diff --git a/scripts/check_style.sh b/scripts/check_style.sh
index 0ad19a635..f0fae1eb6 100755
--- a/scripts/check_style.sh
+++ b/scripts/check_style.sh
@@ -14,7 +14,7 @@ EXCLUDE_FILES_JOINED=${EXCLUDE_FILES_JOINED%??}
 
 (
 REPO_ROOT="$(dirname "$0")"/..
-cd $REPO_ROOT
+cd "$REPO_ROOT"
 
 WHITESPACE=$(git grep -n -I -E "^.*[[:space:]]+$" |
   grep -v "test/libsolidity/ASTJSON\|test/libsolidity/ASTRecoveryTests\|test/compilationTests/zeppelin/LICENSE\|${EXCLUDE_FILES_JOINED}"
@@ -22,8 +22,8 @@ WHITESPACE=$(git grep -n -I -E "^.*[[:space:]]+$" |
 
 if [[ "$WHITESPACE" != "" ]]
 then
-	echo "Error: Trailing whitespace found:" | tee -a $ERROR_LOG
-	echo "$WHITESPACE" | tee -a $ERROR_LOG
+	echo "Error: Trailing whitespace found:" | tee -a "$ERROR_LOG"
+	echo "$WHITESPACE" | tee -a "$ERROR_LOG"
 	scripts/report_errors.sh "$ERROR_LOG"
 	exit 1
 fi
@@ -51,8 +51,8 @@ FORMATERROR=$(
 
 if [[ "$FORMATERROR" != "" ]]
 then
-	echo "Coding style error:" | tee -a $ERROR_LOG
-	echo "$FORMATERROR" | tee -a $ERROR_LOG
+	echo "Coding style error:" | tee -a "$ERROR_LOG"
+	echo "$FORMATERROR" | tee -a "$ERROR_LOG"
 	scripts/report_errors.sh "$ERROR_LOG"
 	exit 1
 fi
diff --git a/scripts/report_errors.sh b/scripts/report_errors.sh
index c4e370758..dc5c73df8 100755
--- a/scripts/report_errors.sh
+++ b/scripts/report_errors.sh
@@ -4,16 +4,16 @@ ERROR_LOG="$1"
 
 function report_error_to_github
 {
-    if [ -z $CIRCLE_PR_NUMBER ]
+    if [ -z "$CIRCLE_PR_NUMBER" ]
     then
         CIRCLE_PR_NUMBER="${CIRCLE_PULL_REQUEST//[^0-9]/}"
     fi
 
-    ERROR_MSG=$(cat $ERROR_LOG)
+    ERROR_MSG=$(cat "$ERROR_LOG")
 
-    echo $ERROR_MSG
+    echo "$ERROR_MSG"
 
-    if [ ! -z $CI ]
+    if [ ! -z "$CI" ]
     then
         echo "posting error message to github"
         post_error_to_github
@@ -25,15 +25,15 @@ function post_error_to_github
 {
     GITHUB_API_URL="https://api.github.com/repos/$CIRCLE_PROJECT_USERNAME/$CIRCLE_PROJECT_REPONAME/issues/$CIRCLE_PR_NUMBER/comments"
 
-    ESCAPED_ERROR_MSG=$(cat -e $ERROR_LOG | sed 's/\\/\\\\/g' | sed 's/"/\\\"/g')
+    ESCAPED_ERROR_MSG=$(cat -e "$ERROR_LOG" | sed 's/\\/\\\\/g' | sed 's/"/\\\"/g')
 
-    FORMATTED_ERROR_MSG=$(echo $ESCAPED_ERROR_MSG | sed 's/\$/\\n/g' | tr -d '\n')
+    FORMATTED_ERROR_MSG=$(echo "$ESCAPED_ERROR_MSG" | sed 's/\$/\\n/g' | tr -d '\n')
 
     curl --request POST \
-        --url $GITHUB_API_URL \
+        --url "$GITHUB_API_URL" \
         --header 'accept: application/vnd.github.v3+json' \
         --header 'content-type: application/json' \
-        -u stackenbotten:$GITHUB_ACCESS_TOKEN \
+        -u "stackenbotten:$GITHUB_ACCESS_TOKEN" \
         --data "{\"body\": \"There was an error when running \`$CIRCLE_JOB\` for commit \`$CIRCLE_SHA1\`:\n\`\`\`\n$FORMATTED_ERROR_MSG\n\`\`\`\nPlease check that your changes are working as intended.\"}"
 }
 
@@ -41,22 +41,22 @@ function post_review_comment_to_github
 {
     GITHUB_API_URL="https://api.github.com/repos/$CIRCLE_PROJECT_USERNAME/$CIRCLE_PROJECT_REPONAME/pulls/$CIRCLE_PR_NUMBER/comments"
 
-    sed -i 1d $ERROR_LOG
+    sed -i 1d "$ERROR_LOG"
 
     while read line
     do
-        ERROR_PATH=$(echo $line | grep -oE ".*\.cpp")
-        ERROR_LINE=$(echo $line | grep -oE "[0-9]*")
+        ERROR_PATH=$(echo "$line" | grep -oE ".*\.cpp")
+        ERROR_LINE=$(echo "$line" | grep -oE "[0-9]*")
         [[ $ERROR_PATH != "" ]] || { echo "ERROR: Error message does not contain file path."; exit 1; }
         [[ $ERROR_LINE != "" ]] || { echo "ERROR: Error message does not contain line number."; exit 1; }
 
         curl --request POST \
-            --url $GITHUB_API_URL \
+            --url "$GITHUB_API_URL" \
             --header 'accept: application/vnd.github.v3+json, application/vnd.github.comfort-fade-preview+json' \
             --header 'content-type: application/json' \
-            -u stackenbotten:$GITHUB_ACCESS_TOKEN \
+            -u "stackenbotten:$GITHUB_ACCESS_TOKEN" \
             --data "{\"commit_id\": \"$CIRCLE_SHA1\", \"path\": \"$ERROR_PATH\", \"line\": $ERROR_LINE, \"side\": \"RIGHT\", \"body\": \"Coding style error\"}"
-    done < $ERROR_LOG
+    done < "$ERROR_LOG"
 }
 
 report_error_to_github