EAhWJnUNSSw0ixs7/kXbd6Pg64EmwJkNdFhB8aWt1sH2CTXrLxo/iAGV3oPQ==",
+      "license": "MIT",
+      "engines": {
+        "node": ">= 0.6"
+      }
+    },
+    "node_modules/type-is/node_modules/mime-types": {
+      "version": "3.0.2",
+      "resolved": "https://registry.npmjs.org/mime-types/-/mime-types-3.0.2.tgz",
+      "integrity": "sha512-Lbgzdk0h4juoQ9fCKXW4by0UJqj+nOOrI9MJ1sSj4nI8aI2eo1qmvQEie4VD1glsS250n15LsWsYtCugiStS5A==",
+      "license": "MIT",
+      "dependencies": {
+        "mime-db": "^1.54.0"
+      },
+      "engines": {
+        "node": ">=18"
+      },
+      "funding": {
+        "type": "opencollective",
+        "url": "https://opencollective.com/express"
+      }
+    },
     "node_modules/typescript": {
       "version": "6.0.2",
       "resolved": "https://registry.npmjs.org/typescript/-/typescript-6.0.2.tgz",
@@ -3031,15 +3010,6 @@
       "integrity": "sha512-EPD5q1uXyFxJpCrLnCc1nHnq3gOa6DZBocAIiI2TaSCA7VCJ1UJDMagCzIkXNsUYfD1daK//LTEQ8xiIbrHtcw==",
       "license": "MIT"
     },
-    "node_modules/utils-merge": {
-      "version": "1.0.1",
-      "resolved": "https://registry.npmjs.org/utils-merge/-/utils-merge-1.0.1.tgz",
-      "integrity": "sha512-pMZTvIkT1d+TFGvDOqodOclx0QWkkgi6Tdoa8gC8ffGAAqz9pzPTZWAybbsHHoED/ztMtkv/VoYTYyShUn81hA==",
-      "license": "MIT",
-      "engines": {
-        "node": ">= 0.4.0"
-      }
-    },
     "node_modules/vary": {
       "version": "1.1.2",
       "resolved": "https://registry.npmjs.org/vary/-/vary-1.1.2.tgz",
@@ -3165,7 +3135,6 @@
       "version": "1.0.2",
       "resolved": "https://registry.npmjs.org/wrappy/-/wrappy-1.0.2.tgz",
       "integrity": "sha512-l4Sp/DRseor9wL6EvV2+TuQn63dMkPjZ/sp9XkghTEbV9KlPS1xUsZ3u7/IQO4wxtcFB4bgpQPRcR3QCvezPcQ==",
-      "dev": true,
       "license": "ISC"
     },
     "node_modules/ws": {
diff --git a/backend/package.json b/backend/package.json
index 99aaedd..5b60a0a 100644
--- a/backend/package.json
+++ b/backend/package.json
@@ -17,7 +17,7 @@
     "axios": "^1.15.2",
     "cors": "^2.8.5",
     "dotenv": "^17.4.2",
-    "express": "^4.22.1",
+    "express": "^5.2.1",
     "helmet": "^8.1.0",
     "highlight.js": "^11.11.1",
     "lib0": "^0.2.117",