diff --git a/BUILD b/BUILD
index 6e1c9ac..a09a155 100644
--- a/BUILD
+++ b/BUILD
@@ -126,8 +126,10 @@ swift_library(
     srcs = glob([
         "Tests/PromisesPerformanceTests/*.swift",
     ]),
-    copts = SWIFT_COPTS,
-    swift_version = 4,
+    copts = SWIFT_COPTS + [
+        "-swift-version",
+        "4",
+    ],
     deps = [
         ":FBLPromisesTestHelpers",
         ":PromisesTestHelpers",
diff --git a/WORKSPACE b/WORKSPACE
index 03d0808..e37a3a3 100644
--- a/WORKSPACE
+++ b/WORKSPACE
@@ -1,17 +1,17 @@
 git_repository(
     name = "bazel_skylib",
     remote = "https://github.com/bazelbuild/bazel-skylib.git",
-    tag = "0.2.0",
+    tag = "0.3.1",
 )
 
 git_repository(
     name = "build_bazel_rules_apple",
     remote = "https://github.com/bazelbuild/rules_apple.git",
-    tag = "0.3.0",
+    tag = "0.5.0",
 )
 
 http_file(
     name = "xctestrunner",
     executable = 1,
-    url = "https://github.com/google/xctestrunner/releases/download/0.2.1/ios_test_runner.par",
+    url = "https://github.com/google/xctestrunner/releases/download/0.2.2/ios_test_runner.par",
 )