Intermediate terms
OAuth 2.0
An authorisation framework that lets users grant third-party applications limited access to their resources without sharing passwords — using short-lived access tokens issued via defined flows for different client types.
CWE-287 OWASP A7:2021
2mo ago
security intermediate
OAuth 2.0 PKCE — Proof Key for Code Exchange
PHP 7.0+ An OAuth 2.0 extension that prevents authorisation code interception attacks in public clients (SPAs, mobile apps) by binding each authorisation request to a cryptographic secret the client generates.
3mo ago
cryptography intermediate
Object.freeze / Object.seal
ES5
Object.freeze() prevents all property changes (add/modify/delete), Object.seal() prevents add/delete but allows modification — both are shallow, not deep.
3mo ago
javascript intermediate
OLAP vs OLTP
OLTP (Online Transaction Processing) optimises for many small, fast read/write operations — your main application database. OLAP (Online Analytical Processing) optimises for few, large analytical queries scanning millions of rows — your reporting and analytics database.
3mo ago
database intermediate
Opaque Objects & GdImage/CURLHandle
PHP 8.0+
PHP 8.0 replaced resource types (gd, curl, xml) with opaque objects — GdImage, CurlHandle, XMLParser — improving type safety and OOP integration.
3mo ago
php intermediate
OPcache Internals — How Bytecode Caching Works
PHP 5.5+
OPcache compiles PHP source files to bytecode once and stores the result in shared memory — subsequent requests skip parsing and compilation entirely, making PHP 5–10x faster for I/O-bound workloads.
3mo ago
php intermediate
OpenTelemetry
2
OpenTelemetry (OTel) is the open standard for telemetry — a vendor-neutral SDK for traces, metrics, and logs that exports to any backend (Jaeger, Datadog, Honeycomb, Prometheus).
3mo ago
observability intermediate
Optimistic Locking
2
Optimistic locking detects conflicts at commit time using a version number — no locks held during the transaction, high throughput for low-contention scenarios.
3mo ago
concurrency intermediate
OWASP API Security Top 10
The OWASP API Security Top 10 lists the most critical API vulnerabilities — a separate list from the web application Top 10, covering risks specific to REST, GraphQL, and other API surfaces such as broken object-level authorisation and unrestricted resource consumption.
3mo ago
security intermediate
Object Cloning & Security Implications
PHP 5.0+
clone creates a shallow copy — nested objects are still shared references. Implement __clone() for deep copy and audit what sensitive state gets duplicated.
3mo ago
security intermediate
Out of Memory Errors (memory_limit)
PHP 5.0+
PHP enforces memory_limit in php.ini — exceeding it triggers a fatal E_ERROR that cannot be caught with set_error_handler().
3mo ago
php intermediate
On-Call Culture & Runbooks
Sustainable on-call practices — fair rotation, blameless postmortems, actionable alerts, and well-maintained runbooks that reduce mean time to recovery and prevent burnout.
3mo ago
devops intermediate
OPcache Tuning
PHP 5.5+ OPcache stores compiled PHP bytecode in shared memory, eliminating recompilation on every request — proper tuning is the single highest-impact PHP performance configuration.
3mo ago
php intermediate
OpenID Connect (OIDC)
PHP 7.0+
1
An identity layer on top of OAuth 2.0 — while OAuth 2.0 handles authorisation (access to resources), OIDC adds authentication (who the user is) via the ID token.
3mo ago
networking intermediate
OAuth 2.0
PHP 7.0+
1
An authorisation framework that allows applications to obtain limited access to user accounts on third-party services without exposing passwords.
3mo ago
networking intermediate
Object Storage
PHP 5.0+ A flat-file storage system (S3, GCS, Azure Blob) where files are stored as objects with metadata and accessed via HTTP — infinitely scalable, separate from application servers.
3mo ago
cloud intermediate
Observability (Logs, Metrics, Traces)
PHP 5.0+
The ability to understand a system's internal state from its external outputs — built on three pillars: logs, metrics, and distributed traces.
3mo ago
devops intermediate
Observer Pattern
PHP 5.0+
1
Defines a one-to-many dependency so that when one object changes state, all its registered observers are notified automatically.
3mo ago
general intermediate
Opcode Caching
PHP 5.5+
2
Storing precompiled PHP bytecode in memory to skip the parse-and-compile phase on subsequent requests.
3mo ago
performance intermediate
Open Source Dependency Risk
Third-party packages introduce supply-chain attack surface — malicious code, abandoned maintainers, and known CVEs can all compromise your application.
CWE-1395 OWASP A6:2021
3mo ago
security intermediate