diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index a5707917..95afe409 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -4,7 +4,7 @@ on:
   merge_group:
 
 env:
-  MDBOOK_VERSION: 0.4.40
+  MDBOOK_VERSION: 0.5.1
 
 jobs:
   test:
diff --git a/README.md b/README.md
index 3f399438..48d60f06 100644
--- a/README.md
+++ b/README.md
@@ -17,12 +17,12 @@ You can also build the book and read it locally if you'd like.
 
 ### Requirements
 
-Building the book requires [mdBook] 0.4. To get it:
+Building the book requires [mdBook] 0.5. To get it:
 
 [mdBook]: https://github.com/rust-lang/mdBook
 
 ```bash
-$ cargo install mdbook
+$ cargo install mdbook@^0.5
 ```
 
 ### Building