diff --git a/.circleci/config.yml b/.circleci/config.yml
index 834dc97..6f1c2c9 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -34,10 +34,10 @@ jobs:
     <<: *defaults
     docker:
       - image: php:7.3-alpine
-  build-phpRC:
+  build-php74:
     <<: *defaults
     docker:
-      - image: php:rc-alpine
+      - image: php:7.4-alpine
 
 workflows:
   version: 2
@@ -46,4 +46,4 @@ workflows:
       - build-php71
       - build-php72
       - build-php73
-      - build-phpRC
+      - build-php74
diff --git a/composer.json b/composer.json
index 5fe941f..a2a340c 100644
--- a/composer.json
+++ b/composer.json
@@ -9,6 +9,7 @@
     }
   ],
   "require": {
+    "ext-json": "*",
     "php": ">=7.1",
     "psr/log": "1.1.*"
   },
diff --git a/src/BasicGoogleCloudLogger.php b/src/BasicGoogleCloudLogger.php
new file mode 100644
index 0000000..46da42b
--- /dev/null
+++ b/src/BasicGoogleCloudLogger.php
@@ -0,0 +1,39 @@
+<?php
+namespace Packaged\Log;
+
+use Psr\Log\AbstractLogger;
+use Psr\Log\LogLevel;
+
+/**
+ * Logger that outputs the messages using error_log()
+ */
+class BasicGoogleCloudLogger extends ErrorLogLogger
+{
+  private $_handle;
+
+  public function __construct($maxLevel = LogLevel::DEBUG)
+  {
+    parent::__construct($maxLevel);
+    $this->_handle = fopen('php://stderr', 'wb');
+  }
+
+  public function setHandle($handle)
+  {
+    $this->_handle = $handle;
+  }
+
+  protected function _writeLog($message)
+  {
+    fwrite($this->_handle, $message);
+  }
+
+  protected function _formatLog($level, $message, array $context = null)
+  {
+    return json_encode(array_filter([
+        'timestamp'   => (new \DateTime())->format(DATE_RFC3339_EXTENDED),
+        'severity'    => $level,
+        'textPayload' => $message,
+        'jsonPayload' => $context,
+      ])) . PHP_EOL;
+  }
+}
diff --git a/src/ErrorLogLogger.php b/src/ErrorLogLogger.php
index 9dc2dc4..6455c97 100644
--- a/src/ErrorLogLogger.php
+++ b/src/ErrorLogLogger.php
@@ -33,6 +33,11 @@ public function __construct($maxLevel = LogLevel::DEBUG)
     $this->setMaxLogLevel($maxLevel);
   }
 
+  protected function _writeLog($message)
+  {
+    error_log($message);
+  }
+
   /**
    * @param string $level One of the Psr\Log\LogLevel constants
    */
@@ -41,12 +46,21 @@ public function setMaxLogLevel($level)
     $this->_maxLevel = $this->_levelToNum($level);
   }
 
-  public function log($level, $message, array $context = [])
+  public function log($level, $message, array $context = null)
   {
     if($this->_levelToNum($level) <= $this->_maxLevel)
     {
-      error_log($message);
+      $this->_writeLog($this->_formatLog($level, $message, $context));
+    }
+  }
+
+  protected function _formatLog($level, $message, array $context = null)
+  {
+    if(!empty($context))
+    {
+      $message .= ' ' . json_encode($context);
     }
+    return "[$level] $message";
   }
 
   private function _levelToNum($level)
diff --git a/src/Log.php b/src/Log.php
index ff196e1..a59e871 100644
--- a/src/Log.php
+++ b/src/Log.php
@@ -79,11 +79,26 @@ public static function debug($message, array $context = [])
 
   public static function exception(Throwable $e)
   {
-    static::error("EXCEPTION (" . $e->getCode() . "): " . $e->getMessage());
+    static::critical(
+      $e->getMessage(),
+      [
+        'code' => $e->getCode(),
+        'file' => $e->getFile(),
+        'line' => $e->getLine(),
+      ]
+    );
   }
 
   public static function exceptionWithTrace(Throwable $e)
   {
-    static::error("EXCEPTION (" . $e->getCode() . "): " . $e->getMessage() . "\n" . $e->getTraceAsString());
+    static::critical(
+      $e->getMessage(),
+      [
+        'code' => $e->getCode(),
+        'file' => $e->getFile(),
+        'line' => $e->getLine(),
+        'stack_trace' => $e->getTraceAsString(),
+      ]
+    );
   }
 }
diff --git a/tests/AbstractLoggerTestCase.php b/tests/AbstractLoggerTestCase.php
deleted file mode 100644
index 62e8573..0000000
--- a/tests/AbstractLoggerTestCase.php
+++ /dev/null
@@ -1,31 +0,0 @@
-<?php
-
-namespace Packaged\Log\Tests;
-
-use PHPUnit\Framework\TestCase;
-
-abstract class AbstractLoggerTestCase extends TestCase
-{
-  private $_tempFile;
-
-  public function setUp()
-  {
-    $this->_tempFile = tempnam(sys_get_temp_dir(), 'packaged-log-');
-    ini_set('error_log', $this->_tempFile);
-  }
-
-  public function tearDown()
-  {
-    unlink($this->_tempFile);
-  }
-
-  protected function _getLogContents()
-  {
-    return file_get_contents($this->_tempFile);
-  }
-
-  public function assertLastLog($test)
-  {
-    $this->assertStringEndsWith($test . PHP_EOL, $this->_getLogContents());
-  }
-}
diff --git a/tests/BasicGoogleCloudLoggerTest.php b/tests/BasicGoogleCloudLoggerTest.php
new file mode 100644
index 0000000..b54036f
--- /dev/null
+++ b/tests/BasicGoogleCloudLoggerTest.php
@@ -0,0 +1,118 @@
+<?php
+namespace Packaged\Log\Tests;
+
+use Exception;
+use Packaged\Log\BasicGoogleCloudLogger;
+use Packaged\Log\ErrorLogLogger;
+use Packaged\Log\Log;
+use PHPUnit\Framework\TestCase;
+use Psr\Log\LogLevel;
+
+class BasicGoogleCloudLoggerTest extends TestCase
+{
+  private $_tempFile;
+  private $_handler;
+
+  public function setUp()
+  {
+    $this->_tempFile = tempnam(sys_get_temp_dir(), 'packaged-log-');
+    $this->_handler = fopen($this->_tempFile, 'wb');
+  }
+
+  public function tearDown()
+  {
+    fclose($this->_handler);
+    unlink($this->_tempFile);
+  }
+
+  protected function _getLogContents()
+  {
+    return file_get_contents($this->_tempFile);
+  }
+
+  public function assertLastLog($test)
+  {
+    self::assertStringEndsWith($test . PHP_EOL, $this->_getLogContents());
+  }
+
+  private function _getTestLogger($maxLevel = LogLevel::DEBUG)
+  {
+    $l = new BasicGoogleCloudLogger($maxLevel);
+    $l->setHandle($this->_handler);
+    return $l;
+  }
+
+  public function testLogger()
+  {
+    Log::bind($this->_getTestLogger());
+
+    Log::debug('debug: test');
+    self::assertLastLog('","severity":"debug","textPayload":"debug: test"}');
+
+    Log::info('info: test');
+    self::assertLastLog('","severity":"info","textPayload":"info: test"}');
+
+    Log::notice('notice: test');
+    self::assertLastLog('","severity":"notice","textPayload":"notice: test"}');
+
+    Log::warning('warning: test');
+    self::assertLastLog('","severity":"warning","textPayload":"warning: test"}');
+
+    Log::error('error: test');
+    self::assertLastLog('","severity":"error","textPayload":"error: test"}');
+
+    Log::critical('critical: test');
+    self::assertLastLog('","severity":"critical","textPayload":"critical: test"}');
+
+    Log::alert('alert: test');
+    self::assertLastLog('","severity":"alert","textPayload":"alert: test"}');
+
+    Log::emergency('emergency: test');
+    self::assertLastLog('","severity":"emergency","textPayload":"emergency: test"}');
+  }
+
+  public function testLevelLog()
+  {
+    Log::bind($this->_getTestLogger(LogLevel::INFO));
+
+    Log::info('info: test');
+    self::assertLastLog('","severity":"info","textPayload":"info: test"}');
+
+    Log::debug('debug: test');
+    self::assertLastLog('","severity":"info","textPayload":"info: test"}');
+  }
+
+  public function testExceptionLog()
+  {
+    Log::bind($this->_getTestLogger());
+
+    $e = new Exception('exception message', 123);
+    Log::exception($e);
+    self::assertContains(',"textPayload":"exception message"', $this->_getLogContents());
+    self::assertContains(',"severity":"critical"', $this->_getLogContents());
+    self::assertNotContains('"stace_trace":', $this->_getLogContents());
+  }
+
+  public function testExceptionTraceLog()
+  {
+    Log::bind($this->_getTestLogger());
+
+    $e = new Exception('exception message', 123);
+    Log::exceptionWithTrace($e);
+    self::assertContains('"textPayload":"exception message"', $this->_getLogContents());
+    self::assertContains('"severity":"critical"', $this->_getLogContents());
+    self::assertContains('"code":123', $this->_getLogContents());
+    self::assertContains('"line":100', $this->_getLogContents());
+    self::assertContains('BasicGoogleCloudLoggerTest.php', $this->_getLogContents());
+    self::assertContains('"stack_trace"', $this->_getLogContents());
+  }
+
+  public function testContextLog()
+  {
+    Log::bind($this->_getTestLogger());
+    Log::debug('debug: test', ['test1' => 'value1', 'test2' => 'value2']);
+    self::assertLastLog(
+      '","severity":"debug","textPayload":"debug: test","jsonPayload":{"test1":"value1","test2":"value2"}}'
+    );
+  }
+}
diff --git a/tests/ErrorLogLoggerTest.php b/tests/ErrorLogLoggerTest.php
new file mode 100644
index 0000000..b4ed180
--- /dev/null
+++ b/tests/ErrorLogLoggerTest.php
@@ -0,0 +1,117 @@
+<?php
+namespace Packaged\Log\Tests;
+
+use Exception;
+use Packaged\Log\ErrorLogLogger;
+use Packaged\Log\Log;
+use PHPUnit\Framework\TestCase;
+use Psr\Log\LogLevel;
+
+class ErrorLogLoggerTest extends TestCase
+{
+  private $_tempFile;
+
+  public function setUp()
+  {
+    $this->_tempFile = tempnam(sys_get_temp_dir(), 'packaged-log-');
+    ini_set('error_log', $this->_tempFile);
+  }
+
+  public function tearDown()
+  {
+    unlink($this->_tempFile);
+  }
+
+  protected function _getLogContents()
+  {
+    return file_get_contents($this->_tempFile);
+  }
+
+  public function assertLastLog($test)
+  {
+    self::assertStringEndsWith($test . PHP_EOL, $this->_getLogContents());
+  }
+
+  public function testDefaultLogger()
+  {
+    Log::unbind();
+
+    Log::info('info: test');
+    self::assertLastLog('info: test');
+
+    Log::debug('debug: test');
+    self::assertLastLog('debug: test');
+  }
+
+  public function testErrorLogLogger()
+  {
+    Log::bind(new ErrorLogLogger());
+
+    Log::debug('debug: test');
+    self::assertLastLog('debug: test');
+
+    Log::info('info: test');
+    self::assertLastLog('info: test');
+
+    Log::notice('notice: test');
+    self::assertLastLog('notice: test');
+
+    Log::warning('warning: test');
+    self::assertLastLog('warning: test');
+
+    Log::error('error: test');
+    self::assertLastLog('error: test');
+
+    Log::critical('critical: test');
+    self::assertLastLog('critical: test');
+
+    Log::alert('alert: test');
+    self::assertLastLog('alert: test');
+
+    Log::emergency('emergency: test');
+    self::assertLastLog('emergency: test');
+  }
+
+  public function testLevelLog()
+  {
+    Log::bind(new ErrorLogLogger(LogLevel::INFO));
+
+    Log::info('info: test');
+    self::assertLastLog('info: test');
+
+    Log::debug('debug: test');
+    self::assertLastLog('info: test');
+  }
+
+  public function testExceptionLog()
+  {
+    Log::bind(new ErrorLogLogger());
+
+    $e = new Exception('exception message', 123);
+    Log::exception($e);
+    self::assertContains('[critical] exception message ', $this->_getLogContents());
+    self::assertContains('"code":123', $this->_getLogContents());
+    self::assertContains('"line":90', $this->_getLogContents());
+    self::assertContains('ErrorLogLoggerTest.php', $this->_getLogContents());
+  }
+
+  public function testExceptionTraceLog()
+  {
+    Log::bind(new ErrorLogLogger());
+
+    $e = new Exception('exception message', 123);
+    Log::exceptionWithTrace($e);
+    self::assertContains('[critical] exception message ', $this->_getLogContents());
+    self::assertContains('"code":123', $this->_getLogContents());
+    self::assertContains('"line":102', $this->_getLogContents());
+    self::assertContains('ErrorLogLoggerTest.php', $this->_getLogContents());
+    self::assertContains('"stack_trace"', $this->_getLogContents());
+  }
+
+  public function testContextLog()
+  {
+    Log::bind(new ErrorLogLogger());
+    Log::debug('debug: test', ['test1' => 'value1', 'test2' => 'value2']);
+    self::assertLastLog('debug: test {"test1":"value1","test2":"value2"}');
+  }
+}
diff --git a/tests/LoggerTest.php b/tests/LoggerTest.php
deleted file mode 100644
index 56da8cb..0000000
--- a/tests/LoggerTest.php
+++ /dev/null
@@ -1,82 +0,0 @@
-<?php
-namespace Packaged\Log\Tests;
-
-use Exception;
-use Packaged\Log\ErrorLogLogger;
-use Packaged\Log\Log;
-use Psr\Log\LogLevel;
-
-class LoggerTest extends AbstractLoggerTestCase
-{
-  public function testDefaultLogger()
-  {
-    Log::unbind();
-
-    Log::info('info: test');
-    $this->assertLastLog('info: test');
-
-    Log::debug('debug: test');
-    $this->assertLastLog('debug: test');
-  }
-
-  public function testErrorLogLogger()
-  {
-    Log::bind(new ErrorLogLogger());
-
-    Log::debug('debug: test');
-    $this->assertLastLog('debug: test');
-
-    Log::info('info: test');
-    $this->assertLastLog('info: test');
-
-    Log::notice('notice: test');
-    $this->assertLastLog('notice: test');
-
-    Log::warning('warning: test');
-    $this->assertLastLog('warning: test');
-
-    Log::error('error: test');
-    $this->assertLastLog('error: test');
-
-    Log::critical('critical: test');
-    $this->assertLastLog('critical: test');
-
-    Log::alert('alert: test');
-    $this->assertLastLog('alert: test');
-
-    Log::emergency('emergency: test');
-    $this->assertLastLog('emergency: test');
-  }
-
-  public function testLevelLog()
-  {
-    Log::bind(new ErrorLogLogger(LogLevel::INFO));
-
-    Log::info('info: test');
-    $this->assertLastLog('info: test');
-
-    Log::debug('debug: test');
-    $this->assertLastLog('info: test');
-  }
-
-  public function testExceptionLog()
-  {
-    Log::bind(new ErrorLogLogger());
-
-    $e = new Exception('exception message', 123);
-    Log::exception($e);
-    $this->assertLastLog('EXCEPTION (123): exception message');
-  }
-
-  public function testExceptionTraceLog()
-  {
-    Log::bind(new ErrorLogLogger());
-
-    $e = new Exception('exception message', 123);
-    Log::exceptionWithTrace($e);
-    $this->assertContains('EXCEPTION (123): exception message', $this->_getLogContents());
-    $this->assertContains('Packaged\Log\Tests\LoggerTest->testExceptionTraceLog()', $this->_getLogContents());
-    $this->assertContains('#0', $this->_getLogContents());
-    $this->assertContains('{main}', $this->_getLogContents());
-  }
-}