diff --git a/Package.swift b/Package.swift
index cce17d9..eb01a30 100644
--- a/Package.swift
+++ b/Package.swift
@@ -1,9 +1,13 @@
-// swift-tools-version:4.0
-// The swift-tools-version declares the minimum version of Swift required to build this package.
+// swift-tools-version:5.1
 
 import PackageDescription
 let package = Package(
     name: "Sica",
+    platforms: [
+        .iOS(.v9),
+        .macOS(.v10_10),
+        .tvOS(.v10)
+    ],
     products: [
         .library(
             name: "Sica",
@@ -14,5 +18,6 @@ let package = Package(
             name: "Sica",
             dependencies: [],
             path: "Sica/Source")
-    ]
+    ],
+    swiftLanguageVersions: [.v4_2, .v5]
 )
diff --git a/README.md b/README.md
index 7ad3331..b409850 100644
--- a/README.md
+++ b/README.md
@@ -64,7 +64,7 @@ pod 'Sica'
 Sica is available through `SwiftPM`, create ` Package.swift` and add `dependencies` value
 ```Package.swift
 dependencies: [
-    .package(url: "https://github.com/cats-oss/Sica.git", from: "0.4.0")
+    .package(url: "https://github.com/cats-oss/Sica.git", from: "0.4.1")
 ]
 ```
 See also: [GitHub - j-channings/swift-package-manager-ios: Example of how to use SPM v4 to manage iOS dependencies](https://github.com/j-channings/swift-package-manager-ios)
diff --git a/Sica.podspec b/Sica.podspec
index 415e25c..abf8e36 100644
--- a/Sica.podspec
+++ b/Sica.podspec
@@ -8,7 +8,7 @@
 
 Pod::Spec.new do |s|
   s.name         = "Sica"
-  s.version      = "0.4.0"
+  s.version      = "0.4.1"
   s.summary      = "Sica can execute various animations sequentially or parallely"
   s.homepage     = "https://github.com/cats-oss/Sica"
   s.license      = { :type => "MIT", :file => "LICENSE" }
diff --git a/Sica/Source/CALayer+Sica.swift b/Sica/Source/CALayer+Sica.swift
index 39f0b3e..03d0c53 100644
--- a/Sica/Source/CALayer+Sica.swift
+++ b/Sica/Source/CALayer+Sica.swift
@@ -7,6 +7,7 @@
 //
 
 import Foundation
+import QuartzCore
 
 private let _animatorAssociatedKey = UnsafeMutablePointer<UInt>.allocate(capacity: 1)
 
diff --git a/Sica/Source/FillMode.swift b/Sica/Source/FillMode.swift
index 3d6469e..282f702 100644
--- a/Sica/Source/FillMode.swift
+++ b/Sica/Source/FillMode.swift
@@ -7,6 +7,7 @@
 //
 
 import Foundation
+import QuartzCore
 
 public struct FillMode {
     #if swift(>=4.2)