diff --git a/Makefile b/Makefile
index 7a7add57..220880b4 100644
--- a/Makefile
+++ b/Makefile
@@ -34,7 +34,8 @@ CXX_FLAGS ?= -g
 SANITIZER ?= default
 SOURCEDIR = $(CURDIR)
 BUILDROOT = build
-BUILD     = $(BUILDROOT)/$(SANITIZER)
+SYSTEM    = $(shell uname -s)
+BUILD     = $(BUILDROOT)/$(SYSTEM)/$(SANITIZER)
 EXAMPLE   = beman.execution.examples.stop_token
 CMAKE_CXX_COMPILER=$(COMPILER)
 
@@ -113,6 +114,7 @@ check:
 	done | tsort > /dev/null
 
 build/$(SANITIZER)/compile_commands.json: $(SANITIZER)
+
 clang-tidy: $(BUILD)/compile_commands.json
 	run-clang-tidy -p $(BUILD) tests examples
 
@@ -138,7 +140,7 @@ clean-doc:
 	$(RM) -r docs/html docs/latex
 
 clean: clean-doc
-	$(RM) -r $(BUILD)
+	cmake --build $(BUILD) --target clean
 	$(RM) mkerr olderr *~
 
 distclean: clean
diff --git a/include/beman/execution/detail/sched_attrs.hpp b/include/beman/execution/detail/sched_attrs.hpp
index 67eb6501..5d8e8372 100644
--- a/include/beman/execution/detail/sched_attrs.hpp
+++ b/include/beman/execution/detail/sched_attrs.hpp
@@ -24,7 +24,8 @@ class sched_attrs {
 
   public:
     template <typename S>
-    explicit sched_attrs(S s) : sched(::std::move(s)) {}
+        requires(!::std::same_as<sched_attrs, ::std::remove_cvref_t<S>>)
+    explicit sched_attrs(S&& s) : sched(::std::forward<S>(s)) {}
 
     template <typename Tag>
     auto query(const ::beman::execution::get_completion_scheduler_t<Tag>&) const noexcept {