diff --git a/contrib/devtools/commit-script-check.sh b/contrib/devtools/commit-script-check.sh
index 1c9dbc7f68f..ef72c5e5548 100755
--- a/contrib/devtools/commit-script-check.sh
+++ b/contrib/devtools/commit-script-check.sh
@@ -17,12 +17,12 @@ if test "x$1" = "x"; then
 fi
 
 RET=0
-PREV_BRANCH=`git name-rev --name-only HEAD`
-PREV_HEAD=`git rev-parse HEAD`
-for i in `git rev-list --reverse $1`; do
+PREV_BRANCH=$(git name-rev --name-only HEAD)
+PREV_HEAD=$(git rev-parse HEAD)
+for i in $(git rev-list --reverse $1); do
     if git rev-list -n 1 --pretty="%s" $i | grep -q "^scripted-diff:"; then
         git checkout --quiet $i^ || exit
-        SCRIPT="`git rev-list --format=%b -n1 $i | sed '/^-BEGIN VERIFY SCRIPT-$/,/^-END VERIFY SCRIPT-$/{//!b};d'`"
+        SCRIPT="$(git rev-list --format=%b -n1 $i | sed '/^-BEGIN VERIFY SCRIPT-$/,/^-END VERIFY SCRIPT-$/{//!b};d')"
         if test "x$SCRIPT" = "x"; then
             echo "Error: missing script for: $i"
             echo "Failed"
diff --git a/contrib/devtools/gen-manpages.sh b/contrib/devtools/gen-manpages.sh
index 967717e1e0d..925d6a6252a 100755
--- a/contrib/devtools/gen-manpages.sh
+++ b/contrib/devtools/gen-manpages.sh
@@ -1,4 +1,4 @@
-#!/bin/sh
+#!/bin/bash
 
 TOPDIR=${TOPDIR:-$(git rev-parse --show-toplevel)}
 SRCDIR=${SRCDIR:-$TOPDIR/src}
diff --git a/contrib/gitian-build.sh b/contrib/gitian-build.sh
index 6ee5df47039..64dbbfd1356 100755
--- a/contrib/gitian-build.sh
+++ b/contrib/gitian-build.sh
@@ -106,7 +106,7 @@ while :; do
 		fi
 		shift
 	    else
-		echo 'Error: "--os" requires an argument containing an l (for linux), w (for windows), or x (for Mac OSX)\n'
+		echo 'Error: "--os" requires an argument containing an l (for linux), w (for windows), or x (for Mac OSX)'
 		exit 1
 	    fi
 	    ;;
@@ -191,7 +191,7 @@ then
 fi
 
 # Get signer
-if [[ -n"$1" ]]
+if [[ -n "$1" ]]
 then
     SIGNER=$1
     shift
@@ -266,7 +266,7 @@ then
 	mkdir -p inputs
 	wget -N -P inputs $osslPatchUrl
 	wget -N -P inputs $osslTarUrl
-	make -C ../bitcoin/depends download SOURCES_PATH=`pwd`/cache/common
+	make -C ../bitcoin/depends download SOURCES_PATH="$(pwd)/cache/common"
 
 	# Linux
 	if [[ $linux = true ]]
diff --git a/contrib/macdeploy/detached-sig-apply.sh b/contrib/macdeploy/detached-sig-apply.sh
index 91674a92e6f..7fe15e793b5 100755
--- a/contrib/macdeploy/detached-sig-apply.sh
+++ b/contrib/macdeploy/detached-sig-apply.sh
@@ -35,13 +35,13 @@ if [ -z "${CODESIGN_ALLOCATE}" ]; then
 fi
 
 find ${TEMPDIR} -name "*.sign" | while read i; do
-  SIZE=`stat -c %s "${i}"`
-  TARGET_FILE="`echo "${i}" | sed 's/\.sign$//'`"
+  SIZE=$(stat -c %s "${i}")
+  TARGET_FILE="$(echo "${i}" | sed 's/\.sign$//')"
 
   echo "Allocating space for the signature of size ${SIZE} in ${TARGET_FILE}"
   ${CODESIGN_ALLOCATE} -i "${TARGET_FILE}" -a ${ARCH} ${SIZE} -o "${i}.tmp"
 
-  OFFSET=`${PAGESTUFF} "${i}.tmp" -p | tail -2 | grep offset | sed 's/[^0-9]*//g'`
+  OFFSET=$(${PAGESTUFF} "${i}.tmp" -p | tail -2 | grep offset | sed 's/[^0-9]*//g')
   if [ -z ${QUIET} ]; then
     echo "Attaching signature at offset ${OFFSET}"
   fi
diff --git a/contrib/macdeploy/detached-sig-create.sh b/contrib/macdeploy/detached-sig-create.sh
index 7f017bb4f1c..cbc6612520c 100755
--- a/contrib/macdeploy/detached-sig-create.sh
+++ b/contrib/macdeploy/detached-sig-create.sh
@@ -25,22 +25,22 @@ mkdir -p ${TEMPDIR}
 ${CODESIGN} -f --file-list ${TEMPLIST} "$@" "${BUNDLE}"
 
 grep -v CodeResources < "${TEMPLIST}" | while read i; do
-  TARGETFILE="${BUNDLE}/`echo "${i}" | sed "s|.*${BUNDLE}/||"`"
-  SIZE=`pagestuff "$i" -p | tail -2 | grep size | sed 's/[^0-9]*//g'`
-  OFFSET=`pagestuff "$i" -p | tail -2 | grep offset | sed 's/[^0-9]*//g'`
+  TARGETFILE="${BUNDLE}/$(echo "${i}" | sed "s|.*${BUNDLE}/||")"
+  SIZE=$(pagestuff "$i" -p | tail -2 | grep size | sed 's/[^0-9]*//g')
+  OFFSET=$(pagestuff "$i" -p | tail -2 | grep offset | sed 's/[^0-9]*//g')
   SIGNFILE="${TEMPDIR}/${OUTROOT}/${TARGETFILE}.sign"
-  DIRNAME="`dirname "${SIGNFILE}"`"
+  DIRNAME="$(dirname "${SIGNFILE}")"
   mkdir -p "${DIRNAME}"
   echo "Adding detached signature for: ${TARGETFILE}. Size: ${SIZE}. Offset: ${OFFSET}"
   dd if="$i" of="${SIGNFILE}" bs=1 skip=${OFFSET} count=${SIZE} 2>/dev/null
 done
 
 grep CodeResources < "${TEMPLIST}" | while read i; do
-  TARGETFILE="${BUNDLE}/`echo "${i}" | sed "s|.*${BUNDLE}/||"`"
+  TARGETFILE="${BUNDLE}/$(echo "${i}" | sed "s|.*${BUNDLE}/||")"
   RESOURCE="${TEMPDIR}/${OUTROOT}/${TARGETFILE}"
-  DIRNAME="`dirname "${RESOURCE}"`"
+  DIRNAME="$(dirname "${RESOURCE}")"
   mkdir -p "${DIRNAME}"
-  echo "Adding resource for: "${TARGETFILE}""
+  echo "Adding resource for: \"${TARGETFILE}\""
   cp "${i}" "${RESOURCE}"
 done
 
diff --git a/contrib/tidy_datadir.sh b/contrib/tidy_datadir.sh
index 8960f8811d8..2bc0ee95606 100755
--- a/contrib/tidy_datadir.sh
+++ b/contrib/tidy_datadir.sh
@@ -4,7 +4,7 @@
 # file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 if [ -d "$1" ]; then
-  cd "$1"
+  cd "$1" || exit 1
 else
   echo "Usage: $0 <datadir>" >&2
   echo "Removes obsolete Bitcoin database files" >&2
@@ -12,10 +12,10 @@ else
 fi
 
 LEVEL=0
-if [ -f wallet.dat -a -f addr.dat -a -f blkindex.dat -a -f blk0001.dat ]; then LEVEL=1; fi
-if [ -f wallet.dat -a -f peers.dat -a -f blkindex.dat -a -f blk0001.dat ]; then LEVEL=2; fi
-if [ -f wallet.dat -a -f peers.dat -a -f coins/CURRENT -a -f blktree/CURRENT -a -f blocks/blk00000.dat ]; then LEVEL=3; fi
-if [ -f wallet.dat -a -f peers.dat -a -f chainstate/CURRENT -a -f blocks/index/CURRENT -a -f blocks/blk00000.dat ]; then LEVEL=4; fi
+if [ -f wallet.dat ] && [ -f addr.dat ] && [ -f blkindex.dat ] && [ -f blk0001.dat ]; then LEVEL=1; fi
+if [ -f wallet.dat ] && [ -f peers.dat ] && [ -f blkindex.dat ] && [ -f blk0001.dat ]; then LEVEL=2; fi
+if [ -f wallet.dat ] && [ -f peers.dat ] && [ -f coins/CURRENT ] && [ -f blktree/CURRENT ] && [ -f blocks/blk00000.dat ]; then LEVEL=3; fi
+if [ -f wallet.dat ] && [ -f peers.dat ] && [ -f chainstate/CURRENT ] && [ -f blocks/index/CURRENT ] && [ -f blocks/blk00000.dat ]; then LEVEL=4; fi
 
 case $LEVEL in
   0)
diff --git a/contrib/verify-commits/verify-commits.sh b/contrib/verify-commits/verify-commits.sh
index 74b7f38375a..daebe2cdd4a 100755
--- a/contrib/verify-commits/verify-commits.sh
+++ b/contrib/verify-commits/verify-commits.sh
@@ -38,8 +38,8 @@ PREV_COMMIT=""
 
 while true; do
 	if [ "$CURRENT_COMMIT" = $VERIFIED_ROOT ]; then
-		echo "There is a valid path from "$CURRENT_COMMIT" to $VERIFIED_ROOT where all commits are signed!"
-		exit 0;
+		echo "There is a valid path from \"$CURRENT_COMMIT\" to $VERIFIED_ROOT where all commits are signed!"
+		exit 0
 	fi
 
 	if [ "$CURRENT_COMMIT" = $VERIFIED_SHA512_ROOT ]; then
@@ -77,7 +77,7 @@ while true; do
 	fi
 
 	# We always verify the top of the tree
-	if [ "$VERIFY_TREE" = 1 -o "$PREV_COMMIT" = "" ]; then
+	if [ "$VERIFY_TREE" = 1 ] || [ "$PREV_COMMIT" = "" ]; then
 		IFS_CACHE="$IFS"
 		IFS='
 '
diff --git a/contrib/verifybinaries/verify.sh b/contrib/verifybinaries/verify.sh
index c2cc2b7013a..160f0460356 100755
--- a/contrib/verifybinaries/verify.sh
+++ b/contrib/verifybinaries/verify.sh
@@ -30,7 +30,7 @@ if [ ! -d "$WORKINGDIR" ]; then
    mkdir "$WORKINGDIR"
 fi
 
-cd "$WORKINGDIR"
+cd "$WORKINGDIR" || exit 1
 
 #test if a version number has been passed as an argument
 if [ -n "$1" ]; then
@@ -86,7 +86,7 @@ WGETOUT=$(wget -N "$BASEDIR$SIGNATUREFILENAME" 2>&1)
 #and then see if wget completed successfully
 if [ $? -ne 0 ]; then
    echo "Error: couldn't fetch signature file. Have you specified the version number in the following format?"
-   echo "[$VERSIONPREFIX]<version>-[$RCVERSIONSTRING[0-9]] (example: "$VERSIONPREFIX"0.10.4-"$RCVERSIONSTRING"1)"
+   echo "[$VERSIONPREFIX]<version>-[$RCVERSIONSTRING[0-9]] (example: ${VERSIONPREFIX}0.10.4-${RCVERSIONSTRING}1)"
    echo "wget output:"
    echo "$WGETOUT"|sed 's/^/\t/g'
    exit 2
diff --git a/contrib/windeploy/detached-sig-create.sh b/contrib/windeploy/detached-sig-create.sh
index bf4978d1430..b0c48385189 100755
--- a/contrib/windeploy/detached-sig-create.sh
+++ b/contrib/windeploy/detached-sig-create.sh
@@ -22,7 +22,7 @@ TIMESERVER=http://timestamp.comodoca.com
 CERTFILE="win-codesign.cert"
 
 mkdir -p "${OUTSUBDIR}"
-basename -a `ls -1 "${SRCDIR}"/*-unsigned.exe` | while read UNSIGNED; do
+basename -a $(ls -1 "${SRCDIR}"/*-unsigned.exe) | while read UNSIGNED; do
   echo Signing "${UNSIGNED}"
   "${OSSLSIGNCODE}" sign -certs "${CERTFILE}" -t "${TIMESERVER}" -in "${SRCDIR}/${UNSIGNED}" -out "${WORKDIR}/${UNSIGNED}" "$@"
   "${OSSLSIGNCODE}" extract-signature -pem -in "${WORKDIR}/${UNSIGNED}" -out "${OUTSUBDIR}/${UNSIGNED}.pem" && rm "${WORKDIR}/${UNSIGNED}"
diff --git a/share/genbuild.sh b/share/genbuild.sh
index 32ef2a5755a..540bdc55af8 100755
--- a/share/genbuild.sh
+++ b/share/genbuild.sh
@@ -4,7 +4,7 @@
 # file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 if [ $# -gt 1 ]; then
-    cd "$2"
+    cd "$2" || exit 1
 fi
 if [ $# -gt 0 ]; then
     FILE="$1"
@@ -23,7 +23,7 @@ git_check_in_repo() {
 
 DESC=""
 SUFFIX=""
-if [ "${BITCOIN_GENBUILD_NO_GIT}" != "1" -a -e "$(which git 2>/dev/null)" -a "$(git rev-parse --is-inside-work-tree 2>/dev/null)" = "true" ] && git_check_in_repo share/genbuild.sh; then
+if [ "${BITCOIN_GENBUILD_NO_GIT}" != "1" ] && [ -e "$(which git 2>/dev/null)" ] && [ "$(git rev-parse --is-inside-work-tree 2>/dev/null)" = "true" ] && git_check_in_repo share/genbuild.sh; then
     # clean 'dirty' status of touched files that haven't been modified
     git diff >/dev/null 2>/dev/null 
 
diff --git a/src/qt/res/movies/makespinner.sh b/src/qt/res/movies/makespinner.sh
index d0deb1238c2..538b0daeb82 100755
--- a/src/qt/res/movies/makespinner.sh
+++ b/src/qt/res/movies/makespinner.sh
@@ -6,6 +6,6 @@ FRAMEDIR=$(dirname $0)
 for i in {0..35}
 do
     frame=$(printf "%03d" $i)
-    angle=$(($i * 10))
+    angle=$((i * 10))
     convert $FRAMEDIR/../src/spinner.png -background "rgba(0,0,0,0.0)" -distort SRT $angle $FRAMEDIR/spinner-$frame.png
 done