diff --git a/.travis.yml b/.travis.yml
index 04f7055..cbfc5fd 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -9,17 +9,24 @@ matrix:
     - os: osx
       osx_image: xcode10
       env: SWIFT_VERSION=4.2
+    - os: osx
+      osx_image: xcode10.2
+      env: SWIFT_VERSION=5.0
     - os: linux
       env: SWIFT_VERSION=4.0.3
     - os: linux
       env: SWIFT_VERSION=4.1
     - os: linux
       env: SWIFT_VERSION=4.2
+    - os: linux
+      env: SWIFT_VERSION=4.2.3
+    - os: linux
+      env: SWIFT_VERSION=5.0
 language: generic
 sudo: required
 dist: trusty
 install:
-  - eval "$(curl -sL https://swiftenv.fuller.li/install.sh)"
+  - if [ "$TRAVIS_OS_NAME" == "linux" ]; then eval "$(curl -sL https://swiftenv.fuller.li/install.sh)"; fi
   - if [ "$TRAVIS_OS_NAME" == "osx" ]; then wget --output-document /tmp/SwiftLint.pkg https://github.com/realm/SwiftLint/releases/download/0.27.0/SwiftLint.pkg &&
     sudo installer -pkg /tmp/SwiftLint.pkg -target /; fi
 script:
diff --git a/Package.resolved b/Package.resolved
index ff6830b..21b168b 100644
--- a/Package.resolved
+++ b/Package.resolved
@@ -6,8 +6,8 @@
         "repositoryURL": "https://github.com/kylef/PathKit.git",
         "state": {
           "branch": null,
-          "revision": "e2f5be30e4c8f531c9c1e8765aa7b71c0a45d7a0",
-          "version": "0.9.2"
+          "revision": "73f8e9dca9b7a3078cb79128217dc8f2e585a511",
+          "version": "1.0.0"
         }
       },
       {
diff --git a/Package@swift-5.swift b/Package@swift-5.swift
new file mode 100644
index 0000000..43b97ee
--- /dev/null
+++ b/Package@swift-5.swift
@@ -0,0 +1,23 @@
+// swift-tools-version:5.0
+import PackageDescription
+
+let package = Package(
+  name: "Stencil",
+  products: [
+    .library(name: "Stencil", targets: ["Stencil"])
+  ],
+  dependencies: [
+    .package(url: "https://github.com/kylef/PathKit.git", from: "1.0.0"),
+    .package(url: "https://github.com/kylef/Spectre.git", from: "0.9.0")
+  ],
+  targets: [
+    .target(name: "Stencil", dependencies: [
+      "PathKit"
+    ], path: "Sources"),
+    .testTarget(name: "StencilTests", dependencies: [
+      "Stencil",
+      "Spectre"
+    ])
+  ],
+  swiftLanguageVersions: [.v4, .v4_2, .v5]
+)
diff --git a/Sources/Node.swift b/Sources/Node.swift
index d06d3ca..3386211 100644
--- a/Sources/Node.swift
+++ b/Sources/Node.swift
@@ -71,7 +71,7 @@ public class VariableNode: NodeType {
 
     if hasToken("if", at: 1) {
       let components = components.suffix(from: 2)
-      if let elseIndex = components.index(of: "else") {
+      if let elseIndex = components.firstIndex(of: "else") {
         condition = try parser.compileExpression(components: Array(components.prefix(upTo: elseIndex)), token: token)
         let elseToken = components.suffix(from: elseIndex.advanced(by: 1)).joined(separator: " ")
         elseExpression = try parser.compileResolvable(elseToken, containedIn: token)
diff --git a/Sources/_SwiftSupport.swift b/Sources/_SwiftSupport.swift
index 2441350..4519fbd 100644
--- a/Sources/_SwiftSupport.swift
+++ b/Sources/_SwiftSupport.swift
@@ -36,3 +36,11 @@ public extension Variable {
   }
 }
 #endif
+
+#if !swift(>=4.2)
+extension ArraySlice where Element: Equatable {
+    func firstIndex(of element: Element) -> Int? {
+        return index(of: element)
+    }
+}
+#endif
diff --git a/Stencil.podspec.json b/Stencil.podspec.json
index e667dc4..fbac048 100644
--- a/Stencil.podspec.json
+++ b/Stencil.podspec.json
@@ -24,7 +24,7 @@
     "tvos": "9.0"
   },
   "cocoapods_version": ">= 1.4.0",
-  "swift_version": "4.2",
+  "swift_version": "5.0",
   "requires_arc": true,
   "dependencies": {
     "PathKit": [
diff --git a/Tests/StencilTests/EnvironmentSpec.swift b/Tests/StencilTests/EnvironmentSpec.swift
index f1bf469..f5b829f 100644
--- a/Tests/StencilTests/EnvironmentSpec.swift
+++ b/Tests/StencilTests/EnvironmentSpec.swift
@@ -215,7 +215,7 @@ final class EnvironmentIncludeTemplateTests: XCTestCase {
   override func setUp() {
     super.setUp()
 
-    let path = Path(#file) + ".." + "fixtures"
+    let path = Path(#file as String) + ".." + "fixtures"
     let loader = FileSystemLoader(paths: [path])
     environment = Environment(loader: loader)
     template = ""
@@ -291,7 +291,7 @@ final class EnvironmentBaseAndChildTemplateTests: XCTestCase {
   override func setUp() {
     super.setUp()
 
-    let path = Path(#file) + ".." + "fixtures"
+    let path = Path(#file as String) + ".." + "fixtures"
     let loader = FileSystemLoader(paths: [path])
     environment = Environment(loader: loader)
     childTemplate = ""
diff --git a/Tests/StencilTests/IncludeSpec.swift b/Tests/StencilTests/IncludeSpec.swift
index d7d1ddf..4743a94 100644
--- a/Tests/StencilTests/IncludeSpec.swift
+++ b/Tests/StencilTests/IncludeSpec.swift
@@ -4,7 +4,7 @@ import Spectre
 import XCTest
 
 final class IncludeTests: XCTestCase {
-  let path = Path(#file) + ".." + "fixtures"
+  let path = Path(#file as String) + ".." + "fixtures"
   lazy var loader = FileSystemLoader(paths: [path])
   lazy var environment = Environment(loader: loader)
 
diff --git a/Tests/StencilTests/InheritanceSpec.swift b/Tests/StencilTests/InheritanceSpec.swift
index c71736a..4f91aff 100644
--- a/Tests/StencilTests/InheritanceSpec.swift
+++ b/Tests/StencilTests/InheritanceSpec.swift
@@ -4,7 +4,7 @@ import Stencil
 import XCTest
 
 final class InheritanceTests: XCTestCase {
-  let path = Path(#file) + ".." + "fixtures"
+  let path = Path(#file as String) + ".." + "fixtures"
   lazy var loader = FileSystemLoader(paths: [path])
   lazy var environment = Environment(loader: loader)
 
diff --git a/Tests/StencilTests/LexerSpec.swift b/Tests/StencilTests/LexerSpec.swift
index 9a5e880..adf6a92 100644
--- a/Tests/StencilTests/LexerSpec.swift
+++ b/Tests/StencilTests/LexerSpec.swift
@@ -117,7 +117,7 @@ final class LexerTests: XCTestCase {
   }
 
   func testPerformance() throws {
-    let path = Path(#file) + ".."  + "fixtures" + "huge.html"
+    let path = Path(#file as String) + ".."  + "fixtures" + "huge.html"
     let content: String = try path.read()
 
     measure {
diff --git a/Tests/StencilTests/LoaderSpec.swift b/Tests/StencilTests/LoaderSpec.swift
index 00a1f43..3cd189b 100644
--- a/Tests/StencilTests/LoaderSpec.swift
+++ b/Tests/StencilTests/LoaderSpec.swift
@@ -5,7 +5,7 @@ import XCTest
 
 final class TemplateLoaderTests: XCTestCase {
   func testFileSystemLoader() {
-    let path = Path(#file) + ".."  + "fixtures"
+    let path = Path(#file as String) + ".." + "fixtures"
     let loader = FileSystemLoader(paths: [path])
     let environment = Environment(loader: loader)