diff --git a/JSONAPI.playground/Pages/Usage.xcplaygroundpage/Contents.swift b/JSONAPI.playground/Pages/Usage.xcplaygroundpage/Contents.swift
index 25b0235..cdd90fe 100644
--- a/JSONAPI.playground/Pages/Usage.xcplaygroundpage/Contents.swift
+++ b/JSONAPI.playground/Pages/Usage.xcplaygroundpage/Contents.swift
@@ -49,11 +49,15 @@ print("-----")
 
 // MARK: - Pass successfully parsed body to other parts of the code
 
+/*
+ ---- CRASHING IN XCODE 10.2 PLAYGROUND ----
+
 if case let .data(bodyData) = peopleResponse.body {
 	print("first person's name: \(bodyData.primary.values[0][\.fullName])")
 } else {
 	print("no body data")
 }
+ */
 
 // MARK: - Work in the abstract
 
diff --git a/JSONAPI.playground/contents.xcplayground b/JSONAPI.playground/contents.xcplayground
index e240eff..3da156e 100644
--- a/JSONAPI.playground/contents.xcplayground
+++ b/JSONAPI.playground/contents.xcplayground
@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
-<playground version='6.0' target-platform='macos' executeOnSourceChanges='false'>
+<playground version='6.0' target-platform='macos'>
     <pages>
         <page name='Test Library'/>
         <page name='Usage'/>
diff --git a/JSONAPI.podspec b/JSONAPI.podspec
index fe4dd9a..a87f919 100644
--- a/JSONAPI.podspec
+++ b/JSONAPI.podspec
@@ -16,7 +16,7 @@ Pod::Spec.new do |spec|
   #
 
   spec.name         = "JSONAPI"
-  spec.version      = "0.19.0"
+  spec.version      = "0.20.0"
   spec.summary      = "Swift Codable JSON API framework."
 
   # This description is used to generate tags and improve search results.
@@ -132,10 +132,10 @@ See the JSON API Spec here: https://jsonapi.org/format/
   #  where they will only apply to your library. If you depend on other Podspecs
   #  you can include multiple dependencies to ensure it works.
 
-  spec.swift_version = "4.2"
+  spec.swift_version = "5.0"
   # spec.requires_arc = true
 
   # spec.xcconfig = { "HEADER_SEARCH_PATHS" => "$(SDKROOT)/usr/include/libxml2" }
-  spec.dependency "Poly", "~> 1.1"
+  spec.dependency "Poly", "~> 2.0"
 
 end
diff --git a/Package.resolved b/Package.resolved
index 920f7b5..fac7812 100644
--- a/Package.resolved
+++ b/Package.resolved
@@ -6,8 +6,8 @@
         "repositoryURL": "https://github.com/mattpolzin/Poly.git",
         "state": {
           "branch": null,
-          "revision": "77f45b8963a51c02d71fc4075eba5cff47ff0d07",
-          "version": "1.0.0"
+          "revision": "d24d4c1214dd05f89eb1182a46592856dd0a0645",
+          "version": "2.0.0"
         }
       }
     ]
diff --git a/Package.swift b/Package.swift
index 8f0d1b8..0789b25 100644
--- a/Package.swift
+++ b/Package.swift
@@ -1,10 +1,14 @@
-// swift-tools-version:4.2
+// swift-tools-version:5.0
 // The swift-tools-version declares the minimum version of Swift required to build this package.
 
 import PackageDescription
 
 let package = Package(
     name: "JSONAPI",
+    platforms: [
+      .macOS(.v10_10),
+      .iOS(.v10)
+    ],
     products: [
         .library(
             name: "JSONAPI",
@@ -14,7 +18,7 @@ let package = Package(
 			targets: ["JSONAPITesting"])
     ],
     dependencies: [
-		.package(url: "https://github.com/mattpolzin/Poly.git", from: "1.0.0"),
+		.package(url: "https://github.com/mattpolzin/Poly.git", from: "2.0.0"),
     ],
     targets: [
         .target(
@@ -30,5 +34,5 @@ let package = Package(
             name: "JSONAPITestingTests",
             dependencies: ["JSONAPI", "JSONAPITesting"])
     ],
-  	swiftLanguageVersions: [.v4_2]
+  	swiftLanguageVersions: [.v5]
 )
diff --git a/Sources/JSONAPI/Result.swift b/Sources/JSONAPI/Result.swift
deleted file mode 100644
index 326bdcc..0000000
--- a/Sources/JSONAPI/Result.swift
+++ /dev/null
@@ -1,45 +0,0 @@
-//
-//  Result.swift
-//  JSONAPI
-//
-//  Created by Mathew Polzin on 12/5/18.
-//
-
-enum Result<T, E: Swift.Error> {
-	case success(T)
-	case failure(E)
-
-	var value: T? {
-		guard case .success(let val) = self else {
-			return nil
-		}
-		return val
-	}
-
-	var error: E? {
-		guard case .failure(let err) = self else {
-			return nil
-		}
-		return err
-	}
-
-	func map<U>(_ transform: (T) -> U) -> Result<U, E> {
-		switch self {
-		case .failure(let err):
-			return .failure(err)
-		case .success(let val):
-			return .success(transform(val))
-		}
-	}
-}
-
-extension Result: CustomStringConvertible where T: CustomStringConvertible, E: CustomStringConvertible {
-	var description: String {
-		switch self {
-		case .success(let val):
-			return String(describing: val)
-		case .failure(let err):
-			return String(describing: err)
-		}
-	}
-}
diff --git a/Tests/JSONAPITests/Poly/PolyProxyTests.swift b/Tests/JSONAPITests/Poly/PolyProxyTests.swift
index 01dcfb6..a294f4e 100644
--- a/Tests/JSONAPITests/Poly/PolyProxyTests.swift
+++ b/Tests/JSONAPITests/Poly/PolyProxyTests.swift
@@ -86,10 +86,10 @@ public extension PolyProxyTests {
 		public typealias Relationships = NoRelationships
 	}
 
-	public typealias UserA = BasicEntity<UserDescription1>
-	public typealias UserB = BasicEntity<UserDescription2>
+	typealias UserA = BasicEntity<UserDescription1>
+	typealias UserB = BasicEntity<UserDescription2>
 
-	public typealias User = Poly2<UserA, UserB>
+	typealias User = Poly2<UserA, UserB>
 }
 
 extension Poly2: EntityProxy, JSONTyped where A == PolyProxyTests.UserA, B == PolyProxyTests.UserB {