diff --git a/system/devel/guile/pspec.xml b/system/devel/guile/pspec.xml
index a715fa5e..747a13a8 100644
--- a/system/devel/guile/pspec.xml
+++ b/system/devel/guile/pspec.xml
@@ -19,6 +19,7 @@
             <Dependency>gc-devel</Dependency>
             <Dependency>gettext-devel</Dependency>
             <Dependency>gmp-devel</Dependency>
+            <Dependency>libunistring-devel</Dependency>
         </BuildDependencies>
         <Patches>
         </Patches>