diff --git a/00-introduction/solution.ts b/00-introduction/solution.ts
index e9eb2d6..6f1b55f 100644
--- a/00-introduction/solution.ts
+++ b/00-introduction/solution.ts
@@ -5,7 +5,7 @@ import { Equal, Expect } from "../helpers";
 /**
  * 0. Warmup, try assigning "World" to `type Hello`.
  */
- namespace zero {
+namespace zero {
   type Hello = "World";
 
   type test1 = Expect<Equal<Hello, "World">>;