diff --git a/src/bundles/csg/package.json b/src/bundles/csg/package.json
index 65ee3d01a..b7bf25e04 100644
--- a/src/bundles/csg/package.json
+++ b/src/bundles/csg/package.json
@@ -5,7 +5,7 @@
   "dependencies": {
     "@jscad/modeling": "patch:@jscad/modeling@npm%3A2.9.6#~/.yarn/patches/@jscad-modeling-npm-2.9.6-71e6aa3a91.patch",
     "@jscad/regl-renderer": "^2.6.1",
-    "@jscad/stl-serializer": "2.1.11",
+    "@jscad/stl-serializer": "2.1.21",
     "@sourceacademy/modules-lib": "workspace:^",
     "save-file": "^2.3.1"
   },
diff --git a/yarn.lock b/yarn.lock
index dd7c5262d..6291bf443 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -2919,6 +2919,13 @@ __metadata:
   languageName: node
   linkType: hard
 
+"@jscad/modeling@npm:2.12.6":
+  version: 2.12.6
+  resolution: "@jscad/modeling@npm:2.12.6"
+  checksum: 10c0/13d3be7fbb41767fd38930bf017b508844cacc767b23020adead18a6667dbe76b55ae235df2144783a5345bfe9791cb8ff6b9fd6fd3d9d0d5f320146c5149abc
+  languageName: node
+  linkType: hard
+
 "@jscad/modeling@npm:2.9.6":
   version: 2.9.6
   resolution: "@jscad/modeling@npm:2.9.6"
@@ -2946,13 +2953,13 @@ __metadata:
   languageName: node
   linkType: hard
 
-"@jscad/stl-serializer@npm:2.1.11":
-  version: 2.1.11
-  resolution: "@jscad/stl-serializer@npm:2.1.11"
+"@jscad/stl-serializer@npm:2.1.21":
+  version: 2.1.21
+  resolution: "@jscad/stl-serializer@npm:2.1.21"
   dependencies:
     "@jscad/array-utils": "npm:2.1.4"
-    "@jscad/modeling": "npm:2.9.6"
-  checksum: 10c0/6835b58077a20e74a05a300c9d0cf1fe3b8879cccd64fe64b1626e12d1aa261866c11c173d1020a4125ef9d1a0aee0c803401010ee9e9dbb2c9137c65e2c95b8
+    "@jscad/modeling": "npm:2.12.6"
+  checksum: 10c0/57b9a26d73332719f0ef3976da367b6d6589654de16ea7c49adbdf3928563a12a16acb9ab60aff1e2f39124ad6aee7c3050e0c8db403905f756e4a38c7bede46
   languageName: node
   linkType: hard
 
@@ -4105,7 +4112,7 @@ __metadata:
   dependencies:
     "@jscad/modeling": "patch:@jscad/modeling@npm%3A2.9.6#~/.yarn/patches/@jscad-modeling-npm-2.9.6-71e6aa3a91.patch"
     "@jscad/regl-renderer": "npm:^2.6.1"
-    "@jscad/stl-serializer": "npm:2.1.11"
+    "@jscad/stl-serializer": "npm:2.1.21"
     "@sourceacademy/modules-buildtools": "workspace:^"
     "@sourceacademy/modules-lib": "workspace:^"
     save-file: "npm:^2.3.1"