An example PHP & BASH Post-Receive github web hook to package projects

build.sh

#! /usr/bin/env bash

#clone the repo
git clone -q "${1}" "clones/${2}"

cd "clones/${2}"

#update the submodules (how do we handle errors here?)
git submodule --quiet update --init --recursive

cd ../../

#tar up the directory
tar --exclude=.git -cf "archives/${2}-master.tar" "clones/${2}"

#remove the cloned repo
rm -rf "clones/${2}"

echo "A new archive has been created at /archives/${2}-master.tar" | mail -s 'Github project build successul!' '[email protected]'

github.php

<?php
        error_reporting(0);

        try
        {
                // Decode the payload json string
                $payload = json_decode($_REQUEST['payload']);
        }
        catch(Exception $e)
        {
                exit(0);
        }

        // Pushed to master?
        if ($payload->ref === 'refs/heads/master')
        {
                // Log the payload object
                file_put_contents('logs/github.txt', print_r($payload, TRUE), FILE_APPEND);

                // Prep the URL - replace https protocol with git protocol to prevent 'update-server-info' errors
                $url = str_replace('https://', 'git://', $payload->repository->url);

                // Run the build script as a background process
                `./build.sh {$url} {$payload->repository->name} > /dev/null 2>&1 &`;
        }
?>

Thank you @nicolae-olariu, your file_get_contents() tip helped me fix my webhook in https://github.com/marginallyclever/Robot-Overlord. Kudos!