diff --git a/.efrocachemap b/.efrocachemap
index 66ef75a7..c1d409b4 100644
--- a/.efrocachemap
+++ b/.efrocachemap
@@ -4114,10 +4114,10 @@
   "assets/build/windows/x64/python.exe": "https://files.ballistica.net/cache/ba1/25/a7/dc87c1be41605eb6fefd0145144c",
   "assets/build/windows/x64/python37.dll": "https://files.ballistica.net/cache/ba1/b9/e4/d912f56e42e9991bcbb4c804cfcb",
   "assets/build/windows/x64/pythonw.exe": "https://files.ballistica.net/cache/ba1/6c/bb/b6f52c306aa4e88061510e96cefe",
-  "build/prefab/linux/debug/ballisticacore": "https://files.ballistica.net/cache/ba1/cf/90/b42e63ad9ca244edb663844bfce3",
-  "build/prefab/linux/release/ballisticacore": "https://files.ballistica.net/cache/ba1/09/67/e84435a08b118a555e2aee2055b4",
-  "build/prefab/mac/debug/ballisticacore": "https://files.ballistica.net/cache/ba1/3d/89/954036cad327b2c314dabf3d7185",
-  "build/prefab/mac/release/ballisticacore": "https://files.ballistica.net/cache/ba1/48/77/a578ba55af08d3487e89ee56f704",
-  "build/prefab/windows/debug/BallisticaCore.exe": "https://files.ballistica.net/cache/ba1/23/0e/21f7537dd2cf1d6c2d84e6f93bfe",
-  "build/prefab/windows/release/BallisticaCore.exe": "https://files.ballistica.net/cache/ba1/cd/59/85df0d2b1fad606a0e1138365245"
+  "build/prefab/linux/debug/ballisticacore": "https://files.ballistica.net/cache/ba1/85/4e/8e17f105c42bd7c399f4f60c43b3",
+  "build/prefab/linux/release/ballisticacore": "https://files.ballistica.net/cache/ba1/eb/b5/3a5b133d3a1d5a3de35fd3cfbbbc",
+  "build/prefab/mac/debug/ballisticacore": "https://files.ballistica.net/cache/ba1/de/ce/80e52a4d428d8500a2095d6ce470",
+  "build/prefab/mac/release/ballisticacore": "https://files.ballistica.net/cache/ba1/28/15/aecd6c5dd487f607e47da088bee2",
+  "build/prefab/windows/debug/BallisticaCore.exe": "https://files.ballistica.net/cache/ba1/c6/78/f6383a7b421ecaac09d5cfd02107",
+  "build/prefab/windows/release/BallisticaCore.exe": "https://files.ballistica.net/cache/ba1/cf/7e/aa37853a635b2b89ea32f98db407"
 }
\ No newline at end of file
diff --git a/docs/ba_module.md b/docs/ba_module.md
index 37a18cf8..42ce6af6 100644
--- a/docs/ba_module.md
+++ b/docs/ba_module.md
@@ -4270,7 +4270,7 @@ session.set_activity(foo) and then <a href="#function_ba_newnode">ba.newnode</a>
 
 </dd>
 <dt><h4><a name="method_ba_Stats__set_activity">set_activity()</a></dt></h4><dd>
-<p><span>set_activity(self, activity: <a href="#class_ba_Activity">ba.Activity</a>) -&gt; None</span></p>
+<p><span>set_activity(self, activity: Optional[<a href="#class_ba_Activity">ba.Activity</a>]) -&gt; None</span></p>
 
 <p>Set the current activity for this instance.</p>