diff --git a/BUILD.bazel b/BUILD.bazel
index 319421f..152657e 100644
--- a/BUILD.bazel
+++ b/BUILD.bazel
@@ -21,7 +21,7 @@ licenses(["notice"])
 exports_files(["LICENSE"])
 
 cc_library(
-    name = "transformer_ops",
+    name = "ops",
     hdrs = [
         "ops.h",
     ],
@@ -38,6 +38,21 @@ cc_library(
     ],
 )
 
+cc_test(
+    name = "ops_test",
+    size = "small",
+    srcs = ["ops_test.cc"],
+    local_defines = ["HWY_IS_TEST"],
+    # for test_suite.
+    tags = ["hwy_ops_test"],
+    deps = [
+        ":ops",
+        "@googletest//:gtest_main",
+        "@hwy//:hwy",
+        "@hwy//:hwy_test_util",
+    ],
+)
+
 cc_library(
     name = "args",
     hdrs = [
@@ -59,7 +74,7 @@ cc_library(
     ],
     deps = [
         ":args",
-        ":transformer_ops",
+        ":ops",
         # "//base",
         "//compression:compress",
         "@hwy//:hwy",
diff --git a/ops_test.cc b/ops_test.cc
index e19106b..f908c39 100644
--- a/ops_test.cc
+++ b/ops_test.cc
@@ -17,6 +17,9 @@
 #define HWY_DISABLED_TARGETS HWY_SCALAR
 #endif
 
+#include <array>
+#include <random>
+
 #include "hwy/aligned_allocator.h"
 #include "hwy/base.h"
 
@@ -25,9 +28,10 @@
 #define HWY_TARGET_INCLUDE "ops_test.cc"  //NOLINT
 // clang-format on
 #include "hwy/foreach_target.h"  // IWYU pragma: keep
-// copybara:import_next_line:gemma_cpp
 #include "hwy/highway.h"
 #include "hwy/tests/test_util-inl.h"
+// After highway.h
+// copybara:import_next_line:gemma_cpp
 #include "ops.h"
 
 HWY_BEFORE_NAMESPACE();
@@ -282,6 +286,7 @@ struct TestSoftmax {
   template <class D>
   void operator()(D d, size_t count, size_t misalign_a, size_t misalign_b,
                   hwy::RandomState& rng) {
+    if (count == 0) return;  // *Softmax would assert
     using T = hn::TFromD<D>;
 
     hwy::AlignedFreeUniquePtr<T[]> px =