Intermediate terms
Structural Subtyping with Protocol
Python 3.8+
1
Protocol classes define structural interfaces — any class with matching methods satisfies the protocol without explicit inheritance (type-safe duck typing).
6mo ago
Python intermediate
Systemd Services & Unit Files
Systemd is the init system managing service lifecycle on modern Linux — unit files define how services start, stop, restart, and depend on each other.
6mo ago
Linux intermediate
Safe Database Migration Patterns
PHP 5.0+ Expand-contract, backward-compatible migrations run alongside a zero-downtime deploy — never rename or drop columns in the same deploy as the code change.
6mo ago
Database intermediate
SameSite Cookie Attribute
PHP 7.3+
3
A cookie attribute controlling whether the browser sends a cookie with cross-site requests, providing strong CSRF mitigation.
CWE-352 OWASP A1:2021
6mo ago
Security intermediate
SAST vs DAST vs IAST
PHP 5.0+
2
Three automated security testing approaches: SAST analyses source code without running it, DAST attacks a running app from outside, IAST instruments the app from within during testing.
6mo ago
Security intermediate
Searching Algorithms
PHP 5.0+
1
Linear search is O(n) and works on any array. Binary search is O(log n) but requires a sorted array. Hash lookup is O(1) and the right choice for most in-memory searches.
6mo ago
Algorithms intermediate
Secret Rotation
3
The practice of periodically replacing cryptographic secrets, API keys, and credentials — limiting the window of exposure if a secret is compromised without triggering a breach.
6mo ago
DevOps intermediate
Secrets Management
1
Storing, distributing, and rotating credentials securely — using dedicated tools rather than .env files in version control or hardcoded values in source code.
6mo ago
Security intermediate
Security by Design
PHP 5.0+
4
Integrating security requirements into software architecture and design from the very beginning, rather than bolting it on afterwards.
OWASP A5:2021
6mo ago
Security intermediate
serialize() / unserialize()
PHP 5.0+
PHP's native serialisation functions can trigger arbitrary code execution via magic methods when deserialising untrusted data.
CWE-502 OWASP A8:2021
6mo ago
PHP intermediate
9.8
Serverless Functions
PHP 7.4+
2
Event-triggered, stateless functions managed by a cloud provider — you deploy code, the provider handles servers, scaling, and availability.
6mo ago
Cloud intermediate
Service Locator Anti-Pattern
1
A class that fetches its own dependencies from a global registry — hiding them from the constructor signature and making dependencies implicit, untestable, and hard to trace.
6mo ago
Architecture intermediate
Session Riding
PHP 5.0+
An alternative term for CSRF — the attacker 'rides' the victim's authenticated session to perform actions on their behalf.
CWE-352 OWASP A1:2021
6mo ago
Security intermediate
8.1
session_regenerate_id()
PHP 5.0+
Generates a new session ID after login — the primary defence against session fixation attacks.
6mo ago
PHP intermediate
Shared Responsibility Model
The division of security responsibilities between the cloud provider and the customer — the provider secures the infrastructure; the customer secures what runs on it.
6mo ago
Cloud intermediate
Shell Pipes & Redirects
Pipes (|) connect stdout of one command to stdin of another; redirects (<, >, >>) send stdin/stdout to files — the foundation of composable Unix command-line workflows.
6mo ago
Linux intermediate
Shotgun Surgery
A single change requires making many small edits across many different classes — a sign of poor cohesion.
6mo ago
Code Quality intermediate
Side Effects
2
Observable changes a function makes beyond returning a value — modifying global state, I/O, mutation of arguments — that make code harder to reason about.
6mo ago
Code Quality intermediate
Singleton (Anti-Pattern)
1
A class that restricts instantiation to a single instance — widely considered an anti-pattern due to hidden global state and testability issues.
6mo ago
General intermediate
SLA / SLO / Error Budgets (SRE)
1
SLA is the external promise; SLO is the internal target; error budget is the allowed downtime — together they guide reliability decisions.
6mo ago
DevOps intermediate