diff --git a/setup_linux.sh b/setup_linux.sh
index 87118146..38d97ba0 100755
--- a/setup_linux.sh
+++ b/setup_linux.sh
@@ -1,6 +1,11 @@
 #!/bin/bash
 SCRIPTDIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" >/dev/null 2>&1 && pwd )"
 
+if [[ "$(uname)" != "Linux" ]]; then 
+    echo Not running Linux
+    exit 1
+fi
+
 if [ "$(lsb_release -d | grep -qEi 'debian|buntu|mint')" ]; then
     echo Not a supported Linux
     exit 1
diff --git a/veilid-flutter/example/lib/app.dart b/veilid-flutter/example/lib/app.dart
index f630303d..3c9e7fbb 100644
--- a/veilid-flutter/example/lib/app.dart
+++ b/veilid-flutter/example/lib/app.dart
@@ -167,6 +167,9 @@ class _MyAppState extends State<MyApp> with UiLoggy {
                     },
                     onSubmitted: (String v) async {
                       try {
+                        if (v.isEmpty) {
+                          return;
+                        }
                         var res = await Veilid.instance.debug(v);
                         loggy.info(res);
                         setState(() {
diff --git a/veilid-wasm/wasm_build.sh b/veilid-wasm/wasm_build.sh
index 9aa3cbf8..093bbcc1 100755
--- a/veilid-wasm/wasm_build.sh
+++ b/veilid-wasm/wasm_build.sh
@@ -1,6 +1,13 @@
 #!/bin/bash
 SCRIPTDIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" >/dev/null 2>&1 && pwd )"
 
+set -eo pipefail
+
+get_abs_filename() {
+    # $1 : relative filename
+    echo "$(cd "$(dirname "$1")" && pwd)/$(basename "$1")"
+}
+
 pushd $SCRIPTDIR &> /dev/null
 
 if [ -f /usr/local/opt/llvm/bin/llvm-dwarfdump ]; then
@@ -15,7 +22,15 @@ else
 fi
 
 
-if [[ "$1" == "debug" ]]; then  
+if [[ "$1" == "release" ]]; then  
+    OUTPUTDIR=../target/wasm32-unknown-unknown/release/pkg
+    INPUTDIR=../target/wasm32-unknown-unknown/release
+
+    cargo build --target wasm32-unknown-unknown --release
+    mkdir -p $OUTPUTDIR
+    wasm-bindgen --out-dir $OUTPUTDIR --target web --no-typescript $INPUTDIR/veilid_wasm.wasm
+    wasm-strip $OUTPUTDIR/veilid_wasm_bg.wasm
+else
     OUTPUTDIR=../target/wasm32-unknown-unknown/debug/pkg
     INPUTDIR=../target/wasm32-unknown-unknown/debug
 
@@ -24,14 +39,9 @@ if [[ "$1" == "debug" ]]; then
     wasm-bindgen --out-dir $OUTPUTDIR --target web --no-typescript --keep-debug --debug $INPUTDIR/veilid_wasm.wasm
     ./wasm-sourcemap.py $OUTPUTDIR/veilid_wasm_bg.wasm -o $OUTPUTDIR/veilid_wasm_bg.wasm.map --dwarfdump $DWARFDUMP
     # wasm-strip $OUTPUTDIR/veilid_wasm_bg.wasm
-else
-    OUTPUTDIR=../target/wasm32-unknown-unknown/release/pkg
-    INPUTDIR=../target/wasm32-unknown-unknown/release
-
-    cargo build --target wasm32-unknown-unknown --release
-    mkdir -p $OUTPUTDIR
-    wasm-bindgen --out-dir $OUTPUTDIR --target web --no-typescript $INPUTDIR/veilid_wasm.wasm
-    wasm-strip $OUTPUTDIR/veilid_wasm_bg.wasm
 fi
 
 popd &> /dev/null
+
+# Print for use with scripts
+echo SUCCESS:OUTPUTDIR=$(get_abs_filename $OUTPUTDIR)
\ No newline at end of file