API & Integration
General material on integrating systems through contracts.
15 terms in this topic
API Gateway
A single entry point in front of a set of services that handles authentication, rate limiting, routing and protocol translation.
conceptBackward Compatibility
The property that a new version of a producer continues to work with clients written against the old version.
practiceContract Testing
Verifying that a provider satisfies the expectations each of its consumers actually relies on, without running all the services together.
patternDead Letter Queue
A separate queue that receives messages which could not be processed after a set number of attempts, so they neither block the consumer nor disappear.
practiceEnterprise Integration Patterns
A catalogue of named, composable messaging patterns — router, translator, aggregator, splitter, filter, dead letter channel — that gives integration …
patternEvent-Driven Integration
Systems integrating by publishing and consuming events rather than by calling each other's APIs.
protocolGraphQL
A query language and runtime where the client specifies exactly which fields it needs, against a typed schema, usually via a single endpoint.
protocolgRPC
A contract-first RPC framework using Protocol Buffers over HTTP/2, with generated clients and servers and first-class streaming.
patternIdempotency Key
A client-generated unique value sent with a request so the server can recognise a retry and return the original result instead of acting twice.
case-studyLinkedIn and the Origin of Kafka
Kafka was built to replace point-to-point data integration between many systems with a single durable log that any system could publish to and any nu…
toolOpenAPI
A machine-readable specification format for HTTP APIs, from which documentation, clients, servers, mocks and validation can be generated.
patternRate Limiting
Bounding how many requests a caller may make in a window, to protect capacity and enforce fair use.
protocolREST
An architectural style for APIs built on resources identified by URLs, manipulated with uniform HTTP methods, and stateless requests.
case-studyStripe's API Versioning
Stripe pins each account to the API version current when it integrated and transforms requests and responses between versions internally, so integrat…
patternWebhook
An HTTP callback from a provider to a consumer-supplied URL when an event occurs, replacing polling with push.
Neighbouring topics
REST Design
Resources, uniform methods, status codes and statelessness.
No content yetGraphQL
Client-specified queries, N+1 resolution and query-cost control.
No content yetgRPC APIs
Contract-first RPC, generated clients and protobuf compatibility rules.
No content yetWebhooks
Push callbacks, signature verification, ordering and at-least-once delivery.
No content yetAPI Versioning
URL, header and account-pinned versioning, and who carries the burden.
No content yetBackward Compatibility
Which changes are safe, and how to make breakage a build failure.
No content yetContract Testing
Verifying what consumers actually rely on, without a shared environment.
No content yetAPI Documentation
OpenAPI as a machine-checked contract rather than as prose.
No content yetRate Limiting
Algorithms, shared counters, and signalling rejection properly.
No content yetIdempotency Keys
Client-generated keys stored atomically with the operation they guard.
No content yetPagination & Filtering
Offset versus cursor, stable ordering and unbounded result sets.
No content yetAPI Error Handling
Error shapes, retryability signals and machine-readable causes.
No content yetEvent-Driven Integration
Publishing facts rather than commands, and versioning event schemas.
No content yetMessage Formats
JSON, Protobuf, Avro — schema evolution and payload economics.
No content yetSchema Registry
Enforcing compatibility on events the way CI enforces it on code.
No content yetIntegration Patterns
Routers, translators, splitters, aggregators and dead letter channels.
No content yetLegacy Integration
Reaching systems that cannot change, without importing their model.
No content yetPartner & B2B Integration
External contracts, onboarding, sandboxes and long deprecation windows.
No content yetAPIs as Products
Ownership, lifecycle, deprecation policy and developer experience.
No content yet