diff --git a/l4d2web/l4d2web/templates/overlay_file_editor.html b/l4d2web/l4d2web/templates/overlay_file_editor.html
new file mode 100644
index 0000000..1b00c80
--- /dev/null
+++ b/l4d2web/l4d2web/templates/overlay_file_editor.html
@@ -0,0 +1,47 @@
+{% extends base_layout %}
+{% block title %}Edit {{ rel_path }} · {{ overlay.name }}{% endblock %}
+{% block extra_head %}{% include "_editor_assets.html" %}{% endblock %}
+{% block content %}
+<dialog id="files-editor-modal" class="modal modal-wide" open aria-labelledby="files-editor-title">
+  <div class="modal-header">
+    <h2 id="files-editor-title" class="files-editor-path">
+      <span class="files-editor-title-text">{{ rel_path }}</span>
+    </h2>
+    <button type="button" class="modal-close" data-modal-dismiss aria-label="Close">&times;</button>
+  </div>
+  <div class="modal-body">
+    <label class="files-editor-field">
+      <span class="files-field-label">Filename</span>
+      <input type="text" class="files-editor-filename" data-editor-filename autocomplete="off" spellcheck="false" value="{{ rel_path }}">
+    </label>
+    <p class="files-editor-rename-hint" hidden>↻ Save will rename <code class="files-rename-from"></code> → <code class="files-rename-to"></code>.</p>
+
+    <div class="files-editor-text">
+      <label class="files-editor-field files-editor-language-field">
+        <span class="files-field-label">Language</span>
+        <select data-editor-language-select aria-label="Editor language">
+          <option value="auto">auto (from filename)</option>
+          <option value="srccfg">srccfg (.cfg)</option>
+          <option value="bash">bash (.sh)</option>
+          <option value="plain">plain</option>
+        </select>
+      </label>
+      <label class="files-editor-field">
+        <span class="files-field-label">Content</span>
+        <div class="editor-mount" style="--editor-rows: 14"><textarea class="files-editor-content" rows="14" spellcheck="false" data-editor-language="auto" data-overlay-id="{{ overlay.id }}" data-rel-path="{{ rel_path }}">{{ content }}</textarea></div>
+      </label>
+      <div class="files-editor-meta muted">
+        <span class="files-editor-byte-count">UTF-8 · {{ byte_count }} bytes</span>
+        <span>Ctrl+S to save</span>
+      </div>
+    </div>
+  </div>
+  <div class="modal-footer files-editor-footer">
+    <button type="button" class="danger-outline files-editor-delete">Delete</button>
+    <span class="files-editor-footer-spacer"></span>
+    <a class="button-secondary files-editor-download" href="/overlays/{{ overlay.id }}/files/download?path={{ rel_path|urlencode }}">⬇ Download</a>
+    <button type="button" class="button-secondary" data-modal-dismiss>Cancel</button>
+    <button type="button" class="files-editor-save">Save</button>
+  </div>
+</dialog>
+{% endblock %}