diff --git a/CLAUDE.md b/CLAUDE.md
index 2e14c3f..85db8b1 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -71,10 +71,8 @@ cp FSharp.Core.4.4.3.0/FSharp.Core.dll Debug/
 cd Debug && mono /path/to/nunit3-console.exe Test.MMManaged.dll
 ```
 
-Known: 6 tests fail on linux regardless of the change under test (TestMesh, TestMeshTransform
-x2, TestModDB, TestModDBInterop, TestYaml).  They all die in `Util.TestDataDir`'s static
-constructor, which searches windows-style relative paths for TestData.  Compare against a
-master build before assuming a failure is yours.
+All tests pass on linux.  `State.reloadSnapshotProfiles` logs an error about a missing
+`TestData/SnapshotProfiles` dir during the interop test; that is expected and not a failure.
 
 ## Interop notes
 
diff --git a/Test.MMManaged/TestMesh.fs b/Test.MMManaged/TestMesh.fs
index 23be289..339c597 100644
--- a/Test.MMManaged/TestMesh.fs
+++ b/Test.MMManaged/TestMesh.fs
@@ -7,7 +7,7 @@ open ModelMod
 open ModelMod.CoreTypes
 
 let monolith =
-    let mpath = Path.Combine(Util.TestDataDir,"monolithref.mmobj")
+    let mpath = Path.Combine(Util.TestDataDir,"MonolithRef.mmobj")
     MeshUtil.readFrom(mpath,CoreTypes.GPUReplacement,CoreTypes.DefaultReadFlags)
 
 open MonoGameHelpers
diff --git a/Test.MMManaged/TestMeshTransform.fs b/Test.MMManaged/TestMeshTransform.fs
index 6b795f8..ffcbcba 100644
--- a/Test.MMManaged/TestMeshTransform.fs
+++ b/Test.MMManaged/TestMeshTransform.fs
@@ -10,7 +10,7 @@ open ModelMod.CoreTypes
 let vecEq = Util.veqEqEpsilon 0.000001f
 
 let monolith =
-    let mpath = Path.Combine(Util.TestDataDir,"monolithref.mmobj")
+    let mpath = Path.Combine(Util.TestDataDir,"MonolithRef.mmobj")
     MeshUtil.readFrom(mpath,CoreTypes.GPUReplacement,CoreTypes.DefaultReadFlags)
 
 [<Test>]
diff --git a/Test.MMManaged/Util.fs b/Test.MMManaged/Util.fs
index 99c4043..2758e3e 100644
--- a/Test.MMManaged/Util.fs
+++ b/Test.MMManaged/Util.fs
@@ -12,22 +12,18 @@ let veqEqEpsilon (ep:float32) (v1:Vec3F) (v2:Vec3F) =
     let dz = Math.Abs(v1.Z - v2.Z)
     dx < ep && dy < ep && dz < ep
 
-let TestDataDir = 
-    let asmPath = Assembly.GetExecutingAssembly().CodeBase.Replace("file:///","")
-
-    let paths = [ @"..\..\TestData"; @"..\TestData"; "@\..\..\..\..\..\TestData" ]
-
-    let paths = paths |> List.map (fun p -> Path.GetFullPath(Path.Combine(asmPath,p)))
-
-    let found =     
-        paths |> List.tryPick (fun p -> 
-            if Directory.Exists p then
-                Some(p)
-            else
-                None
-    )
-
-    match found with 
-    | None -> failwithf "Failed to locate test data directory, searched: %A" paths
+let TestDataDir =
+    // walk up from the assembly dir looking for TestData; the output layout differs between the
+    // VS and dotnet builds.  avoid literal path separators, they aren't portable.
+    let asmDir = Path.GetDirectoryName(Uri(Assembly.GetExecutingAssembly().CodeBase).LocalPath)
+
+    let rec search (dir:DirectoryInfo) levels =
+        if isNull (box dir) || levels = 0 then
+            None
+        else
+            let cand = Path.Combine(dir.FullName, "TestData")
+            if Directory.Exists cand then Some(cand) else search dir.Parent (levels-1)
+
+    match search (DirectoryInfo(asmDir)) 6 with
+    | None -> failwithf "Failed to locate test data directory at or above: %s" asmDir
     | Some path -> path
-    
\ No newline at end of file