diff --git a/changelog.md b/changelog.md
--- a/changelog.md
+++ b/changelog.md
@@ -1,5 +1,9 @@
 # Changelog for commonmark-extensions
 
+## 0.2.5.1
+
+  * Add `test/alerts.md` to extra-source-files in cabal file.
+
 ## 0.2.5
 
   * Add support for alerts extension, supporting GitHub-style alerts (#132).
diff --git a/commonmark-extensions.cabal b/commonmark-extensions.cabal
--- a/commonmark-extensions.cabal
+++ b/commonmark-extensions.cabal
@@ -1,5 +1,5 @@
 name:           commonmark-extensions
-version:        0.2.5
+version:        0.2.5.1
 synopsis:       Pure Haskell commonmark parser.
 description:
    This library provides some useful extensions to core commonmark
@@ -22,6 +22,7 @@
     README.md
     test/definition_lists.md
     test/fancy_lists.md
+    test/alerts.md
     test/autolinks.md
     test/auto_identifiers.md
     test/auto_identifiers_ascii.md
diff --git a/test/alerts.md b/test/alerts.md
new file mode 100644
--- /dev/null
+++ b/test/alerts.md
@@ -0,0 +1,128 @@
+## Alerts
+
+GitHub style alerts look like this:
+
+```````````````````````````````` example
+> [!NOTE]
+> Highlights information that users should take into account, even when skimming.
+.
+<div class="alert alert-note">
+<p class="alert-title">
+<svg viewBox="0 0 16 16" width="16" height="16" aria-hidden="true">
+<path d="M0 8a8 8 0 1 1 16 0A8 8 0 0 1 0 8Zm8-6.5a6.5 6.5 0 1 0 0 13 6.5 6.5 0 0 0 0-13ZM6.5 7.75A.75.75 0 0 1 7.25 7h1a.75.75 0 0 1 .75.75v2.75h.25a.75.75 0 0 1 0 1.5h-2a.75.75 0 0 1 0-1.5h.25v-2h-.25a.75.75 0 0 1-.75-.75ZM8 6a1 1 0 1 1 0-2 1 1 0 0 1 0 2Z"></path>
+</svg>
+Note</p>
+<p>Highlights information that users should take into account, even when skimming.</p>
+</div>
+````````````````````````````````
+
+It shouldn't matter if there's a soft break or hard break after
+the `[!NOTE]`:
+
+```````````````````````````````` example
+> [!NOTE]  
+> Highlights information that users should take into account, even when skimming.
+.
+<div class="alert alert-note">
+<p class="alert-title">
+<svg viewBox="0 0 16 16" width="16" height="16" aria-hidden="true">
+<path d="M0 8a8 8 0 1 1 16 0A8 8 0 0 1 0 8Zm8-6.5a6.5 6.5 0 1 0 0 13 6.5 6.5 0 0 0 0-13ZM6.5 7.75A.75.75 0 0 1 7.25 7h1a.75.75 0 0 1 .75.75v2.75h.25a.75.75 0 0 1 0 1.5h-2a.75.75 0 0 1 0-1.5h.25v-2h-.25a.75.75 0 0 1-.75-.75ZM8 6a1 1 0 1 1 0-2 1 1 0 0 1 0 2Z"></path>
+</svg>
+Note</p>
+<p>Highlights information that users should take into account, even when skimming.</p>
+</div>
+````````````````````````````````
+
+Uppercase isn't required:
+
+```````````````````````````````` example
+> [!note]
+> Highlights information that users should take into account, even when skimming.
+.
+<div class="alert alert-note">
+<p class="alert-title">
+<svg viewBox="0 0 16 16" width="16" height="16" aria-hidden="true">
+<path d="M0 8a8 8 0 1 1 16 0A8 8 0 0 1 0 8Zm8-6.5a6.5 6.5 0 1 0 0 13 6.5 6.5 0 0 0 0-13ZM6.5 7.75A.75.75 0 0 1 7.25 7h1a.75.75 0 0 1 .75.75v2.75h.25a.75.75 0 0 1 0 1.5h-2a.75.75 0 0 1 0-1.5h.25v-2h-.25a.75.75 0 0 1-.75-.75ZM8 6a1 1 0 1 1 0-2 1 1 0 0 1 0 2Z"></path>
+</svg>
+Note</p>
+<p>Highlights information that users should take into account, even when skimming.</p>
+</div>
+````````````````````````````````
+
+
+Alerts can contain multiple blocks:
+
+```````````````````````````````` example
+> [!NOTE]
+> Highlights information that users should take into account, even when skimming.
+>
+> Paragraph two.
+.
+<div class="alert alert-note">
+<p class="alert-title">
+<svg viewBox="0 0 16 16" width="16" height="16" aria-hidden="true">
+<path d="M0 8a8 8 0 1 1 16 0A8 8 0 0 1 0 8Zm8-6.5a6.5 6.5 0 1 0 0 13 6.5 6.5 0 0 0 0-13ZM6.5 7.75A.75.75 0 0 1 7.25 7h1a.75.75 0 0 1 .75.75v2.75h.25a.75.75 0 0 1 0 1.5h-2a.75.75 0 0 1 0-1.5h.25v-2h-.25a.75.75 0 0 1-.75-.75ZM8 6a1 1 0 1 1 0-2 1 1 0 0 1 0 2Z"></path>
+</svg>
+Note</p>
+<p>Highlights information that users should take into account, even when skimming.</p>
+<p>Paragraph two.</p>
+</div>
+````````````````````````````````
+
+Other kinds of alerts:
+
+```````````````````````````````` example
+> [!TIP]
+> Optional information to help a user be more successful.
+.
+<div class="alert alert-tip">
+<p class="alert-title">
+<svg viewBox="0 0 16 16" width="16" height="16" aria-hidden="true">
+<path d="M8 1.5c-2.363 0-4 1.69-4 3.75 0 .984.424 1.625.984 2.304l.214.253c.223.264.47.556.673.848.284.411.537.896.621 1.49a.75.75 0 0 1-1.484.211c-.04-.282-.163-.547-.37-.847a8.456 8.456 0 0 0-.542-.68c-.084-.1-.173-.205-.268-.32C3.201 7.75 2.5 6.766 2.5 5.25 2.5 2.31 4.863 0 8 0s5.5 2.31 5.5 5.25c0 1.516-.701 2.5-1.328 3.259-.095.115-.184.22-.268.319-.207.245-.383.453-.541.681-.208.3-.33.565-.37.847a.751.751 0 0 1-1.485-.212c.084-.593.337-1.078.621-1.489.203-.292.45-.584.673-.848.075-.088.147-.173.213-.253.561-.679.985-1.32.985-2.304 0-2.06-1.637-3.75-4-3.75ZM5.75 12h4.5a.75.75 0 0 1 0 1.5h-4.5a.75.75 0 0 1 0-1.5ZM6 15.25a.75.75 0 0 1 .75-.75h2.5a.75.75 0 0 1 0 1.5h-2.5a.75.75 0 0 1-.75-.75Z"></path>
+</svg>
+Tip</p>
+<p>Optional information to help a user be more successful.</p>
+</div>
+````````````````````````````````
+
+```````````````````````````````` example
+> [!IMPORTANT]
+> Crucial information necessary for users to succeed.
+.
+<div class="alert alert-important">
+<p class="alert-title">
+<svg viewBox="0 0 16 16" width="16" height="16" aria-hidden="true">
+<path d="M0 1.75C0 .784.784 0 1.75 0h12.5C15.216 0 16 .784 16 1.75v9.5A1.75 1.75 0 0 1 14.25 13H8.06l-2.573 2.573A1.458 1.458 0 0 1 3 14.543V13H1.75A1.75 1.75 0 0 1 0 11.25Zm1.75-.25a.25.25 0 0 0-.25.25v9.5c0 .138.112.25.25.25h2a.75.75 0 0 1 .75.75v2.19l2.72-2.72a.749.749 0 0 1 .53-.22h6.5a.25.25 0 0 0 .25-.25v-9.5a.25.25 0 0 0-.25-.25Zm7 2.25v2.5a.75.75 0 0 1-1.5 0v-2.5a.75.75 0 0 1 1.5 0ZM9 9a1 1 0 1 1-2 0 1 1 0 0 1 2 0Z"></path>
+</svg>
+Important</p>
+<p>Crucial information necessary for users to succeed.</p>
+</div>
+````````````````````````````````
+
+```````````````````````````````` example
+> [!WARNING]
+> Critical content demanding immediate user attention due to potential risks.
+.
+<div class="alert alert-warning">
+<p class="alert-title">
+<svg viewBox="0 0 16 16" width="16" height="16" aria-hidden="true">
+<path d="M6.457 1.047c.659-1.234 2.427-1.234 3.086 0l6.082 11.378A1.75 1.75 0 0 1 14.082 15H1.918a1.75 1.75 0 0 1-1.543-2.575Zm1.763.707a.25.25 0 0 0-.44 0L1.698 13.132a.25.25 0 0 0 .22.368h12.164a.25.25 0 0 0 .22-.368Zm.53 3.996v2.5a.75.75 0 0 1-1.5 0v-2.5a.75.75 0 0 1 1.5 0ZM9 11a1 1 0 1 1-2 0 1 1 0 0 1 2 0Z"></path>
+</svg>
+Warning</p>
+<p>Critical content demanding immediate user attention due to potential risks.</p>
+</div>
+````````````````````````````````
+
+```````````````````````````````` example
+> [!CAUTION]
+> Negative potential consequences of an action.
+.
+<div class="alert alert-caution">
+<p class="alert-title">
+<svg viewBox="0 0 16 16" width="16" height="16" aria-hidden="true">
+<path d="M4.47.22A.749.749 0 0 1 5 0h6c.199 0 .389.079.53.22l4.25 4.25c.141.14.22.331.22.53v6a.749.749 0 0 1-.22.53l-4.25 4.25A.749.749 0 0 1 11 16H5a.749.749 0 0 1-.53-.22L.22 11.53A.749.749 0 0 1 0 11V5c0-.199.079-.389.22-.53Zm.84 1.28L1.5 5.31v5.38l3.81 3.81h5.38l3.81-3.81V5.31L10.69 1.5ZM8 4a.75.75 0 0 1 .75.75v3.5a.75.75 0 0 1-1.5 0v-3.5A.75.75 0 0 1 8 4Zm0 8a1 1 0 1 1 0-2 1 1 0 0 1 0 2Z"></path>
+</svg>
+Caution</p>
+<p>Negative potential consequences of an action.</p>
+</div>
+````````````````````````````````
