diff --git a/webgl/transcoder/CMakeLists.txt b/webgl/transcoder/CMakeLists.txt
index 5e338c6..945be6f 100644
--- a/webgl/transcoder/CMakeLists.txt
+++ b/webgl/transcoder/CMakeLists.txt
@@ -10,10 +10,12 @@ if (EMSCRIPTEN)
     basis_wrappers.cpp
   )
 
+  target_compile_definitions(basis_transcoder.js PRIVATE NDEBUG BASISD_SUPPORT_BC7=0)
+  target_compile_options(basis_transcoder.js PRIVATE -O3)
   target_include_directories(basis_transcoder.js PRIVATE ../../transcoder)
 
   set_target_properties(basis_transcoder.js PROPERTIES
       OUTPUT_NAME "basis_transcoder"
       SUFFIX ".js"
-      LINK_FLAGS "--bind -s ALLOW_MEMORY_GROWTH=1 -O3 -s ASSERTIONS=0 -s MALLOC=emmalloc -DNDEBUG -DBASISD_SUPPORT_BC7=0")
+      LINK_FLAGS "--bind -s ALLOW_MEMORY_GROWTH=1 -O3 -s ASSERTIONS=0 -s MALLOC=emmalloc")
 endif()