Terminology

2205 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 areas2205 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 Architecture69 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 Architecture64 Streaming & Real-Time Data69 Data Governance & Semantics69 Frontend & Experience Architecture66 Edge, Mobile & IoT68 Regulatory & Data Protection Architecture65 Assurance, Audit & Model Risk64

Kind Any concept794 practice734 pattern368 metric125 case-study77 tool62 protocol45

2205 terms shown.

Term	Kind	Topic	What it is
Cell-Based Architecture Cellular Architecture, Shuffle Sharding	pattern	Cell-Based Architecture	Running many complete, independent copies of the stack, each serving a subset of users, so any failure is confined to one cell.
Centralisation Trade-off	concept	Centralised vs Distributed	The exchange between consistency and control gained by centralising a capability and the autonomy and speed retained by distributing it.
Centralised versus Distributed	concept	Centralised vs Distributed	Whether a capability should be one shared thing or many independent ones — a recurring decision whose answer changes with organisation size.
Certificate Chain Chain of Trust	concept	TLS & Certificates	The sequence from a server's certificate through one or more intermediate CAs to a root the client already trusts.
Certificate Lifecycle Management	practice	TLS & Certificates	Issuing, deploying, monitoring and renewing certificates automatically, because manual tracking reliably produces outages.
Certification and Architecture	concept	Certification Impact on Architecture	How pursuing a certification shapes architecture — mainly through scope boundaries and the need for automatic evidence.
Certification Scope Boundary	concept	Certification Impact on Architecture	The declared set of systems, locations and people a certification covers, which determines both its cost and what it actually tells a customer.
Certified Report	practice	BI Governance	A small set of reports explicitly endorsed as authoritative, with an owner and a review cadence, distinguished from everything else people have built.
Champion-Challenger Contamination Closed-Loop Evaluation Bias, Logged-Feedback Contamination	concept	Model Risk Management	The condition where a model's offline evaluation data was generated by the model it is being compared against, so the metric rewards imitation and improves while live outcomes stay flat.
Change Advisory versus Automated Gates	concept	Change Advisory vs Automated Gates	Whether change is controlled by human review or by automated verification — where the evidence favours automation and the regulation increasingly permits it.
Change Data Capture CDC	pattern	Data Architecture	Publishing a stream of a database's row-level changes by reading its replication log, without modifying the application that owns it.
Change Data Capture in Practice CDC	pattern	Change Data Capture	Turning a database's replication log into an event stream, so downstream systems learn about changes without the application publishing them.
Change Failure Rate	metric	Quality Gates	The proportion of deployments to production that cause a degradation requiring remediation.
Change Volume Ratio Update-to-Insert Ratio, Mutation Rate	metric	CDC Pipeline Design	The proportion of a change stream that is updates and deletes rather than inserts, which decides target storage design, merge cost and whether a table can be append-only.
Change-Aware Test Selection Affected Test Selection, Predictive Test Selection	practice	Pipeline Architecture	Running only the tests a change could affect, determined from a dependency graph - with periodic full runs to verify the selection itself.
Change-Reason Cohesion Single Reason to Change, Axis of Change	practice	Cohesion	The working test for a module boundary - things belong together if they change for the same reason, at the same time, driven by the same stakeholder, and share invariants.
Changelog Stream	concept	Stream-Table Duality	A stream whose records are keyed updates, so replaying it from the beginning reconstructs a table — the same information in the other of its two forms.
Chaos Engineering	practice	Reliability & Resilience	Deliberately injecting failure into a system to discover, before an incident does, which of your resilience assumptions are false.
Chaos Engineering in Practice	practice	Chaos Engineering	Deliberately injecting failure into production to verify that resilience mechanisms work — an experiment with a hypothesis, not vandalism.
Chaos Experiment	practice	Chaos as a Test	A controlled fault injected into a system to test a written hypothesis about how it should degrade.
Chaos Experiment Yield Findings per Engineer-Week, Resilience Discovery Rate	metric	Chaos as a Test	New findings per unit of resilience-engineering effort - the number that separates a chaos programme's decaying discovery value from its cheap and permanent regression value, and decides which half to fund.
Characterisation Test Golden Master Test, Approval Test, Behaviour Snapshot	practice	Application Decomposition	A test that records what a system currently does - bugs included - rather than what it should do, providing the safety net that makes changing an untested legacy system possible at all.
Chargeback and Showback	practice	Cost & FinOps	Attributing cloud cost to the teams that generate it — either informationally (showback) or by moving it onto their budget (chargeback).
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.
Choreography vs Orchestration	concept	Orchestration vs Choreography	Whether a multi-service process is driven by a central coordinator or emerges from services reacting to each other's events.
Chunk Boundary Strategy	practice	Chunking & Retrieval	How source documents are split for embedding, which determines whether retrieved passages are self-contained and coherent.
Chunk-Level Deduplication Content-Defined Chunking, Sub-File Deduplication	pattern	Storage Costs	Splitting files into content-addressed pieces at boundaries chosen by the data itself, so repeated rewrites of a large artifact store only the bytes that changed rather than a new full copy.
Chunked Prefill Prefill Splitting, Interleaved Prefill, Piecewise Prompt Processing	pattern	AI Cost Management	Breaking a long prompt's prefill into pieces interleaved with other sequences' decode steps, so that one enormous request cannot stall every in-flight interactive response.
CI Secret Exposure Surface Build Credential Blast Radius, Runner Secret Surface	concept	Supply Chain Security	The set of credentials reachable by any code that executes in a build job, which is usually far larger than the job needs and is exposed in full by a single compromised step.
CI/CD Continuous Integration, Continuous Delivery	practice	CI/CD	Integrating continuously and keeping the software always releasable — a discipline about batch size, with automation as its enabler.
CIDR Planning	practice	VPC Design	Allocating non-overlapping address ranges across an estate in advance, because ranges cannot be resized and overlaps prevent connectivity.
Circuit Breaker	pattern	Distributed Systems	A proxy that stops calling a failing dependency after a failure threshold, failing fast instead, and periodically tests whether it has recovered.
Circuit Breakers in Practice Failure Detector, Trip Switch	pattern	Circuit Breakers	What a breaker is actually for, the configuration that stops it causing the outage it prevents, and why Netflix moved away from static thresholds.
Circular Observability Dependency Blind Spot Cycle, Self-Observing Stack, Telemetry Co-Failure	concept	Failure Modes	When the tooling used to diagnose a failure runs on the infrastructure that is failing - so the outage removes the ability to see the outage, converting a technical problem into a search problem.
Claim Provenance As-Of Metadata, Source-Tagged Data	practice	Data Architecture	Storing every externally sourced value with its timestamp, its source and a confidence derived from that source's history - so that downstream decisions about staleness are explicit rather than accidental.
Claim-Code Binding Device Claiming, Ownership Binding, Claim on First Use	pattern	Device Provisioning	Giving a device its cryptographic identity at manufacture but its owner at first use, so the factory line never depends on the cloud and ownership can be transferred without re-keying.
Classification Propagation Label Inheritance, Lineage-Aware Classification, Derived Sensitivity	practice	Sensitivity Labelling	Carrying a column's sensitivity classification through every derived table, view and export, so that copying restricted data into an aggregate does not silently strip its protection.
Classification Propagation Labels Travelling Through Lineage, Derived-Data Sensitivity	practice	Sensitivity Labelling	Carrying a sensitivity label through every derivation, so a restricted column copied into an aggregate, a training set or an export remains subject to its controls.
Clean Architecture Onion Architecture	pattern	Clean Architecture	Concentric layers with dependencies pointing inward, so business rules know nothing about frameworks, databases or delivery mechanisms.
Client Feature Flags	practice	Client Feature Flags	Flags evaluated in a browser or mobile app — where the constraints of distribution, caching and offline behaviour make them meaningfully harder than server flags.
Client Request Waterfall Fetch Waterfall, Client-Side N Plus One	concept	API Shapes for UI	A chain of requests where each one can only start after the previous response arrives, so the screen's load time is set by the depth of the chain times the round trip rather than by bandwidth.
Client Runtime Constraint	concept	Frontend & Experience Architecture	The properties of the browser or device you do not control — CPU, network, version, extensions — which make the client a distributed system component rather than a rendering surface.
Client State Architecture	practice	Client State Architecture	Separating server state, client state and URL state — the distinction that removes most frontend complexity.
Client-Side Data Layer Query Cache, Server State Management	pattern	Client Caching & Data Layer	A client library that owns fetching, caching, invalidation and background refresh of server data, distinct from local UI state.
Client-Side Discovery	pattern	Service Discovery	The caller queries the registry itself and chooses an instance, rather than sending to a stable address that something else resolves.
Client-Specific Aggregation	pattern	Backend for Frontend	A dedicated backend per client type that shapes and combines downstream data for that client's needs, owned by the client team.
Clock Drift	concept	Physical-World Failure Modes	Device clocks diverging from real time, which corrupts ordering, expires certificates early or late, and produces data that appears to arrive from the past.
Clocks and Ordering Logical Clocks, Happens-Before	concept	Clocks & Ordering	Why wall-clock timestamps cannot order events across machines, and the mechanisms that can.
Cloud Databases	concept	Cloud Databases	Managed and cloud-native database services — where the operational relief is real, and where the abstraction leaks.
Cloud Disaster Recovery	practice	Disaster Recovery	Designing and rehearsing recovery from the loss of a zone, a region or a provider — where the plan is worth exactly as much as its last test.
Cloud Egress Cost	concept	Network & Egress Costs	The asymmetric pricing where data entering a cloud is free and data leaving is charged, which shapes architecture more than most teams expect.
Cloud Exit Plan	practice	Multi-Cloud	A documented, costed assessment of what leaving a provider or service would require — increasingly a regulatory expectation and a better lock-in control than portability itself.
Cloud Governance	practice	Cloud Governance	The account structure, identity model, guardrails and cost attribution that make a cloud estate operable by many teams without becoming ungovernable.
Cloud Migration	practice	Cloud Migration	Moving workloads to the cloud — where the strategy per workload matters more than the programme, and where lift-and-shift produces the bill that discredits the whole effort.
Cloud Pricing	concept	Cloud Pricing Models	How cloud providers charge, which dimensions dominate, and the pricing structures that reward architectural rather than operational responses.
Cloud Pricing Models	concept	Cost & FinOps	The purchase options for cloud compute — on-demand, committed use, and spot — which differ by up to 90% for identical hardware.
Cloud Storage	concept	Cloud Storage	Object, block and file storage — with different durability, latency and cost models, and an egress bill that shapes architecture more than most designs admit.
Cloudflare 2019: One Regex, Global Outage Cloudflare WAF Outage	case-study	Load Shedding	A firewall rule containing a regular expression with catastrophic backtracking consumed CPU across Cloudflare's entire global network within seconds of deployment.
Cloudflare Workers: Isolates Instead of Containers V8 Isolates	case-study	Edge Functions	Running thousands of tenants per process using V8 isolates rather than containers, trading runtime flexibility for near-zero cold start and extreme density.
Cloudflare: Every Server Runs Every Service Homogeneous Edge	case-study	Cluster Architecture	Rather than dedicating machines to roles, Cloudflare runs the full software stack on every server in every location, which turns capacity into a single fungible pool.