diff --git a/Flashing/flash_ts100_linux.sh b/Flashing/flash_ts100_linux.sh
index 943ebf2a..7c8aac06 100755
--- a/Flashing/flash_ts100_linux.sh
+++ b/Flashing/flash_ts100_linux.sh
@@ -1,9 +1,9 @@
-#!/bin/bash
+#!/bin/sh
 # TS100 Flasher for Linux by Alex Wigen (https://github.com/awigen)
 
 DIR_TMP="/tmp/ts100"
 
-function usage() {
+usage() {
     echo
     echo "#################"
     echo "# TS100 Flasher #"
@@ -18,36 +18,32 @@ function usage() {
 }
 
 GAUTOMOUNT=0
-function disable_gautomount {
-    GSETTINGS=$(which gsettings)
-    if [ $? -ne 0 ]; then
+disable_gautomount() {
+    if ! GSETTINGS=$(which gsettings); then
         return 1
     fi
-    gsettings get org.gnome.desktop.media-handling automount | grep true > /dev/null
-    if [ $? -eq 0 ]; then
+    if ! gsettings get org.gnome.desktop.media-handling automount | grep true > /dev/null; then
         GAUTOMOUNT=1
         gsettings set org.gnome.desktop.media-handling automount false
     fi
 }
 
-function enable_gautomount {
+enable_gautomount() {
     if [ "$GAUTOMOUNT" -ne 0 ]; then
         gsettings set org.gnome.desktop.media-handling automount true
     fi
 }
 
-function is_attached {
-    output=$(lsblk -b --raw --output NAME,MODEL | grep 'DFU.*Disk')
-    if [ $? -ne 0 ]; then
+is_attached() {
+    if ! output=$(lsblk -b --raw --output NAME,MODEL | grep 'DFU.*Disk'); then
       return 1
     fi
-    DEVICE=$(echo $output | awk '{print "/dev/"$1}')
+    DEVICE=$(echo "$output" | awk '{print "/dev/"$1}')
 }
 
 instructions="not printed"
-function wait_for_ts100 {
-    is_attached
-    while [ $? -ne 0 ]; do
+wait_for_ts100() {
+    while ! is_attached; do
         if [ "$instructions" = "not printed" ]; then
             echo
             echo "#####################################################"
@@ -60,29 +56,27 @@ function wait_for_ts100 {
             instructions="printed"
         fi
         sleep 0.1
-        is_attached
     done
 }
 
-function mount_ts100 {
+mount_ts100() {
     mkdir -p "$DIR_TMP"
-    sudo mount -t msdos -o uid=$UID "$DEVICE" "$DIR_TMP"
-    if [ $? -ne 0 ]; then
+    user="${UID:-$(id -u)}"
+    if ! sudo mount -t msdos -o uid=$user "$DEVICE" "$DIR_TMP"; then
         echo "Failed to mount $DEVICE on $DIR_TMP"
         exit 1
     fi
 }
 
-function umount_ts100 {
-    mountpoint "$DIR_TMP" > /dev/null && sudo umount "$DIR_TMP"
-    if [ $? -ne 0 ]; then
+umount_ts100() {
+    if ! mountpoint "$DIR_TMP" > /dev/null && sudo umount "$DIR_TMP"; then
         echo "Failed to unmount $DIR_TMP"
         exit 1
     fi
     rmdir "$DIR_TMP"
 }
 
-function cleanup {
+cleanup() {
     enable_gautomount
     if [ -d "$DIR_TMP" ]; then
         umount_ts100
@@ -102,7 +96,7 @@ if [ ! -f "$1" ]; then
     exit 1
 fi
 
-if [ $(head -c1 "$1") != ":" ] || [ $(tail -n1 "$1" | head -c1) != ":" ]; then
+if [ "$(head -c1 "$1")" != ":" ] || [ "$(tail -n1 "$1" | head -c1)" != ":" ]; then
     echo "'$1' doesn't look like a valid HEX file. Please provide a HEX file to flash"
     usage
     exit 1
diff --git a/build.sh b/build.sh
index 10f26c0d..268abd28 100644
--- a/build.sh
+++ b/build.sh
@@ -1,2 +1,2 @@
-#!/usr/bin/env bash
-docker-compose run --rm builder /bin/bash /build/ci/buildAll.sh
\ No newline at end of file
+#!/bin/sh
+docker-compose run --rm builder /bin/bash /build/ci/buildAll.sh
diff --git a/ci/buildAll.sh b/ci/buildAll.sh
index f285530a..566cfe72 100755
--- a/ci/buildAll.sh
+++ b/ci/buildAll.sh
@@ -1,4 +1,4 @@
-#!/usr/bin/env bash
+#!/bin/sh
 set -e
 set -u
 
diff --git a/setup.sh b/setup.sh
index 6db08bed..00c460da 100644
--- a/setup.sh
+++ b/setup.sh
@@ -1,7 +1,7 @@
-#!/bin/bash
+#!/bin/sh
 set -e
 # Setup shell file to setup the environment on an ubuntu machine
-sudo apt-get update && sudo apt-get install -y make bzip2 git python3 python3-pip wget  dfu-util
+sudo apt-get update && sudo apt-get install -y make bzip2 git python3 python3-pip wget dfu-util
 python3 -m pip install bdflib black flake8
 sudo mkdir -p /build
 cd /build
@@ -12,7 +12,7 @@ cd /build
 MDPATH=${GITHUB_WORKSPACE:-/build/source/}
 sudo mkdir -p /build/cache
 cd /build/cache/
-if md5sum -c $MDPATH/ci/gcc-arm-none-eabi-10-2020-q4-major-x86_64-linux.tar.bz2.md5; then
+if md5sum -c "$MDPATH"/ci/gcc-arm-none-eabi-10-2020-q4-major-x86_64-linux.tar.bz2.md5; then
     echo "Good MD5 ARM"
 else
     echo "ARM MD5 Mismatch, downloading fresh"
@@ -20,7 +20,7 @@ else
     sudo wget -q "https://developer.arm.com/-/media/Files/downloads/gnu-rm/10-2020q4/gcc-arm-none-eabi-10-2020-q4-major-x86_64-linux.tar.bz2" -O gcc-arm-none-eabi-10-2020-q4-major-x86_64-linux.tar.bz2
 fi
 
-if md5sum -c $MDPATH/ci/nuclei_riscv_newlibc_prebuilt_linux64_2020.08.tar.bz2.md5; then
+if md5sum -c "$MDPATH"/ci/nuclei_riscv_newlibc_prebuilt_linux64_2020.08.tar.bz2.md5; then
     echo "Good MD5 RISCV"
 else
     echo "RISCV MD5 Mismatch, downloading fresh"
diff --git a/source/build.sh b/source/build.sh
index 8d3700fe..643af510 100755
--- a/source/build.sh
+++ b/source/build.sh
@@ -77,7 +77,7 @@ echo "*********************************************"
 
 # Calculate available languages
 for f in "$TRANSLATION_DIR"/translation_*.json; do
-    AVAILABLE_LANGUAGES+=($(echo $f | tr "[:lower:]" "[:upper:]" | sed "s/[^_]*_//" | sed "s/\.JSON//g"))
+    AVAILABLE_LANGUAGES+=("$(echo "$f" | tr "[:lower:]" "[:upper:]" | sed "s/[^_]*_//" | sed "s/\.JSON//g")")
 done
 
 # Checking requested language
@@ -124,8 +124,8 @@ if [ ${#BUILD_LANGUAGES[@]} -gt 0 ] && [ ${#BUILD_MODELS[@]} -gt 0 ]; then
     checkLastCommand
 
     for model in "${BUILD_MODELS[@]}"; do
-        echo "Building firmware for $model in ${BUILD_LANGUAGES[@]}"
-        make -j$(nproc) model="$model" "${BUILD_LANGUAGES[@]/#/firmware-}" >/dev/null
+        echo "Building firmware for $model in ${BUILD_LANGUAGES[*]}"
+        make -j"$(nproc)" model="$model" "${BUILD_LANGUAGES[@]/#/firmware-}" >/dev/null
         checkLastCommand
     done
 else
diff --git a/start_dev.sh b/start_dev.sh
index 8f7bebc9..ef95947f 100755
--- a/start_dev.sh
+++ b/start_dev.sh
@@ -1,2 +1,2 @@
-#!/usr/bin/env bash
-docker-compose run --rm builder
\ No newline at end of file
+#!/bin/sh
+docker-compose run --rm builder