Kanboard requires at least PHP 5.6 now

vendor/symfony/console/Tests/Fixtures/FooLockCommand.php

@@ -0,0 +1,27 @@
+<?php
+
+use Symfony\Component\Console\Command\Command;
+use Symfony\Component\Console\Command\LockableTrait;
+use Symfony\Component\Console\Input\InputInterface;
+use Symfony\Component\Console\Output\OutputInterface;
+
+class FooLockCommand extends Command
+{
+    use LockableTrait;
+
+    protected function configure()
+    {
+        $this->setName('foo:lock');
+    }
+
+    protected function execute(InputInterface $input, OutputInterface $output)
+    {
+        if (!$this->lock()) {
+            return 1;
+        }
+
+        $this->release();
+
+        return 2;
+    }
+}