diff --git a/.npmrc b/.npmrc
index a2b5a7ee2..1dec0082b 100644
--- a/.npmrc
+++ b/.npmrc
@@ -1,2 +1,3 @@
 registry=https://registry.npmjs.org
 scope=permaweb
+engine-strict = true
diff --git a/connect/package-lock.json b/connect/package-lock.json
index fb225fdfa..765914f4d 100644
--- a/connect/package-lock.json
+++ b/connect/package-lock.json
@@ -23,7 +23,8 @@
         "typescript": "^5.4.2"
       },
       "engines": {
-        "node": ">=18"
+        "node": ">=18",
+        "yarn": "please-use-npm"
       }
     },
     "node_modules/@esbuild/aix-ppc64": {
diff --git a/connect/package.json b/connect/package.json
index 86cd3e4df..95a3ca1e4 100644
--- a/connect/package.json
+++ b/connect/package.json
@@ -58,6 +58,7 @@
     "typescript": "^5.4.2"
   },
   "engines": {
-    "node": ">=18"
+    "node": ">=18",
+    "yarn": "please-use-npm"
   }
 }
diff --git a/package.json b/package.json
index e88467177..780c1157f 100644
--- a/package.json
+++ b/package.json
@@ -16,6 +16,9 @@
     "sort-package-json": "^2.10.0",
     "standard": "^17.1.0"
   },
+  "engines": {
+    "yarn": "please-use-npm"
+  },
   "standard": {
     "ignore": [
       "dist",
diff --git a/scheduler-utils/package-lock.json b/scheduler-utils/package-lock.json
index f8af928bf..eec59a9dc 100644
--- a/scheduler-utils/package-lock.json
+++ b/scheduler-utils/package-lock.json
@@ -17,7 +17,8 @@
         "typescript": "^5.4.5"
       },
       "engines": {
-        "node": ">=18"
+        "node": ">=18",
+        "yarn": "please-use-npm"
       }
     },
     "node_modules/@esbuild/aix-ppc64": {
diff --git a/scheduler-utils/package.json b/scheduler-utils/package.json
index ae4235b86..d02935b36 100644
--- a/scheduler-utils/package.json
+++ b/scheduler-utils/package.json
@@ -40,6 +40,7 @@
     "typescript": "^5.4.5"
   },
   "engines": {
-    "node": ">=18"
+    "node": ">=18",
+    "yarn": "please-use-npm"
   }
 }
diff --git a/servers/cu/package-lock.json b/servers/cu/package-lock.json
index c315fb03a..9941a4eea 100644
--- a/servers/cu/package-lock.json
+++ b/servers/cu/package-lock.json
@@ -35,7 +35,8 @@
         "nodemon": "^3.1.0"
       },
       "engines": {
-        "node": ">=18"
+        "node": ">=18",
+        "yarn": "please-use-npm"
       }
     },
     "node_modules/@fastify/ajv-compiler": {
diff --git a/servers/cu/package.json b/servers/cu/package.json
index f1c38bbcc..4a2ec9186 100644
--- a/servers/cu/package.json
+++ b/servers/cu/package.json
@@ -38,6 +38,7 @@
     "nodemon": "^3.1.0"
   },
   "engines": {
-    "node": ">=18"
+    "node": ">=18",
+    "yarn": "please-use-npm"
   }
 }
diff --git a/servers/mu/package-lock.json b/servers/mu/package-lock.json
index a180e823a..85659c297 100644
--- a/servers/mu/package-lock.json
+++ b/servers/mu/package-lock.json
@@ -33,7 +33,8 @@
         "supertest": "^6.3.3"
       },
       "engines": {
-        "node": "22"
+        "node": "22",
+        "yarn": "please-use-npm"
       }
     },
     "node_modules/@ethersproject/abstract-provider": {
diff --git a/servers/mu/package.json b/servers/mu/package.json
index a4a03a5f6..6d67111bd 100644
--- a/servers/mu/package.json
+++ b/servers/mu/package.json
@@ -43,6 +43,7 @@
     "supertest": "^6.3.3"
   },
   "engines": {
-    "node": "22"
+    "node": "22",
+    "yarn": "please-use-npm"
   }
 }
diff --git a/servers/ur/package-lock.json b/servers/ur/package-lock.json
index 6351cf08c..ff6f35c84 100644
--- a/servers/ur/package-lock.json
+++ b/servers/ur/package-lock.json
@@ -22,7 +22,8 @@
         "nodemon": "^3.0.2"
       },
       "engines": {
-        "node": ">=18"
+        "node": ">=18",
+        "yarn": "please-use-npm"
       }
     },
     "node_modules/@ethersproject/abstract-provider": {
diff --git a/servers/ur/package.json b/servers/ur/package.json
index 1538d25dc..8a390540a 100644
--- a/servers/ur/package.json
+++ b/servers/ur/package.json
@@ -24,6 +24,7 @@
     "nodemon": "^3.0.2"
   },
   "engines": {
-    "node": ">=18"
+    "node": ">=18",
+    "yarn": "please-use-npm"
   }
 }