Terminology

2225 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 areas2225 Architecture Fundamentals77 Distributed Systems107 Data Architecture110 Cloud Architecture94 Networking88 API & Integration Architecture82 Reliability & Resilience75 Observability70 Performance & Capacity Engineering72 Security Architecture86 Cost Architecture & FinOps71 Business Architecture67 Architecture Communication67 Enterprise Architecture66 Legacy Modernization71 AI-Era Architecture74 Software Architecture & Engineering71 Architecture Patterns71 Architecture Decision-Making63 The Architect's Meta-Skills61 Delivery & Release Engineering66 Platform Engineering & Developer Experience70 Testing & Quality Architecture66 Data Platform Architecture69 Streaming & Real-Time Data69 Data Governance & Semantics74 Frontend & Experience Architecture66 Edge, Mobile & IoT68 Regulatory & Data Protection Architecture65 Assurance, Audit & Model Risk69

Kind Any concept801 practice736 pattern377 metric127 case-study77 tool62 protocol45

10 terms shown.

Term	Kind	Topic	What it is
Checkpoint Interval	metric	Stream Processing Frameworks	How often a stateful processor persists its state and offsets, which trades steady-state overhead against how much work is redone after a failure.
Completeness SLO Did Everything Arrive, Delivery Completeness	metric	Streaming SLOs	The proportion of produced events that actually reached the destination - the streaming SLO that is measured least often and whose absence conceals the most damaging failure.
Consumer Lag	metric	Streaming SLOs	The gap between the latest offset written to a partition and the offset a consumer group has processed, expressed in records or in time.
Dead-Letter Budget Diversion Budget, Poison Rate Budget	metric	Dead Letter Handling	A declared ceiling on the share and the age of records a pipeline may divert before it counts as failing rather than coping - with an owner and a defined action attached to each breach.
Feature Freshness	metric	Feature Freshness	How recent the data behind a model's input features is at the moment of inference, and the training-serving consistency problem it creates.
Feature Staleness	metric	Feature Freshness	The age of the feature values a model scores against, and the divergence between how they are computed at training time and at inference time.
Keyed State Size	metric	Stateful Stream Processing	The total state a job holds per key across all keys, which governs memory, checkpoint duration and recovery time.
Retention Cost	metric	Streaming Cost	The storage bill for keeping a log replayable, which is set by retention multiplied by throughput multiplied by the replication factor.
Watermark Lag	metric	Watermarks & Late Data	How far behind the newest event a watermark is held, which trades result latency against how much late data is included.
Window Overlap Factor Hop Multiplier, Sliding Window Fan-Out	metric	Windowing	The ratio of a sliding window's size to its advance - the number of windows each record belongs to, and therefore the multiplier on state, output volume and any naive sum taken downstream.