-# how to specify? - rpm.org adds arch provides on packages (__isa), uncomment once we switch
-#BuildRequires: curl-devel(x86-64)
-#BuildRequires: libgit2-devel(x86-64)
-#BuildRequires: llvm-devel(x86-64)>= 7.0
-#BuildRequires: openssl-devel(x86-64)
-#BuildRequires: zlib-devel(x86-64)
+%{?with_system_llvm:BuildRequires: llvm-devel(x86-64) >= 9.0}
+BuildRequires: openssl-devel(x86-64)
+BuildRequires: zlib-devel(x86-64)