diff --git a/script/fetch-emscripten b/script/fetch-emscripten
index 14d526d9..f8b96acc 100755
--- a/script/fetch-emscripten
+++ b/script/fetch-emscripten
@@ -2,6 +2,8 @@
 
 set -e
 
+EMSCRIPTEN_VERSION=1.38.40
+
 mkdir -p target
 EMSDK_DIR="./target/emsdk"
 
@@ -19,10 +21,10 @@ EMSDK_DIR="./target/emsdk"
   ./emsdk list
 
   echo 'Installing latest emscripten...'
-  ./emsdk install latest
+  ./emsdk install $EMSCRIPTEN_VERSION
 
   echo 'Activating latest emscripten...'
-  ./emsdk activate latest
+  ./emsdk activate $EMSCRIPTEN_VERSION
 ) >&2
 
 (