diff --git a/R/shinyModule.R b/R/shinyModule.R
index 830dd1f..2e9af29 100644
--- a/R/shinyModule.R
+++ b/R/shinyModule.R
@@ -135,7 +135,7 @@ shiny_version_required <- function() {
 test_shiny_version <- function() {
   tryCatch({
     utils::packageVersion("shiny") >= shiny_version_required()
-  }, error = function() {
+  }, error = function(e) {
     # package not found
     FALSE
   })
diff --git a/bin/postinstall.sh b/bin/postinstall.sh
index 6c14877..37dab33 100755
--- a/bin/postinstall.sh
+++ b/bin/postinstall.sh
@@ -2,6 +2,6 @@
 
 # do not create stubs from missing libraries
 # ignore dev dependencies
-yarn flow-typed install --skip true --ignoreDeps dev
+yarn flow-typed install --skip true --ignoreDeps dev || true
 
 yarn build-only