diff --git a/tasks/connection_check.php b/tasks/connection_check.php
index 623b73d..2739052 100644
--- a/tasks/connection_check.php
+++ b/tasks/connection_check.php
@@ -62,7 +62,8 @@
 $command = 'ssh -q '.$ssh_username.'@'.$ssh_hostname.' "bash -c \"test -f '.$remote_wp_cli.' && echo true || echo false\""';
 $live_server_check = exec($command);
 
-if ($live_server_check == 'false') {
+// Anything but an explicit 'true' (e.g. no output from a dropped connection) is a failure
+if ($live_server_check !== 'true') {
 
   // Exit Messages
   task_message('Connected but cannot find remote WP-CLI', 'Error', 31, false);
diff --git a/tasks/database_sync.php b/tasks/database_sync.php
index 54bf900..473085e 100644
--- a/tasks/database_sync.php
+++ b/tasks/database_sync.php
@@ -7,7 +7,7 @@
 task_message($task_name);
 
 // pv check
-if (`which pv`) {
+if (shell_exec('which pv')) {
   $pipe = '| pv |';
 } else {
   task_message('Install the \'pv\' command to monitor import progress', 'Notice', 33, false);
@@ -16,12 +16,18 @@
 
 $command = 'ssh '.$ssh_username.'@'.$ssh_hostname.' "bash -c \"cd '.$rem_proj_loc.' && '.$remote_wp_cli.' db export --single-transaction -\"" '.$pipe.' '.$local_wp_cli.' db import -';
 debug_message($command);
-system($command);
+// pipefail catches a failed export, not just a failed import
+system('bash -c '.escapeshellarg('set -o pipefail; '.$command), $db_status);
+
+if ($db_status !== 0) {
+  task_message('Database sync failed (exit code '.$db_status.')', 'Error', 31);
+  $fail_count++;
+}
 
 /**
- * TASK: Post sync queries
+ * TASK: Post sync queries (skipped if the import failed)
  */
-if ($queries = $_ENV['DEV_POST_SYNC_QUERIES']) {
+if ($db_status === 0 && ($queries = $_ENV['DEV_POST_SYNC_QUERIES'])) {
   $command = $local_wp_cli . ' db query "' . preg_replace('/(`|")/i', '\\\\${1}', $queries) . '"';
   debug_message($command);
   system($command);
diff --git a/tasks/plugins_sync.php b/tasks/plugins_sync.php
index 3833faa..71dd60d 100644
--- a/tasks/plugins_sync.php
+++ b/tasks/plugins_sync.php
@@ -13,11 +13,16 @@
   return;
 }
 
-if (`which rsync`) {
+if (shell_exec('which rsync')) {
   task_message($task_name);
-  $command = 'rsync -avhP ' . $ssh_username . '@' . $ssh_hostname . ':' . $rem_proj_loc . '/' . $plugin_dir . '/ ./' . $plugin_dir . '/';
+  $command = 'rsync -avhP ' . escapeshellarg($ssh_username . '@' . $ssh_hostname . ':' . $rem_proj_loc . '/' . $plugin_dir . '/') . ' ' . escapeshellarg('./' . $plugin_dir . '/');
   debug_message($command);
-  system($command);
+  system($command, $rsync_status);
+
+  if ($rsync_status !== 0 && $rsync_status !== 24) {
+    task_message($task_name.' failed (rsync exit code '.$rsync_status.')', 'Error', 31);
+    $fail_count++;
+  }
 } else {
   task_message($task_name.' task not ran, please install \'rsync\'', 'Error', 31);
   $fail_count++;
diff --git a/tasks/uploads_sync.php b/tasks/uploads_sync.php
index 965197b..b1936fc 100644
--- a/tasks/uploads_sync.php
+++ b/tasks/uploads_sync.php
@@ -9,15 +9,21 @@
 if ($exclude_dirs = $_ENV['DEV_SYNC_DIR_EXCLUDES']) {
   $exclude_dirs = explode(',', $exclude_dirs);
   foreach ($exclude_dirs as $dir) {
-    $excludes .= ' --exclude=' . $dir;
+    $excludes .= ' --exclude=' . escapeshellarg($dir);
   }
 }
 
-if (`which rsync`) {
+if (shell_exec('which rsync')) {
   task_message($task_name);
-  $command = 'rsync -avhP ' . $ssh_username . '@' . $ssh_hostname . ':' . $rem_proj_loc . '/' . $upload_dir . '/ ./' . $upload_dir . '/' . $excludes;
+  $command = 'rsync -avhP ' . escapeshellarg($ssh_username . '@' . $ssh_hostname . ':' . $rem_proj_loc . '/' . $upload_dir . '/') . ' ' . escapeshellarg('./' . $upload_dir . '/') . $excludes;
   debug_message($command);
-  system($command);
+  system($command, $rsync_status);
+
+  // 24 = files vanished mid-transfer, routine on a live uploads folder
+  if ($rsync_status !== 0 && $rsync_status !== 24) {
+    task_message($task_name.' failed (rsync exit code '.$rsync_status.')', 'Error', 31);
+    $fail_count++;
+  }
 } else {
   task_message($task_name.' task not ran, please install \'rsync\'', 'Error', 31);
   $fail_count++;