diff --git a/src/Aardvark.Base/Introspection/Introspection.cs b/src/Aardvark.Base/Introspection/Introspection.cs
index 25e64d30..e94d80ca 100644
--- a/src/Aardvark.Base/Introspection/Introspection.cs
+++ b/src/Aardvark.Base/Introspection/Introspection.cs
@@ -2073,8 +2073,12 @@ private static string ArchitectureString(Architecture arch)
             }
         }
 
+        private static bool isInitialized = false;
+
         public static void Init()
         {
+            if (isInitialized) return;
+
             Report.BeginTimed("initializing aardvark");
 
             Report.Begin("System Information:");
@@ -2188,6 +2192,8 @@ public static void Init()
             }
 
             Report.End();
+
+            isInitialized = true;
         }
 
         private static void LoadAll(IEnumerable<Assembly> xs)
diff --git a/src/Tests/Aardvark.Base.FSharp.Tests/Tensors/TensorTests.fs b/src/Tests/Aardvark.Base.FSharp.Tests/Tensors/TensorTests.fs
index 51e10175..2d8147b3 100644
--- a/src/Tests/Aardvark.Base.FSharp.Tests/Tensors/TensorTests.fs
+++ b/src/Tests/Aardvark.Base.FSharp.Tests/Tensors/TensorTests.fs
@@ -209,8 +209,8 @@ module ``Tensor Tests`` =
         let data = [| 42; 32; 108; -34 |]
         let info = Tensor4Info(V4l(2, 2, 1, 1), V4l(1, 2, 4, 4))
 
-        pinned data (fun ptr ->
-            let nv = NativeTensor4.ofNativeInt<int> info ptr
+        data |> NativePtr.pinArr (fun ptr ->
+            let nv = NativeTensor4<int>(ptr, info)
 
             let mutable index = 0
             nv |> NativeTensor4.iterPtr (fun coord ptr ->
@@ -226,10 +226,10 @@ module ``Tensor Tests`` =
         let dstArray = [| 0L; 0L; 0L; 0L |]
         let info = Tensor4Info(V4l(2, 2, 1, 1), V4l(2, 1, 4, 4))
 
-        pinned srcArray (fun srcPtr ->
-            pinned dstArray (fun dstPtr ->
-                let src = NativeTensor4<int>(NativePtr.ofNativeInt srcPtr, info)
-                let dst = NativeTensor4<int64>(NativePtr.ofNativeInt dstPtr, info)
+        srcArray |> NativePtr.pinArr (fun srcPtr ->
+            dstArray |> NativePtr.pinArr (fun dstPtr ->
+                let src = NativeTensor4<int>(srcPtr, info)
+                let dst = NativeTensor4<int64>(dstPtr, info)
 
                 (src, dst) ||> NativeTensor4.iterPtr2 (fun coord src dst ->
                     let value = NativePtr.read src