diff --git a/circle.yml b/circle.yml
index 6851c07..ef4475f 100644
--- a/circle.yml
+++ b/circle.yml
@@ -9,6 +9,7 @@ jobs:
     - run:
         name: "Check code format"
         command: |
+          clang-format --version
           find examples include lib test -name '*.hpp' -o -name '*.cpp' -o -name '*.h' -o -name '*.c' | xargs clang-format -i
           git diff --color --exit-code
     - run:
diff --git a/test/vmtester/tests.cpp b/test/vmtester/tests.cpp
index 0c9384e..8796b19 100644
--- a/test/vmtester/tests.cpp
+++ b/test/vmtester/tests.cpp
@@ -111,9 +111,9 @@ TEST_F(evmc_vm_test, version)
 
 TEST_F(evmc_vm_test, set_tracer)
 {
-    static const auto tracer_callback = [](evmc_tracer_context*, size_t, evmc_status_code, int64_t,
-                                           size_t, const evmc_uint256be*, size_t, size_t, size_t,
-                                           const uint8_t*) noexcept {};
+    static const auto tracer_callback =
+        [](evmc_tracer_context*, size_t, evmc_status_code, int64_t, size_t, const evmc_uint256be*,
+           size_t, size_t, size_t, const uint8_t*) noexcept {};
     if (vm->set_tracer)
         vm->set_tracer(vm, tracer_callback, nullptr);
 }