Realtime and Subscriptions

How each backend-as-a-service platform pushes live data updates to clients.

Supabase

Provides Realtime, a service that streams Postgres changes (via logical replication) to subscribed clients over WebSockets, alongside presence and broadcast channels for ad hoc real-time messaging.

Firebase

Both Firestore and the Realtime Database push live updates to any client listening on a query or document, which was one of Firebase’s defining, earliest features.

Appwrite

Provides realtime subscriptions over WebSockets for database, storage, and account events, letting clients react immediately to changes without polling.

Convex

Realtime is the default, not an add-on: every query function’s result is automatically kept live, and Convex re-runs and pushes updated results to every subscribed client whenever the underlying data it depends on changes.

PocketBase

Provides realtime subscriptions over Server-Sent Events for database record changes, built into the same single-binary server as everything else.

Nhost

Inherits Hasura’s GraphQL subscriptions, letting clients subscribe to live query results over WebSockets directly against the Postgres data.

AWS Amplify

Supports realtime data through AWS AppSync’s GraphQL subscriptions, pushing updates to subscribed clients over managed WebSocket connections.

Hasura

GraphQL subscriptions are one of its core features — clients subscribe to a query and receive live updates whenever the underlying Postgres data changes, without any custom pub/sub code.