OS X custom Apache launch daemon (/Library/LaunchDaemons/).

com.company.launchd.apache2.plist

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
  <key>Label</key>
	<string>com.company.launchd.apache2</string>
	<key>ProgramArguments</key>
	<array>
		<string>/usr/local/apache2/bin/apachectl</string>
		<string>start</string>
	</array>
	<key>RunAtLoad</key>
	<true/>
</dict>
</plist>

to_install.sh

#!/bin/sh

# unloading current apache (system)
sudo launchctl unload -w /System/Library/LaunchDaemons/org.apache.httpd.plist

sudo chown root:wheel /Library/LaunchDaemons/com.company.launchd.apache2.plist

# loading our custom apache
sudo launchctl load -w /Library/LaunchDaemons/com.company.launchd.apache2.plist

SO cross-reference: http://superuser.com/questions/601274/how-can-i-start-an-custom-installed-apache-at-boot-in-osx