diff --git a/Nimble.xcodeproj/project.pbxproj b/Nimble.xcodeproj/project.pbxproj
index 42df18a0c..33beed068 100644
--- a/Nimble.xcodeproj/project.pbxproj
+++ b/Nimble.xcodeproj/project.pbxproj
@@ -1841,7 +1841,7 @@
 				GCC_WARN_UNUSED_FUNCTION = YES;
 				GCC_WARN_UNUSED_VARIABLE = YES;
 				IPHONEOS_DEPLOYMENT_TARGET = 8.0;
-				MACOSX_DEPLOYMENT_TARGET = 10.9;
+				MACOSX_DEPLOYMENT_TARGET = 10.10;
 				METAL_ENABLE_DEBUG_INFO = YES;
 				ONLY_ACTIVE_ARCH = YES;
 				SDKROOT = iphoneos;
@@ -1899,7 +1899,7 @@
 				GCC_WARN_UNUSED_FUNCTION = YES;
 				GCC_WARN_UNUSED_VARIABLE = YES;
 				IPHONEOS_DEPLOYMENT_TARGET = 8.0;
-				MACOSX_DEPLOYMENT_TARGET = 10.9;
+				MACOSX_DEPLOYMENT_TARGET = 10.10;
 				METAL_ENABLE_DEBUG_INFO = NO;
 				SDKROOT = iphoneos;
 				SWIFT_OPTIMIZATION_LEVEL = "-Owholemodule";
diff --git a/Sources/Nimble/Adapters/NimbleEnvironment.swift b/Sources/Nimble/Adapters/NimbleEnvironment.swift
index e1b543236..0bd13ebcb 100644
--- a/Sources/Nimble/Adapters/NimbleEnvironment.swift
+++ b/Sources/Nimble/Adapters/NimbleEnvironment.swift
@@ -30,13 +30,7 @@ internal class NimbleEnvironment {
     var awaiter: Awaiter
 
     init() {
-        let timeoutQueue: DispatchQueue
-        if #available(OSX 10.10, *) {
-            timeoutQueue = DispatchQueue.global(qos: .userInitiated)
-        } else {
-            timeoutQueue = DispatchQueue.global(priority: .high)
-        }
-
+        let timeoutQueue = DispatchQueue.global(qos: .userInitiated)
         awaiter = Awaiter(
             waitLock: AssertionWaitLock(),
             asyncQueue: .main,
diff --git a/Tests/NimbleTests/AsynchronousTest.swift b/Tests/NimbleTests/AsynchronousTest.swift
index c983f1505..5a48e0a2b 100644
--- a/Tests/NimbleTests/AsynchronousTest.swift
+++ b/Tests/NimbleTests/AsynchronousTest.swift
@@ -51,20 +51,12 @@ final class AsyncTest: XCTestCase, XCTestCaseProvider {
 
         var asyncOperation: () -> Void = { sleepThenSetValueTo(1) }
 
-        if #available(OSX 10.10, *) {
-            DispatchQueue.global().async(execute: asyncOperation)
-        } else {
-            DispatchQueue.global(priority: .default).async(execute: asyncOperation)
-        }
+        DispatchQueue.global().async(execute: asyncOperation)
         expect { value }.toEventually(equal(1))
 
         asyncOperation = { sleepThenSetValueTo(0) }
 
-        if #available(OSX 10.10, *) {
-            DispatchQueue.global().async(execute: asyncOperation)
-        } else {
-            DispatchQueue.global(priority: .default).async(execute: asyncOperation)
-        }
+        DispatchQueue.global().async(execute: asyncOperation)
         expect { value }.toEventuallyNot(equal(1))
     }
 
@@ -105,11 +97,7 @@ final class AsyncTest: XCTestCase, XCTestCaseProvider {
                     done()
                     waiting = false
                 }
-                if #available(OSX 10.10, *) {
-                    DispatchQueue.global().async(execute: asyncOperation)
-                } else {
-                    DispatchQueue.global(priority: .default).async(execute: asyncOperation)
-                }
+                DispatchQueue.global().async(execute: asyncOperation)
             }
         }
 
@@ -185,11 +173,7 @@ final class AsyncTest: XCTestCase, XCTestCaseProvider {
             }.to(raiseException(named: "InvalidNimbleAPIUsage"))
             executedAsyncBlock = true
         }
-        if #available(OSX 10.10, *) {
-            DispatchQueue.global().async(execute: asyncOperation)
-        } else {
-            DispatchQueue.global(priority: .default).async(execute: asyncOperation)
-        }
+        DispatchQueue.global().async(execute: asyncOperation)
         expect(executedAsyncBlock).toEventually(beTruthy())
 #endif
     }
@@ -203,11 +187,7 @@ final class AsyncTest: XCTestCase, XCTestCaseProvider {
             }.to(raiseException(named: "InvalidNimbleAPIUsage"))
             executedAsyncBlock = true
         }
-        if #available(OSX 10.10, *) {
-            DispatchQueue.global().async(execute: asyncOperation)
-        } else {
-            DispatchQueue.global(priority: .default).async(execute: asyncOperation)
-        }
+        DispatchQueue.global().async(execute: asyncOperation)
         expect(executedAsyncBlock).toEventually(beTruthy())
 #endif
     }