diff --git a/rc.spec b/rc.spec
index 18c8de0..463ea13 100644
--- a/rc.spec
+++ b/rc.spec
@@ -31,6 +31,7 @@ BuildRequires:  hare
 BuildRequires:  madeline
 BuildRequires:  scdoc
 BuildRequires:  zstd
+BuildRequires:  alts
 # For testing
 BuildRequires:  bc
 # End testing