diff --git a/src/__phutil_library_map__.php b/src/__phutil_library_map__.php
--- a/src/__phutil_library_map__.php
+++ b/src/__phutil_library_map__.php
@@ -83,6 +83,8 @@
     'ArcanistGitHookPreReceiveWorkflow' => 'workflow/ArcanistGitHookPreReceiveWorkflow.php',
     'ArcanistGoLintLinter' => 'lint/linter/ArcanistGoLintLinter.php',
     'ArcanistGoLintLinterTestCase' => 'lint/linter/__tests__/ArcanistGoLintLinterTestCase.php',
+    'ArcanistHackLinter' => 'lint/linter/ArcanistHackLinter.php',
+    'ArcanistHackLinterTestCase' => 'lint/linter/__tests__/ArcanistHackLinterTestCase.php',
     'ArcanistHelpWorkflow' => 'workflow/ArcanistHelpWorkflow.php',
     'ArcanistHgClientChannel' => 'hgdaemon/ArcanistHgClientChannel.php',
     'ArcanistHgProxyClient' => 'hgdaemon/ArcanistHgProxyClient.php',
@@ -273,6 +275,8 @@
     'ArcanistGitHookPreReceiveWorkflow' => 'ArcanistWorkflow',
     'ArcanistGoLintLinter' => 'ArcanistExternalLinter',
     'ArcanistGoLintLinterTestCase' => 'ArcanistArcanistLinterTestCase',
+    'ArcanistHackLinter' => 'ArcanistExternalLinter',
+    'ArcanistHackLinterTestCase' => 'ArcanistArcanistLinterTestCase',
     'ArcanistHelpWorkflow' => 'ArcanistWorkflow',
     'ArcanistHgClientChannel' => 'PhutilProtocolChannel',
     'ArcanistHgServerChannel' => 'PhutilProtocolChannel',
diff --git a/src/lint/linter/ArcanistHackLinter.php b/src/lint/linter/ArcanistHackLinter.php
new file mode 100644
--- /dev/null
+++ b/src/lint/linter/ArcanistHackLinter.php
@@ -0,0 +1,144 @@
+<?php
+
+/**
+ * Calls `hh_client` and parses messages issued by the hack type checker
+ */
+final class ArcanistHackLinter extends ArcanistExternalLinter {
+
+  private $hackRootDir = null;
+
+  public function getInfoName() {
+    return 'Hack for HipHop type checker';
+  }
+
+  public function getInfoURI() {
+    return 'http://hacklang.org/';
+  }
+
+  public function getInfoDescription() {
+    return pht('Hack type errors');
+  }
+
+  public function getLinterName() {
+    return 'HACK';
+  }
+
+  public function getLinterConfigurationName() {
+    return 'hh_client';
+  }
+
+  public function getDefaultBinary() {
+    return 'hh_client';
+  }
+
+  public function getVersion() {
+    list($err, $stdout, $stderr) = exec_manual(
+      '%C --json check %s',
+      $this->getExecutableCommand(),
+      $this->getEngine()->getWorkingCopy()->getProjectRoot());
+
+    if ($err === 1) {
+      return false;
+    }
+
+    $output = last(explode("\n", trim($stderr)));
+    return idx(phutil_json_decode($output), 'version', false);
+  }
+
+  public function getInstallInstructions() {
+    return pht('Follow the instructions at http://hacklang.org/install/');
+  }
+
+  public function shouldExpectCommandErrors() {
+    return true;
+  }
+
+  public function supportsReadDataFromStdin() {
+    return false;
+  }
+
+  protected function getMandatoryFlags() {
+    $arguments = array('--json', 'check');
+    $arguments[] = $this->getEngine()->getWorkingCopy()->getProjectRoot();
+    return $arguments;
+  }
+
+  protected function getPathArgumentForLinterFuture($path) {
+    return '';
+  }
+
+  protected function parseLinterOutput($path, $err, $stdout, $stderr) {
+    // `hh_client` uses 0 for success, 1 for failure, 2 for type errors
+    if ($err === 1) {
+      return false;
+    }
+
+    $json = last(explode("\n", trim($stderr)));
+    $results = phutil_json_decode($json);
+    $passed = idx($results, 'passed', false);
+    $errors = idx($results, 'errors', array());
+
+    if ($passed) {
+      // everything typechecks!
+      return array();
+    }
+
+    $paths = array();
+    foreach ($this->paths as $current_path) {
+      $paths[$this->getEngine()->getFilePathOnDisk($path)] = true;
+    }
+
+    $lint_messages = array();
+    foreach ($errors as $current_error) {
+      // Each Hack error consists of a list of messages; each message
+      // has its own position info. We report the error at the first
+      // location that matches a path affect by the current diff.
+      //
+      // Location keys are:
+      // - descr : string
+      // - path : string
+      // - line : int
+      // - start : int
+      // - end : int
+
+      $message = $current_error['message'];
+      foreach ($message as $location) {
+        $location_path = $location['path'];
+        if (array_key_exists($location_path, $paths)) {
+          $warning = array(
+              'path' => $current_path,
+              'line' => $location['line'],
+              'char' => $location['start'],
+              'name' => 'Hack type error',
+              'code' => $this->getLinterName(),
+              'description' => $this->formatDescription($message),
+              'severity' => ArcanistLintSeverity::SEVERITY_ERROR
+          );
+
+          $lint_messages[] = ArcanistLintMessage::newFromDictionary($warning);
+          break;
+        }
+      }
+    }
+
+    return $lint_messages;
+  }
+
+  private function formatDescription($error) {
+    $result = array();
+    $result[] = 'Type error(s):';
+    foreach ($error as $location) {
+      $description = sprintf(
+          "File %s line %d:%d-%d\n%s",
+          $location['path'],
+          $location['line'],
+          $location['start'],
+          $location['end'],
+          $location['descr']);
+
+      $result[] = $description;
+    }
+
+    return implode("\n", $result);
+  }
+}
diff --git a/src/lint/linter/__tests__/ArcanistHackLinterTestCase.php b/src/lint/linter/__tests__/ArcanistHackLinterTestCase.php
new file mode 100644
--- /dev/null
+++ b/src/lint/linter/__tests__/ArcanistHackLinterTestCase.php
@@ -0,0 +1,20 @@
+<?php
+
+final class ArcanistHackLinterTestCase extends ArcanistArcanistLinterTestCase {
+
+  public function testJSONLintLinter() {
+    $testdir = dirname(__FILE__).'/hack/';
+    $this->executeTestsInDirectory(
+      $testdir,
+      new ArcanistHackLinter());
+  }
+
+  protected function fixupTempDir($path) {
+    $hhconfig = Filesystem::resolvePath('.hhconfig', $path);
+    Filesystem::writeFile($hhconfig, "\n");
+  }
+
+  protected function getFilenameSuffix() {
+    return '.php';
+  }
+}
diff --git a/src/lint/linter/__tests__/ArcanistLinterTestCase.php b/src/lint/linter/__tests__/ArcanistLinterTestCase.php
--- a/src/lint/linter/__tests__/ArcanistLinterTestCase.php
+++ b/src/lint/linter/__tests__/ArcanistLinterTestCase.php
@@ -22,6 +22,14 @@
       pht('Expected to find some .lint-test tests in directory %s!', $root));
   }
 
+  protected function fixupTempDir($path) {
+    return;
+  }
+
+  protected function getFilenameSuffix() {
+    return '';
+  }
+
   private function lintFile($file, ArcanistLinter $linter) {
     $linter = clone $linter;
 
@@ -59,11 +67,12 @@
     $caught_exception = false;
 
     try {
-      $tmp = new TempFile($basename);
+      $tmp = new TempFile($basename.$this->getFilenameSuffix());
       Filesystem::writeFile($tmp, $data);
       $full_path = (string)$tmp;
 
       $dir = dirname($full_path);
+      $this->fixupTempDir($dir);
       $path = basename($full_path);
       $config_file = null;
       $arcconfig = idx($config, 'arcconfig');
diff --git a/src/lint/linter/__tests__/hack/01_basic_error.lint-test b/src/lint/linter/__tests__/hack/01_basic_error.lint-test
new file mode 100644
--- /dev/null
+++ b/src/lint/linter/__tests__/hack/01_basic_error.lint-test
@@ -0,0 +1,11 @@
+<?hh // strict
+
+class Test {
+
+  public function foo(string $x): int {
+    return "five";
+  }
+
+}
+~~~~~~~~~~
+error:6:12
\ No newline at end of file
diff --git a/src/lint/linter/__tests__/hack/02_no_hack_error.lint-test b/src/lint/linter/__tests__/hack/02_no_hack_error.lint-test
new file mode 100644
--- /dev/null
+++ b/src/lint/linter/__tests__/hack/02_no_hack_error.lint-test
@@ -0,0 +1,10 @@
+<?hh // strict
+
+class Test {
+
+  public function foo(string $x): int {
+    return 5;
+  }
+
+}
+~~~~~~~~~~