diff --git a/recipe/build.sh b/recipe/build.sh
index 5abe54e..8479d9d 100644
--- a/recipe/build.sh
+++ b/recipe/build.sh
@@ -3,7 +3,7 @@ set -ex
 
 export DISABLE_AUTOBREW=1
 
-# set C++17 due to abseil
+# arrow uses C++17
 export ARROW_R_CXXFLAGS="${ARROW_R_CXXFLAGS} -std=c++17"
 
 if [[ "${target_platform}" == osx-* ]]; then
@@ -11,4 +11,5 @@ if [[ "${target_platform}" == osx-* ]]; then
     export ARROW_R_CXXFLAGS="${ARROW_R_CXXFLAGS} -D_LIBCPP_DISABLE_AVAILABILITY"
 fi
 
+# ${R_ARGS} necessary to support cross-compilation
 ${R} CMD INSTALL --build r/. ${R_ARGS}