Terminology

991 terms, tools, patterns and metrics an architect is expected to use precisely. Each one gets a short explanation of what it is, and — where it matters — what it is commonly confused with. Search filters as you type; the column headers sort.

All areas991 Architecture Fundamentals38 Distributed Systems73 Data Architecture71 Cloud Architecture55 Networking51 API & Integration Architecture45 Reliability & Resilience40 Observability33 Performance & Capacity Engineering34 Security Architecture50 Cost Architecture & FinOps30 Business Architecture28 Architecture Communication27 Enterprise Architecture27 Legacy Modernization27 AI-Era Architecture34 Software Architecture & Engineering37 Architecture Patterns34 Architecture Decision-Making30 The Architect's Meta-Skills27 Delivery & Release Engineering20 Platform Engineering & Developer Experience20 Testing & Quality Architecture20 Data Platform Architecture20 Streaming & Real-Time Data20 Data Governance & Semantics20 Frontend & Experience Architecture20 Edge, Mobile & IoT20 Regulatory & Data Protection Architecture20 Assurance, Audit & Model Risk20

Kind Any concept379 practice294 pattern166 metric55 tool36 protocol35 case-study26

20 terms shown.

Term	Kind	Topic	What it is
Arrival Rate Model	concept	Performance Test Design	Driving a load test by requests arriving per second regardless of how the system responds, rather than by a fixed number of virtual users.
Automated Accessibility Coverage	metric	Accessibility Testing	The proportion of accessibility criteria a tool can decide mechanically — around a third — and the explicit acknowledgement that the rest needs people.
Consumer Contract	concept	Consumer-Driven Contracts	A machine-readable record of exactly which parts of a provider's response one consumer relies on, generated from that consumer's own tests.
Contract Verification Gate	practice	Contract Testing at Scale	A provider's pipeline stage that replays every consumer's recorded expectations and fails the build if any would break.
Definition of Done	practice	Quality Gates	The agreed, explicit conditions under which work is finished, which functions as a quality gate only when it is automated and non-negotiable.
End-to-End Test Cost Curve	concept	End-to-End Test Economics	How the cost of a broad end-to-end suite grows with its size while its marginal value falls, and where the two cross.
Mutation Score	metric	Mutation Testing	The proportion of deliberately introduced faults that the test suite detects — a measure of whether tests would notice a defect, unlike coverage.
Non-Functional Acceptance	practice	Non-Functional Test Strategy	Treating quality-attribute targets as acceptance criteria with automated verification, so a release can fail on latency the way it fails on a broken feature.
Production Parity Gap	concept	Environment Parity	The enumerated list of ways a pre-production environment differs from production, which is the list of defect classes it cannot catch.
Service Stub Fidelity	concept	Service Virtualisation	How faithfully a stand-in dependency reproduces the real one's behaviour — including its errors, latency and limits — which bounds what testing against it proves.
Shift-Left Security	practice	Security Testing in the Pipeline	Moving security checks earlier so findings arrive while the author still has context, on the condition that the signal-to-noise ratio justifies it.
Steady-State Hypothesis	concept	Chaos as a Test	The measurable statement of normal behaviour that a chaos experiment predicts will hold while a fault is injected, without which the exercise is not a test.
Synthetic Data Fidelity	concept	Synthetic Data	How closely generated data reproduces the shape, distribution and awkwardness of the real thing, which decides what the data can validly be used for.
Synthetic Monitoring	practice	Testing in Production	Continuously executing a real user journey against production from outside it, so a broken journey is detected before a user reports it.
Test Data Provisioning	practice	Test Data Management	Getting each test the data it needs, in a state it can rely on, without copying production personal data into a weaker environment.
Test Double Boundary	concept	Integration Test Boundaries	The line inside a test between what is real and what is substituted, which determines exactly what the test can and cannot prove.
Test Quarantine	practice	Flaky Test Management	Moving an intermittently failing test out of the blocking suite into a tracked, owned backlog, so a red build keeps meaning something.
Test Strategy Altitude	concept	Testing & Quality Architecture	Deciding which risks are verified at which level, so that each layer tests something the layers below it structurally cannot.
Testability as a Design Property	concept	Test Architecture Strategy	How cheaply a system's behaviour can be observed and controlled, which is decided by architecture and largely fixed before any test is written.
Testing Trophy	concept	Test Pyramid Shapes	A distribution weighted towards integration tests rather than unit tests, appropriate where most of the risk lives at boundaries rather than in logic.