diff --git a/crates/blockchain/src/lib.rs b/crates/blockchain/src/lib.rs
index 98961c91..2c8cd212 100644
--- a/crates/blockchain/src/lib.rs
+++ b/crates/blockchain/src/lib.rs
@@ -106,7 +106,7 @@ impl SlotInterval {
             2 => Self::Aggregation,
             3 => Self::SafeTargetUpdate,
             4 => Self::EndOfSlot,
-            _ => unreachable!("slots only have 5 intervals"),
+            _ => unreachable!("slots only have {INTERVALS_PER_SLOT} intervals"),
         }
     }