diff --git a/build.sh b/build.sh
index ac08c4c..0cc9f97 100755
--- a/build.sh
+++ b/build.sh
@@ -1,3 +1,5 @@
+#!/bin/bash
+set +x
 pandoc --listings doc.md -o doc.tex
 pdflatex -interaction=nonstopmode main.tex
 
@@ -5,26 +7,28 @@ pdflatex -interaction=nonstopmode main.tex
 pages=$(pdfinfo main.pdf | awk '/^Pages:/ {print $2}')
 
 # split cover from guts to add correct signature
-pdfjam main.pdf 1,$(($pages))-$pages -o cover.pdf
+pdfjam main.pdf 1,$((pages)) -o cover.pdf
 pdfjam main.pdf 2-$((pages-1)) -o guts.pdf
 
-# insert blank pages after front cover and before back cover
+# # insert blank pages after front cover and before back cover
 pdfjam cover.pdf '1,{},{},2' --outfile cover.pdf
 
 # calculate pages for guts signature length
-pages=$(pdfinfo guts.pdf | awk '/^Pages:/ {print $2}')
-let rem=pages%4
-let extra=(4-rem)%4
-let sig=pages+extra
+pages="$(pdfinfo guts.pdf | awk '/^Pages:/ {print $2}')"
+rem=$((pages%4))
+extra=$((4-rem%4))
+sig=$((pages+extra))
 
 # booklet print
-pdfbook2 -n --short-edge cover.pdf
-pdfbook2 -n --signature=$sig --short-edge guts.pdf
+pdfbook2 -n cover.pdf
+pdfbook2 -n --signature="$sig" guts.pdf
+# pdfbook2 -n --short-edge cover.pdf
+# pdfbook2 -n --signature="$sig" --short-edge guts.pdf
 
 # put them back together!
 pdfunite cover-book.pdf guts-book.pdf print-zine.pdf
 mv main.pdf read-zine.pdf
 
 # directory cleanup
-mv -t .build *.aux *.log *.out doc.tex cover.pdf guts.pdf cover-book.pdf guts-book.pdf
+mv -t .build ./*.aux ./*.log ./*.out doc.tex cover.pdf guts.pdf cover-book.pdf guts-book.pdf