diff --git a/Metaballs.xcodeproj/project.pbxproj b/Metaballs.xcodeproj/project.pbxproj
index d2805fd..dee73da 100644
--- a/Metaballs.xcodeproj/project.pbxproj
+++ b/Metaballs.xcodeproj/project.pbxproj
@@ -11,6 +11,8 @@
 		C0B906D51F45432700B5F89B /* Preferences.swift in Sources */ = {isa = PBXBuildFile; fileRef = C0B906D41F45432700B5F89B /* Preferences.swift */; };
 		C0B906DE1F455AD000B5F89B /* MetaballsSaverView.h in Headers */ = {isa = PBXBuildFile; fileRef = C0B906DD1F455AD000B5F89B /* MetaballsSaverView.h */; };
 		C0B906E01F455AD000B5F89B /* MetaballsSaverView.m in Sources */ = {isa = PBXBuildFile; fileRef = C0B906DF1F455AD000B5F89B /* MetaballsSaverView.m */; };
+		C0B906E51F455B7C00B5F89B /* Renderer.swift in Sources */ = {isa = PBXBuildFile; fileRef = C0BBE3AB1F2E941200E68524 /* Renderer.swift */; };
+		C0B906E61F455B7E00B5F89B /* Shaders.metal in Sources */ = {isa = PBXBuildFile; fileRef = C0BBE3A91F2E91D900E68524 /* Shaders.metal */; };
 		C0BBE36B1F2E816500E68524 /* AppDelegate.swift in Sources */ = {isa = PBXBuildFile; fileRef = C0BBE36A1F2E816500E68524 /* AppDelegate.swift */; };
 		C0BBE36D1F2E816500E68524 /* ViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = C0BBE36C1F2E816500E68524 /* ViewController.swift */; };
 		C0BBE36F1F2E816500E68524 /* Assets.xcassets in Resources */ = {isa = PBXBuildFile; fileRef = C0BBE36E1F2E816500E68524 /* Assets.xcassets */; };
@@ -22,8 +24,6 @@
 		C0BBE3A41F2E81C700E68524 /* Metaballs.swift in Sources */ = {isa = PBXBuildFile; fileRef = C0BBE3A31F2E81C700E68524 /* Metaballs.swift */; };
 		C0BBE3A51F2E87D500E68524 /* MetaballsKit.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = C0BBE38C1F2E81B600E68524 /* MetaballsKit.framework */; };
 		C0BBE3A81F2E893A00E68524 /* MetalKit.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = C0BBE3A71F2E893A00E68524 /* MetalKit.framework */; };
-		C0BBE3AA1F2E91D900E68524 /* Shaders.metal in Sources */ = {isa = PBXBuildFile; fileRef = C0BBE3A91F2E91D900E68524 /* Shaders.metal */; };
-		C0BBE3AC1F2E941200E68524 /* Renderer.swift in Sources */ = {isa = PBXBuildFile; fileRef = C0BBE3AB1F2E941200E68524 /* Renderer.swift */; };
 		C0BBE3AD1F30CD7E00E68524 /* MetalKit.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = C0BBE3A71F2E893A00E68524 /* MetalKit.framework */; };
 		C0CE7C001F362C3F001516B6 /* Geometry.swift in Sources */ = {isa = PBXBuildFile; fileRef = C0CE7BFF1F362C3F001516B6 /* Geometry.swift */; };
 		C0DF1D791F3789DC0038B0A0 /* Memory.swift in Sources */ = {isa = PBXBuildFile; fileRef = C0DF1D781F3789DC0038B0A0 /* Memory.swift */; };
@@ -159,8 +159,6 @@
 			children = (
 				C0BBE36A1F2E816500E68524 /* AppDelegate.swift */,
 				C0BBE36C1F2E816500E68524 /* ViewController.swift */,
-				C0BBE3AB1F2E941200E68524 /* Renderer.swift */,
-				C0BBE3A91F2E91D900E68524 /* Shaders.metal */,
 				C0BBE36E1F2E816500E68524 /* Assets.xcassets */,
 				C0BBE3701F2E816500E68524 /* Main.storyboard */,
 				C0BBE3731F2E816500E68524 /* Info.plist */,
@@ -185,6 +183,8 @@
 				C0BBE3A31F2E81C700E68524 /* Metaballs.swift */,
 				C0CE7BFF1F362C3F001516B6 /* Geometry.swift */,
 				C0DF1D781F3789DC0038B0A0 /* Memory.swift */,
+				C0BBE3AB1F2E941200E68524 /* Renderer.swift */,
+				C0BBE3A91F2E91D900E68524 /* Shaders.metal */,
 				C0B906D41F45432700B5F89B /* Preferences.swift */,
 				C091616F1F3F5AE6009C4263 /* PreferencesViewController.swift */,
 			);
@@ -433,8 +433,6 @@
 			isa = PBXSourcesBuildPhase;
 			buildActionMask = 2147483647;
 			files = (
-				C0BBE3AC1F2E941200E68524 /* Renderer.swift in Sources */,
-				C0BBE3AA1F2E91D900E68524 /* Shaders.metal in Sources */,
 				C0BBE36D1F2E816500E68524 /* ViewController.swift in Sources */,
 				C0BBE36B1F2E816500E68524 /* AppDelegate.swift in Sources */,
 			);
@@ -453,9 +451,11 @@
 			buildActionMask = 2147483647;
 			files = (
 				C0DF1D791F3789DC0038B0A0 /* Memory.swift in Sources */,
+				C0B906E61F455B7E00B5F89B /* Shaders.metal in Sources */,
 				C0B906D51F45432700B5F89B /* Preferences.swift in Sources */,
 				C0BBE3A41F2E81C700E68524 /* Metaballs.swift in Sources */,
 				C0CE7C001F362C3F001516B6 /* Geometry.swift in Sources */,
+				C0B906E51F455B7C00B5F89B /* Renderer.swift in Sources */,
 				C09161701F3F5AE6009C4263 /* PreferencesViewController.swift in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
diff --git a/Metaballs/Renderer.swift b/MetaballsKit/Renderer.swift
similarity index 92%
rename from Metaballs/Renderer.swift
rename to MetaballsKit/Renderer.swift
index 05b892e..edc7684 100644
--- a/Metaballs/Renderer.swift
+++ b/MetaballsKit/Renderer.swift
@@ -7,37 +7,31 @@
 //
 
 import Foundation
-import MetaballsKit
 import MetalKit
 
-enum RendererError: Error {
+public enum RendererError: Error {
     case MetalError(String)
 }
 
-protocol RendererDelegate {
+public protocol RendererDelegate {
     var renderSize: Size { get set }
     var field: Field { get }
     var metalView: MTKView { get }
 }
 
-struct Point {
-    let x: Float
-    let y: Float
-}
-
 struct Vertex {
     let position: Point
     let textureCoordinate: Point
 }
 
-class Renderer: NSObject, MTKViewDelegate {
+public class Renderer: NSObject, MTKViewDelegate {
     var delegate: RendererDelegate
 
     private var device: MTLDevice
     private var commandQueue: MTLCommandQueue
     private var renderPipelineState: MTLRenderPipelineState
 
-    init(delegate: RendererDelegate) throws {
+    public init(delegate: RendererDelegate) throws {
         self.delegate = delegate
 
         guard let device = MTLCreateSystemDefaultDevice() else {
@@ -78,11 +72,11 @@ class Renderer: NSObject, MTKViewDelegate {
 
     /// MARK: - MTKViewDelegate
 
-    func mtkView(_ view: MTKView, drawableSizeWillChange size: CGSize) {
+    public func mtkView(_ view: MTKView, drawableSizeWillChange size: CGSize) {
         delegate.renderSize = Size(size: size)
     }
 
-    func draw(in view: MTKView) {
+    public func draw(in view: MTKView) {
         let field = delegate.field
 
         // Two triangles, plus texture coordinates.
diff --git a/Metaballs/Shaders.metal b/MetaballsKit/Shaders.metal
similarity index 100%
rename from Metaballs/Shaders.metal
rename to MetaballsKit/Shaders.metal