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A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
Chain-of-Thought Prompting 🧠 1
A prompting technique that instructs an LLM to show its reasoning step-by-step before giving a final answer, significantly improving accuracy on complex tasks.
6mo ago AI / ML beginner
Clipboard API HTML5 🧠 1
The async Clipboard API (navigator.clipboard) is the modern replacement for document.execCommand('copy') — supports text, images, and rich content with proper permission handling.
6mo ago JavaScript beginner
Concurrency vs Parallelism 🧠 2
Concurrency is about dealing with multiple tasks at once (structuring); parallelism is actually executing multiple tasks simultaneously (hardware). You can have one without the other.
6mo ago Concurrency beginner
Correlation ID Pattern 🧠 3
A correlation ID is a unique identifier attached to every request and propagated through all logs, services, and queues — enabling end-to-end request tracing through string search.
6mo ago Observability beginner
CSS Nesting (Native)
Native CSS nesting lets you write nested selectors directly in CSS without a preprocessor — &:hover inside .card applies to .card:hover — available in all modern browsers since 2023 without any build step.
6mo ago Frontend beginner
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.
6mo ago PHP beginner
Debugging PHP PHP 5.0+ 🧠 8
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.
6mo ago PHP beginner
each() & list() — Deprecated Iteration PHP 3.0+
each() was deprecated in PHP 7.2 and removed in PHP 8 — replace while(list($k,$v)=each($arr)) with foreach. list() itself is still valid as [] destructuring.
6mo ago PHP beginner
ereg() / eregi() — POSIX Regex Removed in PHP 7 PHP 3.0+
ereg() and eregi() were POSIX regex functions removed in PHP 7.0 — replace with preg_match() (PCRE) which is faster, more powerful, and the standard since PHP 4.
6mo ago PHP beginner
Error Logging PHP 4.0+ 🧠 2
Recording application errors, exceptions, and diagnostic information to persistent storage — essential for diagnosing production issues where display_errors must be off and errors are invisible to users.
6mo ago PHP beginner
Error Reporting & Display PHP 4.0+ 🧠 1
PHP's error_reporting level and display_errors directive control which errors are shown and where — development needs E_ALL with display on; production needs E_ALL with display off and logging on.
6mo ago PHP beginner
Error.cause — Error Chaining ES2022 🧠 2
ES2022 added a cause option to the Error constructor — 'new Error('message', { cause: originalError })' — enabling proper error chaining where a high-level error wraps its underlying cause, preserving the full error context across abstraction layers.
6mo ago JavaScript beginner
Exception Handling Introduced (PHP 5) PHP 5.0+
PHP 5 introduced try/catch/finally and the Exception class — replacing PHP 4's procedural error handling with structured exception-based patterns.
6mo ago PHP beginner
File Permissions PHP 4.0+
Unix permission bits (owner/group/world read-write-execute) that control which processes can read, write, or execute files — misconfigured permissions are a common PHP deployment and security issue.
6mo ago PHP beginner
Four Golden Signals
Google SRE's Four Golden Signals — Latency, Traffic, Errors, Saturation — are the four metrics that, if monitored and alerted on, cover most production reliability concerns.
6mo ago Observability beginner
Geolocation API HTML5
navigator.geolocation provides GPS/network location data — requires HTTPS, user permission, and graceful fallback handling for denial or unavailability.
6mo ago JavaScript beginner
Global Function Style vs OOP Evolution PHP 4.0+
PHP 4's procedural global-function style evolved into PHP 5 OOP — understanding the transition explains why modern PHP has both paradigms and how to migrate legacy procedural code.
6mo ago PHP beginner
Grafana & Dashboards 🧠 1
Grafana is the de facto open-source dashboard platform — connecting to Prometheus, Loki, Elasticsearch, and 50+ data sources to visualise metrics, logs, and traces in a unified UI.
6mo ago Observability beginner
Greedy vs Lazy Quantifiers PHP 5.3+ 🧠 2
Greedy quantifiers (*, +, ?) match as much as possible; lazy quantifiers (*?, +?, ??) match as little as possible — the difference determines which text is captured when multiple matches are possible.
6mo ago Regex beginner
Health Check Patterns
Health checks report service status to load balancers and orchestrators — /health/live (is the process running?), /health/ready (can it serve traffic?), and deep health checks for dependencies.
6mo ago Observability beginner
✓ schema.org compliant