Intermediate terms
Regex Flags & Modifiers
PHP 5.3+
4
PCRE modifiers in PHP — i (case-insensitive), m (multiline), s (dotall), x (verbose), u (Unicode) — and their inline equivalents (?imsx).
3mo ago
regex intermediate
Regex with grep, sed & awk
Three essential Linux text processing tools — grep for filtering lines, sed for stream editing, awk for field-based processing — all using regular expressions.
3mo ago
linux intermediate
Regular Expressions in JavaScript
ES2015
JS regex syntax, flags (g, i, m, s, u, d), methods (test, match, matchAll, replace, split), and the critical differences from PHP's PCRE.
3mo ago
javascript intermediate
Removed PHP Function
PHP 7.0+
2
Calling a function removed in a newer PHP version — causes a fatal error on upgrade and blocks modernisation of the PHP runtime.
3mo ago
php intermediate
Resource Prefetching
HTML5
dns-prefetch, preconnect, preload, and prefetch hints — fetching critical resources early to reduce perceived load time.
3mo ago
performance intermediate
Responsive Design Patterns
CSS3
Layout patterns for adapting UI across screen sizes — fluid grids, the column drop pattern, layout shifter, mostly fluid, and off-canvas navigation.
3mo ago
mobile intermediate
Responsive Images
HTML5
Serving different image sizes to different devices using srcset and sizes — preventing mobile devices from downloading desktop-sized images.
3mo ago
frontend intermediate
RabbitMQ
PHP 7.0+ A message broker implementing AMQP — producers publish to exchanges, exchanges route to queues, consumers pull from queues — providing durable, reliable message delivery.
3mo ago
messaging intermediate
Rainbow Table
PHP 5.5+
A precomputed lookup table mapping hash values back to their original inputs — used to crack unsalted password hashes.
3mo ago
general intermediate
random_bytes()
PHP 7.0+
1
Generates cryptographically secure random bytes from the OS entropy source — use for tokens, salts, and nonces.
3mo ago
php intermediate
Read Replicas & Database Scaling
PHP 5.0+
Directing read queries to replica servers while writes go to the primary — a simple way to scale read throughput horizontally without sharding.
3mo ago
performance intermediate
Readonly Classes (PHP 8.2)
PHP 8.2+
2
Marking an entire class readonly automatically makes all its declared properties readonly, simplifying immutable value object creation.
3mo ago
php intermediate
Readonly Properties (PHP 8.1)
PHP 8.1+
2
Properties declared with readonly can only be initialised once and then never modified, enforcing immutability at the language level.
3mo ago
php intermediate
Real User Monitoring (RUM)
ES2015
Collecting performance and error data from actual user browsers in production — capturing real-world conditions that synthetic lab testing cannot reproduce.
3mo ago
observability intermediate
realpath()
PHP 5.0+
2
Resolves a path to its canonical absolute form, collapsing ../ sequences — used to prevent path traversal.
3mo ago
php intermediate
Rector — Automated PHP Upgrades & Refactoring
PHP 7.1+
6
Rector applies rule-based AST transformations to upgrade PHP versions, migrate frameworks, and enforce coding patterns — automatically.
3mo ago
style intermediate
Recursion Patterns
PHP 5.0+ Functions that call themselves with smaller inputs — powerful for tree traversal, divide-and-conquer, and mathematical sequences, but requiring careful base cases and stack depth management.
3mo ago
algorithms intermediate
Redis Patterns (Pub/Sub, Sorted Sets, Lua)
PHP 5.0+
Beyond key-value caching, Redis enables queues, leaderboards, rate limiting, pub/sub messaging, and distributed locks via its rich data structures.
3mo ago
performance intermediate
ReDoS (Regex Denial of Service)
A crafted input causes a regex with catastrophic backtracking to consume excessive CPU, making the application unresponsive.
CWE-1333 OWASP A5:2021
3mo ago
security intermediate
7.5
Refused Bequest
A subclass that inherits methods it doesn't need or want, signalling a misused inheritance relationship.
3mo ago
quality intermediate