MySQLTuner : MySQLTuner is a script written in Perl that will assist you with your MySQL configuration and make recommendations for increased performance and stabi...
Use The Index, Luke! : A tutorial covering SQL indexing and SQL tuning for developers: avoiding unnecessary details about database internals.
SQL indexing is the most effect...
Browser Calories : The easiest way to measure your performance budget.
InstantClick : InstantClick is a JavaScript library that dramatically speeds up your website, making navigation effectively instant in most cases.
WebPagetest : Run a free website speed test from multiple locations around the globe using real browsers (IE and Chrome) and at real consumer connection speeds.
Vitess is a database clustering system for horizontal scaling of MySQL.
Minimize round-trip times : An article on the best practices to apply in order to minimize HTTP round-trip times
Let's make the web faster : There are many ways to make websites run faster. In this section, you can discover performance best practices that real web professionals employ in th...
PURL : PURLs are persistent URLs, they provide permanent addresses for resources on the web.
DVWA - Damn Vulnerable Web Application : Damn Vulnerable Web App (DVWA) is a PHP/MySQL web application that is damn vulnerable. Its main goals are to be an aid for security professionals to t...
Charles Web Debugging Proxy : Charles is an HTTP proxy / HTTP monitor / Reverse Proxy that enables a developer to view all of the HTTP and SSL / HTTPS traffic between their machine...
Nice write-up on techniques for scaling up a web application.