diff --git a/src/Umbraco.Core/Cache/CacheKeys.cs b/src/Umbraco.Abstractions/Cache/CacheKeys.cs
similarity index 100%
rename from src/Umbraco.Core/Cache/CacheKeys.cs
rename to src/Umbraco.Abstractions/Cache/CacheKeys.cs
diff --git a/src/Umbraco.Core/Cache/IAppCache.cs b/src/Umbraco.Abstractions/Cache/IAppCache.cs
similarity index 100%
rename from src/Umbraco.Core/Cache/IAppCache.cs
rename to src/Umbraco.Abstractions/Cache/IAppCache.cs
diff --git a/src/Umbraco.Core/Cache/ICacheRefresher.cs b/src/Umbraco.Abstractions/Cache/ICacheRefresher.cs
similarity index 94%
rename from src/Umbraco.Core/Cache/ICacheRefresher.cs
rename to src/Umbraco.Abstractions/Cache/ICacheRefresher.cs
index a9ac76af6e..257d1da05a 100644
--- a/src/Umbraco.Core/Cache/ICacheRefresher.cs
+++ b/src/Umbraco.Abstractions/Cache/ICacheRefresher.cs
@@ -25,7 +25,7 @@ namespace Umbraco.Core.Cache
     /// This is much better for performance when we're not running in a load balanced environment so we can refresh the cache
     /// against a already resolved object instead of looking the object back up by id.
     /// </remarks>
-    interface ICacheRefresher<T> : ICacheRefresher
+    public interface ICacheRefresher<T> : ICacheRefresher
     {
         void Refresh(T instance);
         void Remove(T instance);
diff --git a/src/Umbraco.Core/Cache/IJsonCacheRefresher.cs b/src/Umbraco.Abstractions/Cache/IJsonCacheRefresher.cs
similarity index 87%
rename from src/Umbraco.Core/Cache/IJsonCacheRefresher.cs
rename to src/Umbraco.Abstractions/Cache/IJsonCacheRefresher.cs
index 29f1422a8f..005d3c5101 100644
--- a/src/Umbraco.Core/Cache/IJsonCacheRefresher.cs
+++ b/src/Umbraco.Abstractions/Cache/IJsonCacheRefresher.cs
@@ -3,7 +3,7 @@
     /// <summary>
     /// A cache refresher that supports refreshing or removing cache based on a custom Json payload
     /// </summary>
-    interface IJsonCacheRefresher : ICacheRefresher
+    public interface IJsonCacheRefresher : ICacheRefresher
     {
         /// <summary>
         /// Refreshes, clears, etc... any cache based on the information provided in the json
diff --git a/src/Umbraco.Core/Cache/IPayloadCacheRefresher.cs b/src/Umbraco.Abstractions/Cache/IPayloadCacheRefresher.cs
similarity index 83%
rename from src/Umbraco.Core/Cache/IPayloadCacheRefresher.cs
rename to src/Umbraco.Abstractions/Cache/IPayloadCacheRefresher.cs
index 322e65654c..a30245a239 100644
--- a/src/Umbraco.Core/Cache/IPayloadCacheRefresher.cs
+++ b/src/Umbraco.Abstractions/Cache/IPayloadCacheRefresher.cs
@@ -3,7 +3,7 @@
     /// <summary>
     /// A cache refresher that supports refreshing cache based on a custom payload
     /// </summary>
-    interface IPayloadCacheRefresher<TPayload> : IJsonCacheRefresher
+    public interface IPayloadCacheRefresher<TPayload> : IJsonCacheRefresher
     {
         /// <summary>
         /// Refreshes, clears, etc... any cache based on the information provided in the payload
diff --git a/src/Umbraco.Core/Umbraco.Core.csproj b/src/Umbraco.Core/Umbraco.Core.csproj
index 51b87621f4..842fa1ede2 100755
--- a/src/Umbraco.Core/Umbraco.Core.csproj
+++ b/src/Umbraco.Core/Umbraco.Core.csproj
@@ -118,7 +118,6 @@
     <Compile Include="Cache\AppPolicedCacheDictionary.cs" />
     <Compile Include="Compose\AuditEventsComponent.cs" />
     <Compile Include="Cache\AppCaches.cs" />
-    <Compile Include="Cache\CacheKeys.cs" />
     <Compile Include="Cache\AppCacheExtensions.cs" />
     <Compile Include="Cache\CacheRefresherBase.cs" />
     <Compile Include="Cache\CacheRefresherCollection.cs" />
@@ -131,10 +130,6 @@
     <Compile Include="Cache\FullDataSetRepositoryCachePolicy.cs" />
     <Compile Include="Cache\HttpRequestAppCache.cs" />
     <Compile Include="Cache\WebCachingAppCache.cs" />
-    <Compile Include="Cache\IAppCache.cs" />
-    <Compile Include="Cache\ICacheRefresher.cs" />
-    <Compile Include="Cache\IJsonCacheRefresher.cs" />
-    <Compile Include="Cache\IPayloadCacheRefresher.cs" />
     <Compile Include="Cache\IRepositoryCachePolicy.cs" />
     <Compile Include="Cache\IAppPolicyCache.cs" />
     <Compile Include="Cache\IsolatedCaches.cs" />
@@ -1445,10 +1440,6 @@
   <ItemGroup>
     <EmbeddedResource Include="FileResources\Files.resx" />
   </ItemGroup>
-  <ItemGroup>
-    <Folder Include="Auditing\" />
-    <Folder Include="Exceptions\" />
-  </ItemGroup>
   <ItemGroup>
     <ProjectReference Include="..\Umbraco.Abstractions\Umbraco.Abstractions.csproj">
       <Project>{29aa69d9-b597-4395-8d42-43b1263c240a}</Project>
diff --git a/src/Umbraco.Web.UI/Umbraco.Web.UI.csproj b/src/Umbraco.Web.UI/Umbraco.Web.UI.csproj
index 7ae996a6c5..993b835252 100644
--- a/src/Umbraco.Web.UI/Umbraco.Web.UI.csproj
+++ b/src/Umbraco.Web.UI/Umbraco.Web.UI.csproj
@@ -109,6 +109,10 @@
     <PackageReference Include="Umbraco.SqlServerCE" Version="4.0.0.1" />
   </ItemGroup>
   <ItemGroup>
+    <ProjectReference Include="..\Umbraco.Abstractions\Umbraco.Abstractions.csproj">
+      <Project>{29aa69d9-b597-4395-8d42-43b1263c240a}</Project>
+      <Name>Umbraco.Abstractions</Name>
+    </ProjectReference>
     <ProjectReference Include="..\Umbraco.Core\Umbraco.Core.csproj">
       <Project>{31785bc3-256c-4613-b2f5-a1b0bdded8c1}</Project>
       <Name>Umbraco.Core</Name>