diff --git a/install-cmake.sh b/install-cmake.sh
index e63560c1..cb384a94 100755
--- a/install-cmake.sh
+++ b/install-cmake.sh
@@ -832,13 +832,22 @@ build_from_tarball_boost()
     initialize_boost_configuration
     initialize_boost_icu_configuration
 
+    guessed_toolset=`./tools/build/src/engine/build.sh --guess-toolset`
+    CXXFLAGS="-w" ./tools/build/src/engine/build.sh ${guessed_toolset} --cxxflags="-w"
+    cp tools/build/src/engine/b2 .
+    if [[ (x"$BOOST_CXXFLAGS" == "x") ]]; then
+        BOOST_CXXFLAGS="cxxflags=${BOOST_FLAGS[@]}"
+    else
+        BOOST_CXXFLAGS="$BOOST_CXXFLAGS ${BOOST_FLAGS[@]}"
+    fi
+
     display_message "Libbitcoin boost configuration."
     display_message "--------------------------------------------------------------------"
     display_message "variant               : release"
     display_message "threading             : multi"
     display_message "toolset               : $CC"
-    display_message "cxxflags              : $STDLIB_FLAG"
-    display_message "linkflags             : $STDLIB_FLAG"
+    display_message "boost cxxflags        : $BOOST_CXXFLAGS"
+    display_message "boost linkflags       : $BOOST_LINKFLAGS"
     display_message "link                  : $BOOST_LINK"
     display_message "boost.locale.iconv    : $BOOST_ICU_ICONV"
     display_message "boost.locale.posix    : $BOOST_ICU_POSIX"
@@ -852,12 +861,9 @@ build_from_tarball_boost()
     display_message "--reconfigure         : [ignore cached configuration]"
     display_message "--prefix              : $PREFIX"
     display_message "BOOST_OPTIONS         : $*"
+    display_message "cxxflags (ignored)    : $CXXFLAGS"
     display_message "--------------------------------------------------------------------"
 
-    guessed_toolset=`./tools/build/src/engine/build.sh --guess-toolset`
-    CXXFLAGS="-w" ./tools/build/src/engine/build.sh ${guessed_toolset} --cxxflags="-w"
-    cp tools/build/src/engine/b2 .
-
     ./bootstrap.sh \
         "--with-bjam=./b2" \
         "--prefix=$PREFIX" \
@@ -961,6 +967,11 @@ remove_install_options
 ICU_FLAGS=(
 "-w")
 
+# Define boost flags.
+#------------------------------------------------------------------------------
+BOOST_FLAGS=(
+"-Wno-enum-constexpr-conversion")
+
 # Define secp256k1 flags.
 #------------------------------------------------------------------------------
 SECP256K1_FLAGS=(
diff --git a/install-cmakepresets.sh b/install-cmakepresets.sh
index 916cc3e0..3d649ebf 100755
--- a/install-cmakepresets.sh
+++ b/install-cmakepresets.sh
@@ -881,13 +881,22 @@ build_from_tarball_boost()
     initialize_boost_configuration
     initialize_boost_icu_configuration
 
+    guessed_toolset=`./tools/build/src/engine/build.sh --guess-toolset`
+    CXXFLAGS="-w" ./tools/build/src/engine/build.sh ${guessed_toolset} --cxxflags="-w"
+    cp tools/build/src/engine/b2 .
+    if [[ (x"$BOOST_CXXFLAGS" == "x") ]]; then
+        BOOST_CXXFLAGS="cxxflags=${BOOST_FLAGS[@]}"
+    else
+        BOOST_CXXFLAGS="$BOOST_CXXFLAGS ${BOOST_FLAGS[@]}"
+    fi
+
     display_message "Libbitcoin boost configuration."
     display_message "--------------------------------------------------------------------"
     display_message "variant               : release"
     display_message "threading             : multi"
     display_message "toolset               : $CC"
-    display_message "cxxflags              : $STDLIB_FLAG"
-    display_message "linkflags             : $STDLIB_FLAG"
+    display_message "boost cxxflags        : $BOOST_CXXFLAGS"
+    display_message "boost linkflags       : $BOOST_LINKFLAGS"
     display_message "link                  : $BOOST_LINK"
     display_message "boost.locale.iconv    : $BOOST_ICU_ICONV"
     display_message "boost.locale.posix    : $BOOST_ICU_POSIX"
@@ -901,12 +910,9 @@ build_from_tarball_boost()
     display_message "--reconfigure         : [ignore cached configuration]"
     display_message "--prefix              : $PREFIX"
     display_message "BOOST_OPTIONS         : $*"
+    display_message "cxxflags (ignored)    : $CXXFLAGS"
     display_message "--------------------------------------------------------------------"
 
-    guessed_toolset=`./tools/build/src/engine/build.sh --guess-toolset`
-    CXXFLAGS="-w" ./tools/build/src/engine/build.sh ${guessed_toolset} --cxxflags="-w"
-    cp tools/build/src/engine/b2 .
-
     ./bootstrap.sh \
         "--with-bjam=./b2" \
         "--prefix=$PREFIX" \
@@ -1013,6 +1019,11 @@ remove_install_options
 ICU_FLAGS=(
 "-w")
 
+# Define boost flags.
+#------------------------------------------------------------------------------
+BOOST_FLAGS=(
+"-Wno-enum-constexpr-conversion")
+
 # Define secp256k1 flags.
 #------------------------------------------------------------------------------
 SECP256K1_FLAGS=(
diff --git a/install.sh b/install.sh
index 44f1fff8..00d93c46 100755
--- a/install.sh
+++ b/install.sh
@@ -707,13 +707,22 @@ build_from_tarball_boost()
     initialize_boost_configuration
     initialize_boost_icu_configuration
 
+    guessed_toolset=`./tools/build/src/engine/build.sh --guess-toolset`
+    CXXFLAGS="-w" ./tools/build/src/engine/build.sh ${guessed_toolset} --cxxflags="-w"
+    cp tools/build/src/engine/b2 .
+    if [[ (x"$BOOST_CXXFLAGS" == "x") ]]; then
+        BOOST_CXXFLAGS="cxxflags=${BOOST_FLAGS[@]}"
+    else
+        BOOST_CXXFLAGS="$BOOST_CXXFLAGS ${BOOST_FLAGS[@]}"
+    fi
+
     display_message "Libbitcoin boost configuration."
     display_message "--------------------------------------------------------------------"
     display_message "variant               : release"
     display_message "threading             : multi"
     display_message "toolset               : $CC"
-    display_message "cxxflags              : $STDLIB_FLAG"
-    display_message "linkflags             : $STDLIB_FLAG"
+    display_message "boost cxxflags        : $BOOST_CXXFLAGS"
+    display_message "boost linkflags       : $BOOST_LINKFLAGS"
     display_message "link                  : $BOOST_LINK"
     display_message "boost.locale.iconv    : $BOOST_ICU_ICONV"
     display_message "boost.locale.posix    : $BOOST_ICU_POSIX"
@@ -727,12 +736,9 @@ build_from_tarball_boost()
     display_message "--reconfigure         : [ignore cached configuration]"
     display_message "--prefix              : $PREFIX"
     display_message "BOOST_OPTIONS         : $*"
+    display_message "cxxflags (ignored)    : $CXXFLAGS"
     display_message "--------------------------------------------------------------------"
 
-    guessed_toolset=`./tools/build/src/engine/build.sh --guess-toolset`
-    CXXFLAGS="-w" ./tools/build/src/engine/build.sh ${guessed_toolset} --cxxflags="-w"
-    cp tools/build/src/engine/b2 .
-
     ./bootstrap.sh \
         "--with-bjam=./b2" \
         "--prefix=$PREFIX" \
@@ -835,6 +841,11 @@ set_with_boost_prefix
 ICU_FLAGS=(
 "-w")
 
+# Define boost flags.
+#------------------------------------------------------------------------------
+BOOST_FLAGS=(
+"-Wno-enum-constexpr-conversion")
+
 # Define secp256k1 flags.
 #------------------------------------------------------------------------------
 SECP256K1_FLAGS=(