Ranked by the provider's API Evangelist rating — the Kin Score is scored per provider, not per API, so every API of a provider shares its band. How the rating works →

Exemplar 3 Complete, well-documented, and agent-ready

Salesforce Pub/Sub APIThe Salesforce Pub/Sub API is a gRPC-based API for publishing and subscribing to platform events, change da...87.5 Adobe I/O Events APIRegister event providers, define event metadata, subscribe webhook or journaling registrations, and ingest ...75.6 Oracle Siebel Event Pub/Sub APIEvent-driven integration framework enabling real-time communication between Siebel CRM and external systems...67.6

Strong 5 Solid coverage with minor gaps

ThingSpeak MQTT APILightweight pub/sub MQTT broker at `mqtt3.thingspeak.com` over TCP (1883), TLS (8883), WebSocket (80), and ...60.6 OCI Notifications APIPublish and subscribe messaging service for setting up communication channels using topics and subscription...60.2 IBM Event StreamsFully managed Apache Kafka service for high-throughput event streaming, event ingestion, and event stream d...60.0 Salesforce Pub/Sub APIgRPC-based API for publishing and subscribing to platform events, change data capture events, and real-time...55.3 Salesforce Pub/Sub APIgRPC-based API for publishing and subscribing to platform events, change data capture events, and custom ch...54.7

Developing 14 Usable, with meaningful gaps to close

Encore Infrastructure APIEncore's Infrastructure from Code API lets developers declare cloud infrastructure resources — PostgreSQL d...54.0 Azure Web PubSub Client and Upstream EventsAsyncAPI 2.6 description of the Azure Web PubSub client WebSocket subprotocols (json.webpubsub.azure.v1 and...51.4 Twitch Pubsub APIExtension PubSub messaging51.2 Oracle Transactional Event Queues (TxEventQ)Kafka-compatible event streaming and message queuing built into Oracle Database.50.6 Azure Event GridAzure Event Grid is a highly scalable, fully managed publish-subscribe event distribution service. It enabl...50.3 Scalar pubsub APIThe pubsub API from Scalar — 7 operation(s) for pubsub.49.4 SPAN eBus MQTT APIPublish/subscribe streaming API hosted on SPAN Panel using the Electrification Bus (eBus) integration frame...47.6 HiveMQ MQTT over WebSocketMQTT 3.x and MQTT 5 messaging endpoints exposed over WebSocket for browser and edge clients to publish and ...47.5 SAP Event Mesh APIThe SAP Event Mesh API provides access to the event brokering service within SAP Business Technology Platfo...46.2 Apache Kafka Messaging APIThe core Kafka messaging protocol for producing and consuming records to/from topics using the native Kafka...45.9 Enterprise Event SystemReal-time, pub/sub-based event streaming surface. Lets institutions and partners react to events emitted ac...45.7 Dapr PubSub APIPublish and subscribe messaging operations.42.5 NATS Messaging APIAsynchronous messaging API supporting core pub-sub, request-reply, queue groups, and JetStream persistent m...42.5 Pusher Channels APIPub/sub channels over WebSocket (client) and HTTP (server publish). Public, private, and presence channels ...40.1

Thin 14 Limited public surface area

Wazo Websocket Event Stream (wazo-websocketd)WebSocket gateway onto the Wazo internal event bus. An authenticated client subscribes to named platform ev...38.2 WIS2 Global Broker (MQTT)The WIS2 Global Broker provides an MQTT(S) publish-subscribe service that re-publishes real-time weather no...38.1 Syndica Solana RPC (WebSocket) APIStandard Solana RPC PubSub WebSocket service supporting accountSubscribe, programSubscribe, signatureSubscr...37.7 Roblox Open Cloud Messaging ServiceThe Messaging Service Open Cloud API publishes messages to a topic that running game servers can subscribe ...37.5 Sui PubSub APIThe PubSub API from Sui — 2 operation(s) for pubsub.34.2 PubNub REST APISingle REST surface for publish, subscribe (long-poll), presence, history, signal, and App Context. Pub/Sub...33.9 Apache EventMesh Messaging APIEvent-driven messaging via TCP, HTTP, and gRPC protocols. Events follow the CloudEvents specification. Supp...33.7 RabbitMQ AMQP Messaging APIAMQP 0-9-1 messaging protocol for producing and consuming messages via exchanges, queues, and bindings with...33.2 Apache Kafka REST Proxy APIThe Confluent REST Proxy provides a RESTful interface to an Apache Kafka cluster, making it easy to produce...32.8 IPFS Pubsub APIThe Pubsub API from IPFS — 4 operation(s) for pubsub.32.8 Redis REST API (Redis Stack)Redis is an in-memory data structure store used as a cache, message broker, and streaming engine. Redis Sta...32.8 Spring Data RedisEasy configuration and access to Redis from Spring applications. Provides low-level and high-level abstract...32.7 Apache Pulsar Messaging APIPulsar messaging protocol for producing and consuming messages on topics, with support for multiple subscri...32.2 MQTTOASIS standard messaging protocol for the Internet of Things. Lightweight publish/subscribe transport for r...27.3

Emerging 9 Early or largely undocumented

Nitric Topic ResourceSDK resource for declaring publish/subscribe topics for event-driven architectures. Nitric provisions the c...26.0 AblyA hosted realtime platform offering Pub/Sub Channels, Chat, Spaces, LiveObjects, LiveSync, and AI Transport...25.0 CentrifugoAn open-source language-agnostic realtime messaging server providing WebSocket, SSE, HTTP streaming, and We...25.0 MQTTA lightweight publish/subscribe protocol standardized by OASIS, designed for constrained devices and low-ba...25.0 PubNubA realtime platform offering Pub/Sub messaging, Presence detection, Chat SDKs, Functions (serverless), Even...25.0 PusherA hosted realtime API from MessageBird offering two products — Channels (pub/sub messaging) and Beams (push...25.0 Apache PulsarCloud-native, multi-tenant pub/sub and streaming platform with a tiered storage architecture (BookKeeper) t...24.4 MQTT ProtocolMQTT (Message Queuing Telemetry Transport, ISO/IEC 20922) is a lightweight pub/sub messaging protocol widel...19.9 Soketi Pusher-Compatible APIImplements the Pusher protocol (channels, private channels, presence channels, encrypted channels) for drop...15.7

Companies reaching this through an API (29)

These companies publish an API, specification or operation carrying “Pub-Sub” but do not classify their business under it. Listed unranked and kept out of the count above, because one tagged operation is not a statement about what a company does.

Score breakdown

Frequency

50.0

log-scaled weighted occurrences

Breadth

0.6

spread across providers

Quality lift

46.3

mean composite of providers using it

Cohesion

12.7

strength of nearest seed neighbor

Where this tag comes from

Provider tag21

Api tag45

Openapi tag5

Openapi op tag16

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find_cohortsEvery scored population of providers in the catalog.

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Pub-Sub

Providers using this tag (21)

APIs with this tag (45)