diff --git a/cli/package-lock.json b/cli/package-lock.json
index 9fdd7df..531af18 100644
--- a/cli/package-lock.json
+++ b/cli/package-lock.json
@@ -12,7 +12,7 @@
         "understand-quickly": "bin/understand-quickly.mjs"
       },
       "engines": {
-        "node": ">=20.0.0"
+        "node": ">=18.0.0"
       }
     }
   }
diff --git a/cli/package.json b/cli/package.json
index 7f72081..940c31a 100644
--- a/cli/package.json
+++ b/cli/package.json
@@ -13,7 +13,7 @@
     "LICENSE"
   ],
   "engines": {
-    "node": ">=20.0.0"
+    "node": ">=18.0.0"
   },
   "scripts": {
     "test": "node --test 'tests/*.test.mjs'"
diff --git a/mcp/package-lock.json b/mcp/package-lock.json
index e3adc0b..77bebdd 100644
--- a/mcp/package-lock.json
+++ b/mcp/package-lock.json
@@ -16,12 +16,12 @@
         "understand-quickly-mcp": "dist/index.js"
       },
       "devDependencies": {
-        "@types/node": "^20.19.39",
+        "@types/node": "^18.19.0",
         "tsx": "^4.19.0",
         "typescript": "^5.5.0"
       },
       "engines": {
-        "node": ">=20"
+        "node": ">=18.0.0"
       }
     },
     "node_modules/@esbuild/aix-ppc64": {
@@ -519,13 +519,13 @@
       }
     },
     "node_modules/@types/node": {
-      "version": "20.19.39",
-      "resolved": "https://registry.npmjs.org/@types/node/-/node-20.19.39.tgz",
-      "integrity": "sha512-orrrD74MBUyK8jOAD/r0+lfa1I2MO6I+vAkmAWzMYbCcgrN4lCrmK52gRFQq/JRxfYPfonkr4b0jcY7Olqdqbw==",
+      "version": "18.19.130",
+      "resolved": "https://registry.npmjs.org/@types/node/-/node-18.19.130.tgz",
+      "integrity": "sha512-GRaXQx6jGfL8sKfaIDD6OupbIHBr9jv7Jnaml9tB7l4v068PAOXqfcujMMo5PhbIs6ggR1XODELqahT2R8v0fg==",
       "dev": true,
       "license": "MIT",
       "dependencies": {
-        "undici-types": "~6.21.0"
+        "undici-types": "~5.26.4"
       }
     },
     "node_modules/accepts": {
@@ -1657,9 +1657,9 @@
       }
     },
     "node_modules/undici-types": {
-      "version": "6.21.0",
-      "resolved": "https://registry.npmjs.org/undici-types/-/undici-types-6.21.0.tgz",
-      "integrity": "sha512-iwDZqg0QAGrg9Rav5H4n0M64c3mkR59cJ6wQp+7C4nI0gsmExaedaYLNO44eT4AtBBwjbTiGPMlt2Md0T9H9JQ==",
+      "version": "5.26.5",
+      "resolved": "https://registry.npmjs.org/undici-types/-/undici-types-5.26.5.tgz",
+      "integrity": "sha512-JlCMO+ehdEIKqlFxk6IfVoAUVmgz7cU7zD/h9XZ0qzeosSHmUJVOzSQvvYSYWXkFXC+IfLKSIffhv0sVZup6pA==",
       "dev": true,
       "license": "MIT"
     },
diff --git a/mcp/package.json b/mcp/package.json
index 69d6f0e..2d5a8a5 100644
--- a/mcp/package.json
+++ b/mcp/package.json
@@ -15,7 +15,7 @@
   },
   "type": "module",
   "engines": {
-    "node": ">=20"
+    "node": ">=18.0.0"
   },
   "main": "dist/index.js",
   "bin": {
@@ -32,7 +32,7 @@
     "zod": "^4.4.0"
   },
   "devDependencies": {
-    "@types/node": "^20.19.39",
+    "@types/node": "^18.19.0",
     "tsx": "^4.19.0",
     "typescript": "^5.5.0"
   }
diff --git a/package-lock.json b/package-lock.json
index e56f6df..1acf90a 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -15,7 +15,7 @@
         "c8": "^11.0.0"
       },
       "engines": {
-        "node": ">=20.0.0"
+        "node": ">=18.0.0"
       }
     },
     "node_modules/@bcoe/v8-coverage": {
diff --git a/package.json b/package.json
index ebab29e..1aab6de 100644
--- a/package.json
+++ b/package.json
@@ -17,7 +17,7 @@
     "url": "https://github.com/looptech-ai/understand-quickly/issues"
   },
   "type": "module",
-  "engines": { "node": ">=20.0.0" },
+  "engines": { "node": ">=18.0.0" },
   "scripts": {
     "validate": "node scripts/validate.mjs",
     "sync": "node scripts/sync.mjs",