In order to set project specific configuration options, simply add a php.ini file to your project, and then run the built-in server with this flag:php -S localhost:8000 -c php.iniThis is especially helpful for settings that cannot be set at runtime (ini_set()).

It’s not mentioned directly, and may not be obvious, but you can also use this to create a virtual host. This, of course, requires the help of your hosts file.Here are the steps:1    /etc/hosts    127.0.0.1    www.example.com2    cd [root folder]    php -S www.example.com:80003    Browser:    http://www.example.com:8000/index.phpCombined with a simple SQLite database, you have a very handy testing environment.

I painfully experienced behaviour that I can't seem to find documented here so I wanted to save everyone from repeating my mistake by giving the following heads up:When starting php -S on a mac (in my case macOS Sierra) to host a local server, I had trouble with connecting from legacy Java. As it turned out, if you started the php server with "php -S localhost:80" the server will be started with ipv6 support only!To access it via ipv4, you need to change the start up command like so: "php -S 127.0.0.1:80"which starts server in ipv4 mode only.

If your URI contains a dot, you'll lose the $_SERVER['PATH_INFO'] variable, when using the built-in webserver.I wanted to write an API, and use .json ending in the URI-s, but then the framework's routing mechanism broke, and it took a lot of time to discover that the reason behind it was its router relying on $_SERVER['PATH_INFO'].References:https://bugs.php.net/bug.php?id=61286

To output debugging information on the command line you can write output to php://stdout:<?php$path = $_SERVER["SCRIPT_FILENAME"];file_put_contents("php://stdout", "\nRequested: $path");echo "<p>Hello World</p>";?>

On Windows you may find useful to have a phpserver.bat file in shell:sendto with the folowing:explorer http://localhost:8888rem check if arg is file or dirif exist "%~1\" (  php -S localhost:8888 -t "%~1") else (  php -S localhost:8888 -t "%~dp1")then for fast web testing you only have to SendTo a file or folder to this bat and it will open your explorer and run the server.

Listen on all addresses of IPv4:php -S 0.0.0.0:80Listen on all addresses of IPv6:php -S [::0]:80

To send environment variable as long as with PHP built-in web server, type like this.~$ MYENV=dev php -d variables_order=EGPCS -S 0.0.0.0:8000On PHP script we can check with this code.<?php  echo getenv('MYENV'); // print dev

I fiddled around with the internal webserver and had issues regarding handling static files, that do not contain a dot and a file extension.The webserver responded with 200 without any content for files with URIs like "/testfile".I am not certain if this is a bug, but I created a router.php that now does not use the "return false;" operation in order to pass thru the static file by the internal webserver.Instead I use fpassthru() to do that.In addition to that, my router.php can be configured to...- ... have certain index files, when requesting a directory- ... configure regex routes, so that, if the REQUEST_URI matches the regex, a certain file or directory is requested instead. (something you would do with nginx config or .htaccess ModRewrite)Maybe someone finds this helpful.================================<?php$indexFiles = ['index.html', 'index.php'];$routes = [  '^/api(/.*)?$' => '/index.php'];$requestedAbsoluteFile = dirname(__FILE__) . $_SERVER['REQUEST_URI'];// check if the the request matches one of the defined routesforeach ($routes as $regex => $fn){  if (preg_match('%'.$regex.'%', $_SERVER['REQUEST_URI']))  {    $requestedAbsoluteFile = dirname(__FILE__) . $fn;    break;  }}// if request is a directory call check if index files existif (is_dir($requestedAbsoluteFile)){  foreach ($indexFiles as $filename)  {    $fn = $requestedAbsoluteFile.'/'.$filename;    if (is_file($fn))    {      $requestedAbsoluteFile = $fn;      break;    }  }}// if requested file does not exist or is directory => 404if (!is_file($requestedAbsoluteFile)){  header($_SERVER['SERVER_PROTOCOL'].' 404 Not Found');  printf('"%s" does not exist', $_SERVER['REQUEST_URI']);  return true;}// if requested file is'nt a php fileif (!preg_match('/\.php$/', $requestedAbsoluteFile)) {  header('Content-Type: '.mime_content_type($requestedAbsoluteFile));  $fh = fopen($requestedAbsoluteFile, 'r');  fpassthru($fh);  fclose($fh);  return true;}// if requested file is php, include itinclude_once $requestedAbsoluteFile;

Built-in web server uses SAPI logging subsystem. Therefore all messages are written to standard error, and not to standard output stream.If you want to save server logs into a file, the following command will work:php -S 0.0.0.0:80 2>&1 | tee out.log