diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 72670a3..8db37a0 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -35,6 +35,7 @@ jobs:
           - cross
           - sccache
           - mdbook
+          - mdbook-epub
           - wasm-pack
           - wasm-bindgen-cli
           - grcov