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...
SPOFCheck : A CLI tool for detecting frontend SPOF, mainly blocking scripts and CSS
Pyroscope : Pyroscope is an open source continuous profiling platform. It will help you:
Find performance issues in your code
Resolve issues with high CPU utiliz...
ESBench : Shareable JavaScript Benchmarking
Built-in ES2015 support, powered by Babel
Statistically significant benchmarks, powered by Benchmark.js
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...
webhint : webhint is a linting tool that will help you with your site's accessibility, speed, security and more, by checking your code for best practices and co...
Web Developer : The Web Developer extension adds various web developer tools to a browser. The extension is available for Chrome, Firefox and Opera, and will run on a...
Nice write-up on techniques for scaling up a web application.