diff --git a/src/build.sh b/src/build.sh
index 6d1b7db..928867a 100644
--- a/src/build.sh
+++ b/src/build.sh
@@ -2,8 +2,9 @@
 #! nix-shell -i bash --pure
 #! nix-shell -p bash curl gcc zlib libffi icu77
 VERSION="140.4.0esr"
-DOWNLOAD="https://ftp.mozilla.org/pub/firefox/releases/$VERSION/source/firefox-$VERSION.source.tar.xz/"
+DOWNLOAD="https://ftp.mozilla.org/pub/firefox/releases/$VERSION/source/firefox-$VERSION.source.tar.xz"
 BUILDPATH=$(realpath .)
+mkdir bin
 
 #debug stuff
 echo $VERSION
@@ -21,7 +22,7 @@ cd "src/js/src"
 mkdir _build
 cd _build
 
-../configure --disable-jemalloc --with-system-zlib --with-system-icu --prefix=$BUILDPATH \
+../configure --disable-jemalloc --with-system-zlib --with-system-icu --prefix="$BUILDPATH/bin" \
     --with-intl-api --enable-optimize
 
 make