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
@@ -335,6 +335,7 @@
     'PhutilUtilsTestCase' => 'utils/__tests__/PhutilUtilsTestCase.php',
     'PhutilWordPressAuthAdapter' => 'auth/PhutilWordPressAuthAdapter.php',
     'PhutilWordPressFuture' => 'future/wordpress/PhutilWordPressFuture.php',
+    'PhutilXHPASTBinary' => 'parser/xhpast/bin/PhutilXHPASTBinary.php',
     'PhutilXHPASTSyntaxHighlighter' => 'markup/syntax/highlighter/PhutilXHPASTSyntaxHighlighter.php',
     'PhutilXHPASTSyntaxHighlighterFuture' => 'markup/syntax/highlighter/xhpast/PhutilXHPASTSyntaxHighlighterFuture.php',
     'PhutilXHPASTSyntaxHighlighterTestCase' => 'markup/syntax/highlighter/__tests__/PhutilXHPASTSyntaxHighlighterTestCase.php',
diff --git a/src/parser/xhpast/bin/PhutilXHPASTBinary.php b/src/parser/xhpast/bin/PhutilXHPASTBinary.php
new file mode 100644
--- /dev/null
+++ b/src/parser/xhpast/bin/PhutilXHPASTBinary.php
@@ -0,0 +1,123 @@
+<?php
+
+final class PhutilXHPASTBinary {
+
+  /**
+   * The current XHPAST version.
+   *
+   * This is the version that would be obtained with an up-to-date XHPAST
+   * build. The //actual// XHPAST build version may vary.
+   */
+  const VERSION = 'xhpast version 5.5.8/1g';
+
+  /**
+   * The XHPAST build version.
+   *
+   * Cache the result from @{method:getVersion} to prevent excessive calls to
+   * @{function:execx}.
+   */
+  private static $version;
+
+  /**
+   * Builds XHPAST automatically.
+   *
+   * Attempts to build the XHPAST binary automatically. Throws a
+   * @{class:CommandException} in the event of a failure.
+   *
+   * @return void
+   */
+  public static function build() {
+    execx('%s', self::getBuildPath());
+    self::$version = null;
+  }
+
+  /**
+   * Returns human-readable instructions for building XHPAST.
+   *
+   * @return string
+   */
+  public static function getBuildInstructions() {
+    return phutil_console_format(
+      "%s:\n\n  \$ %s\n",
+      pht(
+        "Your version of '%s' is unbuilt or out of date. Run this ".
+        "script to build it",
+        'xhpast'),
+      self::getBuildPath());
+  }
+
+  /**
+   * Returns the path to the script used to build XHPAST.
+   *
+   * @return string
+   */
+  private function getBuildPath() {
+    $root = phutil_get_library_root('phutil');
+    $make = $root.'/../scripts/build_xhpast.sh';
+    return Filesystem::resolvePath($make);
+  }
+
+  /**
+   * Constructs an @{class:ExecFuture} for XHPAST.
+   *
+   * @param  wild        Data to pass to the future.
+   * @return ExecFuture
+   */
+  public static function getParserFuture($data) {
+    if (!self::isAvailable()) {
+      try {
+        // Try to build XHPAST automatically. If we can't then just ask the
+        // user to build it themselves.
+        self::build();
+      } catch (CommandException $ex) {
+        throw new PhutilProxyException(self::getBuildInstructions(), $ex);
+      }
+    }
+    $future = new ExecFuture('%s', self::getPath());
+    $future->write($data);
+
+    return $future;
+  }
+
+  /**
+   * Returns the path to the XHPAST binary.
+   *
+   * @return string
+   */
+  public static function getPath() {
+    if (phutil_is_windows()) {
+      return dirname(__FILE__).'\\xhpast.exe';
+    }
+    return dirname(__FILE__).'/xhpast';
+  }
+
+  /**
+   * Returns the XHPAST version.
+   *
+   * @return string
+   */
+  public static function getVersion() {
+    if (self::$version === null) {
+      $bin = self::getPath();
+
+      if (Filesystem::pathExists($bin)) {
+        list($err, $stdout) = exec_manual('%s --version', $bin);
+        if (!$err) {
+          self::$version = trim($stdout);
+        }
+      }
+    }
+
+    return self::$version;
+  }
+
+  /**
+   * Checks if XHPAST is built and up-to-date.
+   *
+   * @return bool
+   */
+  public static function isAvailable() {
+    return self::getVersion() == self::VERSION;
+  }
+
+}
diff --git a/src/parser/xhpast/bin/xhpast_parse.php b/src/parser/xhpast/bin/xhpast_parse.php
--- a/src/parser/xhpast/bin/xhpast_parse.php
+++ b/src/parser/xhpast/bin/xhpast_parse.php
@@ -1,101 +1,25 @@
 <?php
 
-/**
- * Builds XHPAST automatically.
- *
- * Attempts to build the XHPAST binary automatically. Throws a
- * @{class:CommandException} in the event of a failure.
- *
- * @return void
- */
 function xhpast_build() {
-  $root = phutil_get_library_root('phutil');
-  execx('%s', $root.'/../scripts/build_xhpast.sh');
+  return PhutilXHPASTBinary::build();
 }
 
-/**
- * Returns the path to the XHPAST binary.
- *
- * @return string
- */
 function xhpast_get_binary_path() {
-  if (phutil_is_windows()) {
-    return dirname(__FILE__).'\\xhpast.exe';
-  }
-  return dirname(__FILE__).'/xhpast';
+  return PhutilXHPASTBinary::getPath();
 }
 
-/**
- * Returns human-readable instructions for building XHPAST.
- *
- * @return string
- */
 function xhpast_get_build_instructions() {
-  $root = phutil_get_library_root('phutil');
-  $make = $root.'/../scripts/build_xhpast.sh';
-  $make = Filesystem::resolvePath($make);
-  return <<<EOHELP
-Your version of 'xhpast' is unbuilt or out of date. Run this script to build it:
-
-  \$ {$make}
-
-EOHELP;
+  return PhutilXHPASTBinary::getBuildInstructions();
 }
 
-/**
- * Constructs an @{class:ExecFuture} for XHPAST.
- *
- * @param  wild        Data to pass to the future.
- * @return ExecFuture
- */
 function xhpast_get_parser_future($data) {
-  if (!xhpast_is_available()) {
-    try {
-      // Try to build XHPAST automatically. If we can't then just ask the user
-      // to build it themselves.
-      xhpast_build();
-    } catch (CommandException $ex) {
-      throw new PhutilProxyException(xhpast_get_build_instructions(), $ex);
-    }
-  }
-  $future = new ExecFuture('%s', xhpast_get_binary_path());
-  $future->write($data);
-
-  return $future;
+  return PhutilXHPASTBinary::getParserFuture($data);
 }
 
-/**
- * Checks if XHPAST is built and up-to-date.
- *
- * @return bool
- */
 function xhpast_is_available() {
-  static $available;
-
-  if ($available === null) {
-    $available = xhpast_version() == 'xhpast version 5.5.8/1g';
-  }
-
-  return $available;
+  return PhutilXHPASTBinary::isAvailable();
 }
 
-/**
- * Returns the XHPAST version.
- *
- * @return string
- */
 function xhpast_version() {
-  static $version;
-
-  if ($version === null) {
-    $bin = xhpast_get_binary_path();
-    if (Filesystem::pathExists($bin)) {
-      list($err, $stdout) = exec_manual('%s --version', $bin);
-      if (!$err) {
-        $version = trim($stdout);
-      }
-    }
-  }
-
-  return $version;
+  return PhutilXHPASTBinary::getVersion();
 }