Beginner terms
DateTimeImmutable vs DateTime
PHP 5.5+
DateTimeImmutable returns a new object for every modification — the original is never changed. DateTime modifies in place. Prefer DateTimeImmutable in all new code to avoid subtle bugs where shared date objects are accidentally mutated.
3mo ago
php beginner
Debugging PHP
PHP 5.0+
9
Systematic techniques for finding and fixing PHP bugs — from var_dump and error logs to Xdebug step-debugging, with the guiding principle of narrowing down where incorrect behaviour first appears.
3mo ago
php beginner
Division by Zero & DivisionByZeroError
PHP 7.0+
PHP 7+ throws DivisionByZeroError for intdiv() and modulo with zero — but the / operator returns false or INF instead of throwing.
3mo ago
php beginner
DOM Manipulation
ES5
1
querySelector, createElement, innerHTML — reading and modifying PHP-rendered HTML from JavaScript.
3mo ago
javascript beginner
Dict & Set Comprehensions
Python 2.7+
Python's concise syntax for building dicts, sets, and lists in a single expression — replacing verbose for-loop accumulation patterns.
3mo ago
python beginner
Date / Time Functions
PHP 5.5+
PHP's date/time API including DateTime, DateTimeImmutable, and DateTimeZone for safe, timezone-aware date handling.
3mo ago
php beginner
Dead Code
PHP 5.0+
Code that can never be executed — unreachable after a return, or inside a condition that is always false.
3mo ago
quality beginner
Deep Nesting
PHP 5.0+
3
Code indented 3+ levels deep — guard clauses and early returns can flatten most deep nesting.
3mo ago
style beginner
Denial of Service (DoS)
PHP 5.0+
An attacker overwhelms a system with requests or exploits resource-exhaustion bugs to make it unavailable to legitimate users.
CWE-400 OWASP A5:2021
3mo ago
security beginner
7.5
Deprecated & Removed PHP Functions
PHP 5.0+
Functions removed or deprecated in modern PHP versions — using them triggers errors or silent failures in new runtimes.
3mo ago
php beginner
Destructuring & Spread (JS)
ES2015 Destructuring extracts values from arrays/objects into variables; spread (...) expands iterables — both core to modern JavaScript style.
3mo ago
javascript beginner
Developer Experience (DX)
The quality of a developer's interactions with tools, APIs, documentation, and processes — good DX reduces friction, speeds onboarding, and increases productivity.
3mo ago
general beginner
DevOps
1
A culture and set of practices that unifies development and operations teams to deliver software faster and more reliably.
3mo ago
devops beginner
Directory Listing Enabled
PHP 5.0+
A web server configured to show directory contents exposes file structure and sensitive files to unauthenticated visitors.
CWE-548 OWASP A5:2021
3mo ago
security beginner
5.3
Documentation as Code
Treating documentation with the same discipline as code — version controlled, reviewed in pull requests, tested for accuracy, and kept close to the code it describes.
3mo ago
general beginner
Duplicate Code
PHP 5.0+
Identical or near-identical blocks of code in multiple places — the most common source of maintenance bugs.
3mo ago
quality beginner
DRY Principle
PHP 5.0+
Don't Repeat Yourself — every piece of knowledge should have a single, unambiguous representation in the codebase.
3mo ago
quality beginner