diff --git a/src/embed_tests/TestRuntime.cs b/src/embed_tests/TestRuntime.cs
index ac1fa1ac0..25b70fac5 100644
--- a/src/embed_tests/TestRuntime.cs
+++ b/src/embed_tests/TestRuntime.cs
@@ -1,6 +1,7 @@
 using System;
 using NUnit.Framework;
 using Python.Runtime;
+using Python.Runtime.Platform;
 
 namespace Python.EmbeddingTest
 {
@@ -26,10 +27,10 @@ public static void PlatformCache()
         {
             Runtime.Runtime.Initialize();
 
-            Assert.That(Runtime.Runtime.Machine, Is.Not.EqualTo(Runtime.Runtime.MachineType.Other));
+            Assert.That(Runtime.Runtime.Machine, Is.Not.EqualTo(MachineType.Other));
             Assert.That(!string.IsNullOrEmpty(Runtime.Runtime.MachineName));
 
-            Assert.That(Runtime.Runtime.OperatingSystem, Is.Not.EqualTo(Runtime.Runtime.OperatingSystemType.Other));
+            Assert.That(Runtime.Runtime.OperatingSystem, Is.Not.EqualTo(OperatingSystemType.Other));
             Assert.That(!string.IsNullOrEmpty(Runtime.Runtime.OperatingSystemName));
 
             // Don't shut down the runtime: if the python engine was initialized
@@ -39,7 +40,7 @@ public static void PlatformCache()
         [Test]
         public static void Py_IsInitializedValue()
         {
-            Runtime.Runtime.Py_Finalize(); 
+            Runtime.Runtime.Py_Finalize();
             Assert.AreEqual(0, Runtime.Runtime.Py_IsInitialized());
             Runtime.Runtime.Py_Initialize();
             Assert.AreEqual(1, Runtime.Runtime.Py_IsInitialized());
diff --git a/src/runtime/Python.Runtime.csproj b/src/runtime/Python.Runtime.csproj
index 19f776c77..c4d63695f 100644
--- a/src/runtime/Python.Runtime.csproj
+++ b/src/runtime/Python.Runtime.csproj
@@ -140,6 +140,8 @@
     <Compile Include="typemanager.cs" />
     <Compile Include="typemethod.cs" />
     <Compile Include="Util.cs" />
+    <Compile Include="platform\Types.cs" />
+    <Compile Include="platform\LibraryLoader.cs" />
   </ItemGroup>
   <ItemGroup Condition=" '$(PythonInteropFile)' != '' ">
     <Compile Include="$(PythonInteropFile)" />
diff --git a/src/runtime/platform/LibraryLoader.cs b/src/runtime/platform/LibraryLoader.cs
new file mode 100644
index 000000000..a6d88cd19
--- /dev/null
+++ b/src/runtime/platform/LibraryLoader.cs
@@ -0,0 +1,208 @@
+using System;
+using System.ComponentModel;
+using System.Runtime.InteropServices;
+
+namespace Python.Runtime.Platform
+{
+    interface ILibraryLoader
+    {
+        IntPtr Load(string dllToLoad);
+
+        IntPtr GetFunction(IntPtr hModule, string procedureName);
+
+        void Free(IntPtr hModule);
+    }
+
+    static class LibraryLoader
+    {
+        public static ILibraryLoader Get(OperatingSystemType os)
+        {
+            switch (os)
+            {
+                case OperatingSystemType.Windows:
+                    return new WindowsLoader();
+                case OperatingSystemType.Darwin:
+                    return new DarwinLoader();
+                case OperatingSystemType.Linux:
+                    return new LinuxLoader();
+                default:
+                    throw new PlatformNotSupportedException($"This operating system ({os}) is not supported");
+            }
+        }
+    }
+
+    class LinuxLoader : ILibraryLoader
+    {
+        private static int RTLD_NOW = 0x2;
+        private static int RTLD_GLOBAL = 0x100;
+        private static IntPtr RTLD_DEFAULT = IntPtr.Zero;
+        private const string NativeDll = "libdl.so";
+
+        public IntPtr Load(string dllToLoad)
+        {
+            var filename = $"lib{dllToLoad}.so";
+            ClearError();
+            var res = dlopen(filename, RTLD_NOW | RTLD_GLOBAL);
+            if (res == IntPtr.Zero)
+            {
+                var err = GetError();
+                throw new DllNotFoundException($"Could not load {filename} with flags RTLD_NOW | RTLD_GLOBAL: {err}");
+            }
+
+            return res;
+        }
+
+        public void Free(IntPtr handle)
+        {
+            dlclose(handle);
+        }
+
+        public IntPtr GetFunction(IntPtr dllHandle, string name)
+        {
+            // look in the exe if dllHandle is NULL
+            if (dllHandle == IntPtr.Zero)
+            {
+                dllHandle = RTLD_DEFAULT;
+            }
+
+            ClearError();
+            IntPtr res = dlsym(dllHandle, name);
+            if (res == IntPtr.Zero)
+            {
+                var err = GetError();
+                throw new MissingMethodException($"Failed to load symbol {name}: {err}");
+            }
+            return res;
+        }
+
+        void ClearError()
+        {
+            dlerror();
+        }
+
+        string GetError()
+        {
+            var res = dlerror();
+            if (res != IntPtr.Zero)
+                return Marshal.PtrToStringAnsi(res);
+            else
+                return null;
+        }
+
+        [DllImport(NativeDll, CallingConvention = CallingConvention.Cdecl, CharSet = CharSet.Ansi)]
+        public static extern IntPtr dlopen(string fileName, int flags);
+
+        [DllImport(NativeDll, CallingConvention = CallingConvention.Cdecl, CharSet = CharSet.Ansi)]
+        private static extern IntPtr dlsym(IntPtr handle, string symbol);
+
+        [DllImport(NativeDll, CallingConvention = CallingConvention.Cdecl)]
+        private static extern int dlclose(IntPtr handle);
+
+        [DllImport(NativeDll, CallingConvention = CallingConvention.Cdecl)]
+        private static extern IntPtr dlerror();
+    }
+
+    class DarwinLoader : ILibraryLoader
+    {
+        private static int RTLD_NOW = 0x2;
+        private static int RTLD_GLOBAL = 0x8;
+        private const string NativeDll = "/usr/lib/libSystem.dylib";
+        private static IntPtr RTLD_DEFAULT = new IntPtr(-2);
+
+        public IntPtr Load(string dllToLoad)
+        {
+            var filename = $"lib{dllToLoad}.dylib";
+            ClearError();
+            var res = dlopen(filename, RTLD_NOW | RTLD_GLOBAL);
+            if (res == IntPtr.Zero)
+            {
+                var err = GetError();
+                throw new DllNotFoundException($"Could not load {filename} with flags RTLD_NOW | RTLD_GLOBAL: {err}");
+            }
+
+            return res;
+        }
+
+        public void Free(IntPtr handle)
+        {
+            dlclose(handle);
+        }
+
+        public IntPtr GetFunction(IntPtr dllHandle, string name)
+        {
+            // look in the exe if dllHandle is NULL
+            if (dllHandle == IntPtr.Zero)
+            {
+                dllHandle = RTLD_DEFAULT;
+            }
+
+            ClearError();
+            IntPtr res = dlsym(dllHandle, name);
+            if (res == IntPtr.Zero)
+            {
+                var err = GetError();
+                throw new MissingMethodException($"Failed to load symbol {name}: {err}");
+            }
+            return res;
+        }
+
+        void ClearError()
+        {
+            dlerror();
+        }
+
+        string GetError()
+        {
+            var res = dlerror();
+            if (res != IntPtr.Zero)
+                return Marshal.PtrToStringAnsi(res);
+            else
+                return null;
+        }
+
+        [DllImport(NativeDll, CallingConvention = CallingConvention.Cdecl, CharSet = CharSet.Ansi)]
+        public static extern IntPtr dlopen(String fileName, int flags);
+
+        [DllImport(NativeDll, CallingConvention = CallingConvention.Cdecl, CharSet = CharSet.Ansi)]
+        private static extern IntPtr dlsym(IntPtr handle, String symbol);
+
+        [DllImport(NativeDll, CallingConvention = CallingConvention.Cdecl)]
+        private static extern int dlclose(IntPtr handle);
+
+        [DllImport(NativeDll, CallingConvention = CallingConvention.Cdecl)]
+        private static extern IntPtr dlerror();
+    }
+
+    class WindowsLoader : ILibraryLoader
+    {
+        private const string NativeDll = "kernel32.dll";
+
+
+        public IntPtr Load(string dllToLoad)
+        {
+            var res = WindowsLoader.LoadLibrary(dllToLoad);
+            if (res == IntPtr.Zero)
+                throw new DllNotFoundException($"Could not load {dllToLoad}", new Win32Exception());
+            return res;
+        }
+
+        public IntPtr GetFunction(IntPtr hModule, string procedureName)
+        {
+            var res = WindowsLoader.GetProcAddress(hModule, procedureName);
+            if (res == IntPtr.Zero)
+                throw new MissingMethodException($"Failed to load symbol {procedureName}", new Win32Exception());
+            return res;
+        }
+
+        public void Free(IntPtr hModule) => WindowsLoader.FreeLibrary(hModule);
+
+        [DllImport(NativeDll, SetLastError = true)]
+        static extern IntPtr LoadLibrary(string dllToLoad);
+
+        [DllImport(NativeDll, SetLastError = true)]
+        static extern IntPtr GetProcAddress(IntPtr hModule, string procedureName);
+
+        [DllImport(NativeDll)]
+        static extern bool FreeLibrary(IntPtr hModule);
+    }
+}
diff --git a/src/runtime/platform/Types.cs b/src/runtime/platform/Types.cs
new file mode 100644
index 000000000..bdc51af39
--- /dev/null
+++ b/src/runtime/platform/Types.cs
@@ -0,0 +1,22 @@
+namespace Python.Runtime.Platform
+{
+    public enum MachineType
+    {
+        i386,
+        x86_64,
+        armv7l,
+        armv8,
+        Other
+    };
+
+    /// <summary>
+    /// Operating system type as reported by Python.
+    /// </summary>
+    public enum OperatingSystemType
+    {
+        Windows,
+        Darwin,
+        Linux,
+        Other
+    }
+}
diff --git a/src/runtime/runtime.cs b/src/runtime/runtime.cs
index 294ecaf48..a347651d0 100644
--- a/src/runtime/runtime.cs
+++ b/src/runtime/runtime.cs
@@ -4,99 +4,10 @@
 using System.Text;
 using System.Threading;
 using System.Collections.Generic;
+using Python.Runtime.Platform;
 
 namespace Python.Runtime
 {
-    [SuppressUnmanagedCodeSecurity]
-    internal static class NativeMethods
-    {
-#if MONO_LINUX || MONO_OSX
-#if NETSTANDARD
-        private static int RTLD_NOW = 0x2;
-#if MONO_LINUX
-        private static int RTLD_GLOBAL = 0x100;
-        private static IntPtr RTLD_DEFAULT = IntPtr.Zero;
-        private const string NativeDll = "libdl.so";
-        public static IntPtr LoadLibrary(string fileName)
-        {
-            return dlopen($"lib{fileName}.so", RTLD_NOW | RTLD_GLOBAL);
-        }
-#elif MONO_OSX
-        private static int RTLD_GLOBAL = 0x8;
-        private const string NativeDll = "/usr/lib/libSystem.dylib";
-        private static IntPtr RTLD_DEFAULT = new IntPtr(-2);
-
-        public static IntPtr LoadLibrary(string fileName)
-        {
-            return dlopen($"lib{fileName}.dylib", RTLD_NOW | RTLD_GLOBAL);
-        }
-#endif
-#else
-        private static int RTLD_NOW = 0x2;
-        private static int RTLD_SHARED = 0x20;
-#if MONO_OSX
-        private static IntPtr RTLD_DEFAULT = new IntPtr(-2);
-        private const string NativeDll = "__Internal";
-#elif MONO_LINUX
-        private static IntPtr RTLD_DEFAULT = IntPtr.Zero;
-        private const string NativeDll = "libdl.so";
-#endif
-
-        public static IntPtr LoadLibrary(string fileName)
-        {
-            return dlopen(fileName, RTLD_NOW | RTLD_SHARED);
-        }
-#endif
-
-
-        public static void FreeLibrary(IntPtr handle)
-        {
-            dlclose(handle);
-        }
-
-        public static IntPtr GetProcAddress(IntPtr dllHandle, string name)
-        {
-            // look in the exe if dllHandle is NULL
-            if (dllHandle == IntPtr.Zero)
-            {
-                dllHandle = RTLD_DEFAULT;
-            }
-
-            // clear previous errors if any
-            dlerror();
-            IntPtr res = dlsym(dllHandle, name);
-            IntPtr errPtr = dlerror();
-            if (errPtr != IntPtr.Zero)
-            {
-                throw new Exception("dlsym: " + Marshal.PtrToStringAnsi(errPtr));
-            }
-            return res;
-        }
-
-        [DllImport(NativeDll, CallingConvention = CallingConvention.Cdecl, CharSet = CharSet.Ansi)]
-        public static extern IntPtr dlopen(String fileName, int flags);
-
-        [DllImport(NativeDll, CallingConvention = CallingConvention.Cdecl, CharSet = CharSet.Ansi)]
-        private static extern IntPtr dlsym(IntPtr handle, String symbol);
-
-        [DllImport(NativeDll, CallingConvention = CallingConvention.Cdecl)]
-        private static extern int dlclose(IntPtr handle);
-
-        [DllImport(NativeDll, CallingConvention = CallingConvention.Cdecl)]
-        private static extern IntPtr dlerror();
-#else // Windows
-        private const string NativeDll = "kernel32.dll";
-
-        [DllImport(NativeDll)]
-        public static extern IntPtr LoadLibrary(string dllToLoad);
-
-        [DllImport(NativeDll)]
-        public static extern IntPtr GetProcAddress(IntPtr hModule, string procedureName);
-
-        [DllImport(NativeDll)]
-        public static extern bool FreeLibrary(IntPtr hModule);
-#endif
-    }
 
     /// <summary>
     /// Encapsulates the low-level Python C API. Note that it is
@@ -197,17 +108,6 @@ public class Runtime
         // .NET core: System.Runtime.InteropServices.RuntimeInformation.IsOSPlatform(OSPlatform.Windows)
         internal static bool IsWindows = Environment.OSVersion.Platform == PlatformID.Win32NT;
 
-        /// <summary>
-        /// Operating system type as reported by Python.
-        /// </summary>
-        public enum OperatingSystemType
-        {
-            Windows,
-            Darwin,
-            Linux,
-            Other
-        }
-
         static readonly Dictionary<string, OperatingSystemType> OperatingSystemTypeMapping = new Dictionary<string, OperatingSystemType>()
         {
             { "Windows", OperatingSystemType.Windows },
@@ -225,14 +125,6 @@ public enum OperatingSystemType
         /// </summary>
         public static string OperatingSystemName { get; private set; }
 
-        public enum MachineType
-        {
-            i386,
-            x86_64,
-            armv7l,
-            armv8,
-            Other
-        };
 
         /// <summary>
         /// Map lower-case version of the python machine name to the processor
@@ -397,24 +289,24 @@ internal static void Initialize(bool initSigs = false)
 
             Error = new IntPtr(-1);
 
+            // Initialize data about the platform we're running on. We need
+            // this for the type manager and potentially other details. Must
+            // happen after caching the python types, above.
+            InitializePlatformData();
+
             IntPtr dllLocal = IntPtr.Zero;
+            var loader = LibraryLoader.Get(OperatingSystem);
 
             if (_PythonDll != "__Internal")
             {
-                dllLocal = NativeMethods.LoadLibrary(_PythonDll);
+                dllLocal = loader.Load(_PythonDll);
             }
-            _PyObject_NextNotImplemented = NativeMethods.GetProcAddress(dllLocal, "_PyObject_NextNotImplemented");
+            _PyObject_NextNotImplemented = loader.GetFunction(dllLocal, "_PyObject_NextNotImplemented");
 
-#if !(MONO_LINUX || MONO_OSX)
             if (dllLocal != IntPtr.Zero)
             {
-                NativeMethods.FreeLibrary(dllLocal);
+                loader.Free(dllLocal);
             }
-#endif
-            // Initialize data about the platform we're running on. We need
-            // this for the type manager and potentially other details. Must
-            // happen after caching the python types, above.
-            InitializePlatformData();
 
             // Initialize modules that depend on the runtime class.
             AssemblyManager.Initialize();
diff --git a/src/runtime/typemanager.cs b/src/runtime/typemanager.cs
index a260e8dfa..127e82eaa 100644
--- a/src/runtime/typemanager.cs
+++ b/src/runtime/typemanager.cs
@@ -3,9 +3,11 @@
 using System.Collections.Generic;
 using System.Reflection;
 using System.Runtime.InteropServices;
+using Python.Runtime.Platform;
 
 namespace Python.Runtime
 {
+
     /// <summary>
     /// The TypeManager class is responsible for building binary-compatible
     /// Python type objects that are implemented in managed code.
@@ -504,15 +506,15 @@ public static NativeCode Active
             {
                 get
                 {
-                    switch(Runtime.Machine)
+                    switch (Runtime.Machine)
                     {
-                        case Runtime.MachineType.i386:
+                        case MachineType.i386:
                             return I386;
-                        case Runtime.MachineType.x86_64:
+                        case MachineType.x86_64:
                             return X86_64;
-                        case Runtime.MachineType.armv7l:
+                        case MachineType.armv7l:
                             return Armv7l;
-                        case Runtime.MachineType.armv8:
+                        case MachineType.armv8:
                             return Armv8;
                         default:
                             throw new NotImplementedException($"No support for {Runtime.MachineName}");
@@ -635,9 +637,9 @@ int MAP_ANONYMOUS
                 {
                     switch (Runtime.OperatingSystem)
                     {
-                        case Runtime.OperatingSystemType.Darwin:
+                        case OperatingSystemType.Darwin:
                             return 0x1000;
-                        case Runtime.OperatingSystemType.Linux:
+                        case OperatingSystemType.Linux:
                             return 0x20;
                         default:
                             throw new NotImplementedException($"mmap is not supported on {Runtime.OperatingSystemName}");
@@ -668,10 +670,10 @@ internal static IMemoryMapper CreateMemoryMapper()
         {
             switch (Runtime.OperatingSystem)
             {
-                case Runtime.OperatingSystemType.Darwin:
-                case Runtime.OperatingSystemType.Linux:
+                case OperatingSystemType.Darwin:
+                case OperatingSystemType.Linux:
                     return new UnixMemoryMapper();
-                case Runtime.OperatingSystemType.Windows:
+                case OperatingSystemType.Windows:
                     return new WindowsMemoryMapper();
                 default:
                     throw new NotImplementedException($"No support for {Runtime.OperatingSystemName}");