diff --git a/packages/codemirror/slider.mjs b/packages/codemirror/slider.mjs
index 159e4fd1..47b686c8 100644
--- a/packages/codemirror/slider.mjs
+++ b/packages/codemirror/slider.mjs
@@ -1,4 +1,4 @@
-import { ref } from '@strudel.cycles/core';
+import { ref, pure } from '@strudel.cycles/core';
 import { WidgetType, ViewPlugin, Decoration } from '@codemirror/view';
 import { StateEffect, StateField } from '@codemirror/state';