diff --git a/devshells/markdown.nix b/devshells/markdown.nix
index 8fcaa55..d0757ab 100644
--- a/devshells/markdown.nix
+++ b/devshells/markdown.nix
@@ -16,6 +16,7 @@
           with ps; [
             mdformat
             mdformat-gfm
+            mdformat-gfm-alerts
             mdformat-tables
             mdformat-footnote
             pygments