diff --git a/lib/mammoth/CMakeLists.txt b/lib/mammoth/CMakeLists.txt
index fa2bf6b..5ceed59 100644
--- a/lib/mammoth/CMakeLists.txt
+++ b/lib/mammoth/CMakeLists.txt
@@ -17,7 +17,6 @@ target_include_directories(mammoth
 
 target_link_libraries(mammoth
   glacier
-  victoriafalls_yunq
   yellowstone_yunq
   voyageurs_yunq
   zion_stub
diff --git a/rust/lib/client/denali_client/build.rs b/rust/lib/client/denali_client/build.rs
index 67e593c..f5228b3 100644
--- a/rust/lib/client/denali_client/build.rs
+++ b/rust/lib/client/denali_client/build.rs
@@ -1,7 +1,7 @@
 use std::fs;
 
 fn main() {
-    let input_file = "../../../../sys/denali/lib/denali/denali.yunq";
+    let input_file = "../../../sys/denali/denali.yunq";
 
     println!("cargo::rerun-if-changed={input_file}");
 
diff --git a/rust/sys/denali/build.rs b/rust/sys/denali/build.rs
index d5ac830..a57b29c 100644
--- a/rust/sys/denali/build.rs
+++ b/rust/sys/denali/build.rs
@@ -1,7 +1,7 @@
 use std::fs;
 
 fn main() {
-    let input_file = "../../../sys/denali/lib/denali/denali.yunq";
+    let input_file = "denali.yunq";
 
     println!("cargo::rerun-if-changed={input_file}");
 
diff --git a/rust/sys/denali/denali.yunq b/rust/sys/denali/denali.yunq
new file mode 100644
index 0000000..8348968
--- /dev/null
+++ b/rust/sys/denali/denali.yunq
@@ -0,0 +1,28 @@
+interface Denali {
+  method Read(ReadRequest) -> (ReadResponse); 
+  method ReadMany(ReadManyRequest) -> (ReadResponse);
+}
+
+message DiskBlock {
+  u64 lba;
+  u64 size;
+}
+
+message ReadRequest {
+  u64 device_id;
+  DiskBlock block;
+}
+
+
+message ReadManyRequest {
+  u64 device_id;
+  repeated DiskBlock blocks;
+}
+
+message ReadResponse {
+  u64 device_id;
+  u64 size;
+  capability memory;
+}
+
+
diff --git a/rust/sys/victoriafalls/build.rs b/rust/sys/victoriafalls/build.rs
index 7e2d7d5..ad812f3 100644
--- a/rust/sys/victoriafalls/build.rs
+++ b/rust/sys/victoriafalls/build.rs
@@ -1,7 +1,7 @@
 use std::fs;
 
 fn main() {
-    let input_file = "../../../sys/victoriafalls/lib/victoriafalls/victoriafalls.yunq";
+    let input_file = "victoriafalls.yunq";
 
     println!("cargo::rerun-if-changed={input_file}");
 
diff --git a/rust/sys/victoriafalls/victoriafalls.yunq b/rust/sys/victoriafalls/victoriafalls.yunq
new file mode 100644
index 0000000..1cc0d45
--- /dev/null
+++ b/rust/sys/victoriafalls/victoriafalls.yunq
@@ -0,0 +1,24 @@
+interface VFS {
+  method OpenFile(OpenFileRequest) -> (OpenFileResponse);
+  method GetDirectory(GetDirectoryRequest) -> (Directory);
+}
+
+message OpenFileRequest {
+  string path;
+}
+
+message OpenFileResponse {
+  string path;
+  u64 size;
+  capability memory;
+}
+
+message GetDirectoryRequest {
+  string path;
+}
+
+message Directory {
+  // , separated list of filenames until we have repeated strings.
+  string filenames;
+}
+
diff --git a/sys/CMakeLists.txt b/sys/CMakeLists.txt
index 3f4f9ca..b6fe722 100644
--- a/sys/CMakeLists.txt
+++ b/sys/CMakeLists.txt
@@ -1,7 +1,5 @@
 set(CMAKE_SHARED_LIBRARY_LINK_CXX_FLAGS "")
 
-add_subdirectory(denali)
-add_subdirectory(victoriafalls)
 add_subdirectory(voyageurs)
 add_subdirectory(yellowstone)