Deprecation of protocol version 1 - November 2025

SDKs using version 1 of Ably’s realtime protocol will be sunset on 1st November 2025.

This version was superseded by version 2 in January 2023. It introduced new functionality, with a more efficient and scalable backend implementation. New features are not available using version 1 of the protocol, nor in any SDKs implementing it.

SDK versions earlier than those listed below are now considered deprecated. If you are using a version older than those listed, upgrade before the 1st November 2025.

Product Language Versions
Pub/Sub JavaScript < 1.2.36
Pub/Sub Java < 1.2.35
Pub/Sub Swift / Objective-C < 1.2.24
Pub/Sub .NET < 1.2.12
Pub/Sub Go < 1.2.14
Pub/Sub Python < 2.0.0-beta.6
Pub/Sub Ruby < 1.2.5
Pub/Sub PHP < 1.1.9
Pub/Sub Flutter < 1.2.25
Kafka Connect < 2.1.4

Contact support if you have any questions.

On the 1st November 2025 attempts to connect to Ably using an SDK that uses version 1 of the protocol will start to fail. Failures will be phased, with only a fraction of traffic being rejected at first, until 100% of requests are rejected after several weeks.

Requests that are rejected will contain an error message and code referencing this deprecation notice and the associated deprecation policy.