diff --git a/lib/CMakeLists.txt b/lib/CMakeLists.txt
index 07664727..34dfb94b 100644
--- a/lib/CMakeLists.txt
+++ b/lib/CMakeLists.txt
@@ -30,7 +30,7 @@ if(TREE_SITTER_FEATURE_WASM)
     message(CHECK_START "Looking for wasmtime headers")
     find_path(WASMTIME_INCLUDE_DIR wasmtime.h
               PATHS ENV DEP_WASMTIME_C_API_INCLUDE)
-    if(NOT ${WASMTIME_INCLUDE_DIR})
+    if(NOT WASMTIME_INCLUDE_DIR)
       unset(WASMTIME_INCLUDE_DIR CACHE)
       message(FATAL_ERROR "Could not find wasmtime headers.\nDid you forget to set CMAKE_INCLUDE_PATH?")
     endif()
@@ -46,7 +46,7 @@ if(TREE_SITTER_FEATURE_WASM)
     else()
       find_library(WASMTIME_LIBRARY libwasmtime.a)
     endif()
-    if(NOT ${WASMTIME_LIBRARY})
+    if(NOT WASMTIME_LIBRARY)
       unset(WASMTIME_LIBRARY CACHE)
       message(FATAL_ERROR "Could not find wasmtime library.\nDid you forget to set CMAKE_LIBRARY_PATH?")
     endif()