diff --git a/Source/ConstraintMaker.swift b/Source/ConstraintMaker.swift
index 49e03d2..d68bc9b 100644
--- a/Source/ConstraintMaker.swift
+++ b/Source/ConstraintMaker.swift
@@ -61,13 +61,13 @@ public class ConstraintMaker {
         return constraint
     }
     
-    internal class func prepareConstraints(view: View, block: (make: ConstraintMaker) -> Void) -> Array<Constraint> {
+    internal class func prepareConstraints(view: View, @noescape block: (make: ConstraintMaker) -> Void) -> Array<Constraint> {
         let maker = ConstraintMaker(view: view)
         block(make: maker)
         return maker.constraints
     }
     
-    internal class func makeConstraints(view: View, block: (make: ConstraintMaker) -> Void) {
+    internal class func makeConstraints(view: View, @noescape block: (make: ConstraintMaker) -> Void) {
         #if os(iOS)
         view.setTranslatesAutoresizingMaskIntoConstraints(false)
         #else
@@ -80,7 +80,7 @@ public class ConstraintMaker {
         }
     }
     
-    internal class func remakeConstraints(view: View, block: (make: ConstraintMaker) -> Void) {
+    internal class func remakeConstraints(view: View, @noescape block: (make: ConstraintMaker) -> Void) {
         #if os(iOS)
         view.setTranslatesAutoresizingMaskIntoConstraints(false)
         #else
@@ -99,7 +99,7 @@ public class ConstraintMaker {
         }
     }
     
-    internal class func updateConstraints(view: View, block: (make: ConstraintMaker) -> Void) {
+    internal class func updateConstraints(view: View, @noescape block: (make: ConstraintMaker) -> Void) {
         #if os(iOS)
         view.setTranslatesAutoresizingMaskIntoConstraints(false)
         #else
diff --git a/Source/View+Snap.swift b/Source/View+Snap.swift
index 09d1bab..3d7ae28 100644
--- a/Source/View+Snap.swift
+++ b/Source/View+Snap.swift
@@ -68,19 +68,19 @@ public extension View {
     public var snp_centerWithinMargins: ConstraintItem { return ConstraintItem(object: self, attributes: ConstraintAttributes.CenterWithinMargins) }
     #endif
     
-    public func snp_prepareConstraints(block: (make: ConstraintMaker) -> Void) -> Array<Constraint> {
+    public func snp_prepareConstraints(@noescape block: (make: ConstraintMaker) -> Void) -> Array<Constraint> {
         return ConstraintMaker.prepareConstraints(self, block: block)
     }
     
-    public func snp_makeConstraints(block: (make: ConstraintMaker) -> Void) {
+    public func snp_makeConstraints(@noescape block: (make: ConstraintMaker) -> Void) {
         ConstraintMaker.makeConstraints(self, block: block)
     }
     
-    public func snp_updateConstraints(block: (make: ConstraintMaker) -> Void) {
+    public func snp_updateConstraints(@noescape block: (make: ConstraintMaker) -> Void) {
         ConstraintMaker.updateConstraints(self, block: block)
     }
     
-    public func snp_remakeConstraints(block: (make: ConstraintMaker) -> Void) {
+    public func snp_remakeConstraints(@noescape block: (make: ConstraintMaker) -> Void) {
         ConstraintMaker.remakeConstraints(self, block: block)
     }