diff --git a/Toolkit.js.scala b/Toolkit.js.scala
index 67fc662..7060e7b 100644
--- a/Toolkit.js.scala
+++ b/Toolkit.js.scala
@@ -1,6 +1,6 @@
 //> using scala "2.13", "2.12", "3"
 
-//> using lib "com.softwaremill.sttp.client3::core::3.8.7"
-//> using lib "com.softwaremill.sttp.client3::upickle::3.8.7"
+//> using lib "com.softwaremill.sttp.client4::core::4.0.0-M1"
+//> using lib "com.softwaremill.sttp.client4::upickle::4.0.0-M1"
 //> using lib "com.lihaoyi::upickle::2.0.0"
 //> using lib "org.scalameta::munit::1.0.0-M7"
diff --git a/Toolkit.scala b/Toolkit.scala
index 8633dda..591e2c6 100644
--- a/Toolkit.scala
+++ b/Toolkit.scala
@@ -1,7 +1,7 @@
 //> using scala "2.13", "2.12", "3"
 
-//> using lib "com.softwaremill.sttp.client3::core::3.8.7"
-//> using lib "com.softwaremill.sttp.client3::upickle::3.8.7"
+//> using lib "com.softwaremill.sttp.client4::core::4.0.0-M1"
+//> using lib "com.softwaremill.sttp.client4::upickle::4.0.0-M1"
 //> using lib "com.lihaoyi::upickle::2.0.0"
 //> using lib "com.lihaoyi::os-lib::0.9.0"
 //> using lib "org.scalameta::munit::1.0.0-M7"