diff --git a/src/lint/linter/ArcanistExternalLinter.php b/src/lint/linter/ArcanistExternalLinter.php
--- a/src/lint/linter/ArcanistExternalLinter.php
+++ b/src/lint/linter/ArcanistExternalLinter.php
@@ -277,9 +277,9 @@
     $binary = $this->getBinary();
 
     if ($interpreter) {
-      $bin = csprintf('%s %s', $interpreter, $binary);
+      $bin = csprintf('%C %s', $interpreter, $binary);
     } else {
-      $bin = csprintf('%s', $binary);
+      $bin = csprintf('%C', $binary);
     }
 
     return $bin;
diff --git a/src/lint/linter/ArcanistPuppetLintLinter.php b/src/lint/linter/ArcanistPuppetLintLinter.php
--- a/src/lint/linter/ArcanistPuppetLintLinter.php
+++ b/src/lint/linter/ArcanistPuppetLintLinter.php
@@ -38,7 +38,7 @@
     list($stdout) = execx('%C --version', $this->getExecutableCommand());
 
     $matches = array();
-    $regex = '/^puppet-lint (?P<version>\d+\.\d+\.\d+)$/';
+    $regex = '/^puppet-lint (?P<version>\d+\.\d+\.\d+)\s*$/';
     if (preg_match($regex, $stdout, $matches)) {
       return $matches['version'];
     } else {
diff --git a/src/lint/linter/ArcanistRuboCopLinter.php b/src/lint/linter/ArcanistRuboCopLinter.php
--- a/src/lint/linter/ArcanistRuboCopLinter.php
+++ b/src/lint/linter/ArcanistRuboCopLinter.php
@@ -34,7 +34,7 @@
     list($stdout) = execx('%C --version', $this->getExecutableCommand());
 
     $matches = array();
-    if (preg_match('/^(?P<version>\d+\.\d+\.\d+)$/', $stdout, $matches)) {
+    if (preg_match('/^(?P<version>\d+\.\d+\.\d+)\s*$/', $stdout, $matches)) {
       return $matches['version'];
     } else {
       return false;