Immutability and beyond: verifying program behaviour with Psalm

September 10, 2019 by Matt Brown

As a language, PHP permits you to do basically anything. There are some built-in runtime constraints (like parameter and return types) that you can op…


Psalm 3-and-a-half

August 23, 2019 by Matt Brown

It’s been over six months since version 3.0 of Psalm was released. There have been over a thousand commits to Psalm since then, bringing all sorts o…


Announcing Psalm support for Laravel

March 5, 2019 by Matt Brown

Today I’m releasing a Psalm plugin for Laravel! Background Two months ago I announced the latest version of Psalm, and discussed how its new plugin …


Uncovering PHP bugs with @template

January 30, 2019 by Matt Brown

This guide discusses functionality available in two PHP static analysis tools: Psalm (from Vimeo), and Phan. PHPStan has plans to support templated ty…


Announcing Psalm v3

January 3, 2019 by Matt Brown

TL;DR: Psalm is a PHP static analysis tool that’s designed to improve large codebases by identifying both obvious and hard-to-spot bugs through the …


Fixing code that ain’t broken

March 16, 2018 by Matt Brown

In June of 2015, the Vimeo Codebase was large, sprawling, and full of magic. It processed many millions of requests every hour. The users were happy, …