diff --git a/linux/Makefile b/linux/Makefile
index fd34255f..a13ed1a6 100644
--- a/linux/Makefile
+++ b/linux/Makefile
@@ -333,7 +333,10 @@ $(BUILD_PREFIX)/libruby.so.3.1: $(DOWNLOADS)/ruby/Makefile
 
 $(DOWNLOADS)/ruby/Makefile: $(DOWNLOADS)/ruby/configure
 	cd $(DOWNLOADS)/ruby; \
-	$(CONFIGURE) $(RUBY_CONFIGURE_ARGS) $(RUBY_FLAGS)
+	export $(CONFIGURE_ENV); \
+	export CFLAGS="-flto=full $$CFLAGS"; \
+	export LDFLAGS="-flto=full $$LDFLAGS"; \
+	./configure $(CONFIGURE_ARGS) $(RUBY_CONFIGURE_ARGS) $(RUBY_FLAGS)
 
 $(DOWNLOADS)/ruby/configure: $(DOWNLOADS)/ruby/*.c
 	cd $(DOWNLOADS)/ruby; autoreconf -i
diff --git a/macos/Dependencies/common.make b/macos/Dependencies/common.make
index f4919ca1..f9a07193 100644
--- a/macos/Dependencies/common.make
+++ b/macos/Dependencies/common.make
@@ -311,7 +311,10 @@ $(LIBDIR)/libruby.3.1.dylib: $(DOWNLOADS)/ruby/Makefile
 
 $(DOWNLOADS)/ruby/Makefile: $(DOWNLOADS)/ruby/configure
 	cd $(DOWNLOADS)/ruby; \
-	$(CONFIGURE) $(RUBY_CONFIGURE_ARGS) $(RUBY_FLAGS)
+	export $(CONFIGURE_ENV); \
+	export CFLAGS="-flto=full $$CFLAGS"; \
+	export LDFLAGS="-flto=full $$LDFLAGS"; \
+	./configure $(CONFIGURE_ARGS) $(RUBY_CONFIGURE_ARGS) $(RUBY_FLAGS)
 
 $(DOWNLOADS)/ruby/configure: $(DOWNLOADS)/ruby/*.c
 	cd $(DOWNLOADS)/ruby; autoreconf -i
diff --git a/windows/Makefile b/windows/Makefile
index a201c116..301b082c 100755
--- a/windows/Makefile
+++ b/windows/Makefile
@@ -320,7 +320,10 @@ $(BUILD_PREFIX)/$(RB_PREFIX)-ruby310.dll: $(DOWNLOADS)/ruby/Makefile
 
 $(DOWNLOADS)/ruby/Makefile: $(DOWNLOADS)/ruby/configure
 	cd $(DOWNLOADS)/ruby; \
-	$(CONFIGURE) $(RUBY_CONFIGURE_ARGS) $(RUBY_FLAGS)
+	export $(CONFIGURE_ENV); \
+	export CFLAGS="-flto $$CFLAGS"; \
+	export LDFLAGS="-flto $$LDFLAGS"; \
+	./configure $(CONFIGURE_ARGS) $(RUBY_CONFIGURE_ARGS) $(RUBY_FLAGS)
 
 $(DOWNLOADS)/ruby/configure: $(DOWNLOADS)/ruby/*.c
 	cd $(DOWNLOADS)/ruby; autoreconf -i