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126 questions, 454 terms and 400 topics in 20 areas.
35 results for “Infrastructure as Code”
Infrastructure as Code
Defining infrastructure in version-controlled declarative files that a tool reconciles against the real environment.
Configuration Drift
Divergence between the infrastructure described in code and the infrastructure actually running, usually caused by manual changes.
Terraform State
The file mapping declared resources to real infrastructure, without which the tool cannot tell what it already created — and which becomes critical infrastructure in its own right.
Authorization Code Flow with PKCE
The OAuth flow recommended for all client types, in which an authorisation code is exchanged for tokens using a proof key that binds the exchange to the original requester.
Policy as Code
Expressing governance rules as executable code evaluated automatically, so compliance is prevented at creation rather than reported after the fact.
Application Performance Monitoring
Instrumentation inside the application that attributes latency and errors to specific code paths, queries and dependencies.
C4 Model
A set of four nested diagram levels — context, container, component, code — that keeps each diagram at one consistent level of abstraction.
Clean Architecture
Concentric layers with a strict dependency rule — source code dependencies point only inwards, towards higher-level policy.
Cost per Request
The fully-loaded infrastructure cost of serving one request, and the unit that makes architectural cost decisions comparable.
Dropbox's Move Off S3
Dropbox moved the majority of its file storage off Amazon S3 onto custom infrastructure, reporting savings that its S-1 filing put at roughly $75 million over two years.
Edge Function
Code executed at a CDN point of presence close to the user, in a constrained, fast-starting runtime, typically to modify or route a request before it reaches an origin.
Feature Flag
A runtime switch that decouples deploying code from releasing behaviour, so unfinished or risky work can ship dark.
Layered Architecture
Organising code into horizontal layers — presentation, application, domain, data — where each layer may only call the one beneath it.
Noisy Neighbour
One tenant or workload consuming shared resources to the detriment of others sharing the same infrastructure.
Observability
The property of being able to answer new questions about a system's internal state from its external outputs, without shipping new code.
Pilot Light
A disaster recovery posture where core data is continuously replicated and minimal infrastructure runs, with the rest provisioned only on failover.
Refactoring
Changing the internal structure of code without changing its external behaviour, in small verified steps.
SOLID
Five object-oriented design principles — single responsibility, open/closed, Liskov substitution, interface segregation, dependency inversion.
Salesforce's Metadata-Driven Multi-Tenancy
Salesforce serves every customer from shared infrastructure with a single physical schema, storing customer-specific data structures as metadata rather than as separate tables.
Secrets Management
Storing, distributing, rotating and auditing credentials so that they never live in code, images or configuration files.
Service Discovery
The mechanism by which a caller finds a currently healthy network address for a service whose instances are ephemeral.
Service Mesh
An infrastructure layer of sidecar proxies that handles service-to-service networking — mTLS, retries, timeouts, routing, telemetry — outside the application.
Slack's Cellular Migration
After repeated availability-zone-level incidents, Slack rebuilt its infrastructure into per-zone cells with the ability to drain traffic away from a failing zone in minutes.
Infrastructure as Code
Declarative infrastructure, drift, state files and rebuild-from-empty.
Code Review
Where architectural rules are enforced by people rather than by tools.
Application Performance Monitoring
Attributing latency to code paths, queries and dependencies.
C4 Model
Context, container, component and code as four separate diagrams.
Design Patterns
Reusable solutions at code level, and when they become ceremony.
Documentation Practice
Keeping documents close to the code and honest about staleness.
Enterprise Integration
Estate-wide integration strategy, standards and shared infrastructure.
Hexagonal Architecture
Ports defined by the domain, adapters supplied by infrastructure.
Network Performance
Latency floors, bandwidth-delay product, and what no code change fixes.
Schema Registry
Enforcing compatibility on events the way CI enforces it on code.
Technology Architecture
Platforms, runtimes and infrastructure standards across the estate.