diff --git a/zig/src/native/cuda.zig b/zig/src/native/cuda.zig
index 84f106a0ff..96f005bdb7 100644
--- a/zig/src/native/cuda.zig
+++ b/zig/src/native/cuda.zig
@@ -176,7 +176,7 @@ pub const Host = struct {
     /// The family's backend, each call made with the context current on the calling thread.
     fn backend(h: *Host) lanes.backend.Backend {
         h.vtable = lane_backend.vtable(Host, h.inner.vtable.*);
-        return .{ .ptr = h, .vtable = &h.vtable };
+        return .{ .ptr = h, .vtable = &h.vtable, .first_before_draft = h.inner.first_before_draft };
     }
 };
 
@@ -487,12 +487,15 @@ test {
     _ = windows;
 }
 
-test "the lane core sees a family's prefill_step through the lane backend, so a served prompt can step" {
+test "CUDA host preserves prefill_step and first-before-draft capability" {
     var target: lanes.fake.Fake = .{ .gpa = std.testing.allocator, .prefill_chunks = 3 };
     defer target.deinit();
     var h: Host = undefined;
     h.inner = target.stepped();
     try std.testing.expect(h.backend().vtable.prefill_step != null);
+    try std.testing.expect(!h.backend().first_before_draft);
+    h.inner.first_before_draft = true;
+    try std.testing.expect(h.backend().first_before_draft);
 }
 
 test "every registered family and d1's decision engine are listed for capabilities" {