Development Tools

Articles about Development Tools by Sebastian Bergmann

A glowing magnifying glass over a bug symbol, held by a hand, against a dark background of binary code and geometric patterns. A visual metaphor for the disciplined investigation of performance problems.

April 23, 2026

Debugging Performance in PHP

"It feels slow" is not a diagnosis. I explain the three disciplines that turn vague complaints into actionable data: tracing, profiling, and benchmarking.

A bouncer in a black suit, earpiece in, hand raised in a firm "stop" gesture at the door of a club. Behind him, a queue of hopeful guests waits behind a golden velvet rope. A visual metaphor for a gatekeeper deciding who gets in and who does not.

April 18, 2026

The Bouncer in the Dependency Resolver

Composer 2.9 moved security advisory enforcement from an opt-in third-party package into the resolver itself. This article walks through how the mechanism works, how it relates to the older packages it replaces, and where it can bite you.

This image shows a stylised representation of a DNA double helix, with a single section highlighted. The DNA strands are shown in blue, while a short section of the base pairs and the associated connections glow red. The imagery communicates a mutation or targeted change at the molecular level, as applied in genetic analysis, mutation testing or biotechnological processing. The focused area could symbolise a mutation, repair or targeted intervention, as used in genetic research.

November 19, 2025

Path Coverage or Mutation Testing?

How thoroughly do your tests cover the code, and how reliably do they detect real errors? I show you how to find out.

Workspace with various tools that are often used for precise manual work, model making or handicrafts

June 16, 2025

Psalm or PHPStan?

Psalm or PHPStan: which tool is the better choice for code analysis? Or is it worth combining both tools for maximum code quality?

Tool wall on which a variety of hand tools are neatly arranged

June 25, 2024

PHP_CodeSniffer or PHP-CS-Fixer?

Should PHP_CodeSniffer or PHP-CS-Fixer be used to get code "in shape"? Should both tools even be used together?

A man is sitting on a dune covered with dry grass. He appears pensive or perhaps even sad, as he rests his head on his arm with one hand while looking down.

March 22, 2024

PCOV or Xdebug?

Should you use PCOV or Xdebug to collect code coverage data? I give a personal answer.

February 15, 2017

The Death Star

I explain why using overly open version restrictions can lead to problems.

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