diff --git a/.idea/.gitignore b/.idea/.gitignore
new file mode 100644
index 0000000..b58b603
--- /dev/null
+++ b/.idea/.gitignore
@@ -0,0 +1,5 @@
+# Default ignored files
+/shelf/
+/workspace.xml
+# Editor-based HTTP Client requests
+/httpRequests/
diff --git a/.idea/misc.xml b/.idea/misc.xml
new file mode 100644
index 0000000..0548b67
--- /dev/null
+++ b/.idea/misc.xml
@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="MaterialThemeProjectNewConfig">
+    <option name="metadata">
+      <MTProjectMetadataState>
+        <option name="userId" value="-62fe7e2d:19874553008:-7ffa" />
+      </MTProjectMetadataState>
+    </option>
+  </component>
+</project>
\ No newline at end of file
diff --git a/.idea/modules.xml b/.idea/modules.xml
new file mode 100644
index 0000000..aac95b1
--- /dev/null
+++ b/.idea/modules.xml
@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="ProjectModuleManager">
+    <modules>
+      <module fileurl="file://$PROJECT_DIR$/.idea/p256k1.mleku.dev.iml" filepath="$PROJECT_DIR$/.idea/p256k1.mleku.dev.iml" />
+    </modules>
+  </component>
+</project>
\ No newline at end of file
diff --git a/.idea/p256k1.mleku.dev.iml b/.idea/p256k1.mleku.dev.iml
new file mode 100644
index 0000000..24643cc
--- /dev/null
+++ b/.idea/p256k1.mleku.dev.iml
@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<module type="WEB_MODULE" version="4">
+  <component name="NewModuleRootManager">
+    <content url="file://$MODULE_DIR$">
+      <excludeFolder url="file://$MODULE_DIR$/.tmp" />
+      <excludeFolder url="file://$MODULE_DIR$/temp" />
+      <excludeFolder url="file://$MODULE_DIR$/tmp" />
+    </content>
+    <orderEntry type="inheritedJdk" />
+    <orderEntry type="sourceFolder" forTests="false" />
+  </component>
+</module>
\ No newline at end of file
diff --git a/.idea/vcs.xml b/.idea/vcs.xml
new file mode 100644
index 0000000..35eb1dd
--- /dev/null
+++ b/.idea/vcs.xml
@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="VcsDirectoryMappings">
+    <mapping directory="" vcs="Git" />
+  </component>
+</project>
\ No newline at end of file
diff --git a/ecdh.go b/ecdh.go
index 245d72a..6143a60 100644
--- a/ecdh.go
+++ b/ecdh.go
@@ -204,9 +204,10 @@ func ECDH(output []byte, pubkey *PublicKey, seckey []byte, hashfp ECDHHashFuncti
 		return errors.New("secret key cannot be zero")
 	}
 	
-	// Compute res = s * pt using constant-time multiplication
+	// Compute res = s * pt using optimized windowed multiplication (variable-time)
+	// ECDH doesn't require constant-time since the secret key is already known
 	var res GroupElementJacobian
-	EcmultConst(&res, &pt, &s)
+	ecmultWindowedVar(&res, &pt, &s)
 	
 	// Convert to affine
 	var resAff GroupElementAffine
@@ -352,9 +353,10 @@ func ECDHXOnly(output []byte, pubkey *PublicKey, seckey []byte) error {
 		return errors.New("secret key cannot be zero")
 	}
 	
-	// Compute res = s * pt
+	// Compute res = s * pt using optimized windowed multiplication (variable-time)
+	// ECDH doesn't require constant-time since the secret key is already known
 	var res GroupElementJacobian
-	EcmultConst(&res, &pt, &s)
+	ecmultWindowedVar(&res, &pt, &s)
 	
 	// Convert to affine
 	var resAff GroupElementAffine