diff --git a/spack.yaml b/spack.yaml
index 31386d2..6e100e5 100644
--- a/spack.yaml
+++ b/spack.yaml
@@ -38,7 +38,7 @@ spack:
     all:
       require:
         - '%intel@2021.10.0'
-        - target=x86_64
+        - 'target=x86_64'
   view: true
   concretizer:
     unify: true