diff --git a/src/static-guarantees/design-contracts.md b/src/static-guarantees/design-contracts.md
index ea3eae6..f0df219 100644
--- a/src/static-guarantees/design-contracts.md
+++ b/src/static-guarantees/design-contracts.md
@@ -97,7 +97,7 @@ impl Gpio {
 }
 ```
 
-Because we need to enforce the restrictions on the hardware, we end up doing a lot of runtime checking whch wastes time and resources, and this code will be much less pleasant for the developer to use.
+Because we need to enforce the restrictions on the hardware, we end up doing a lot of runtime checking which wastes time and resources, and this code will be much less pleasant for the developer to use.
 
 ## Type States