Protocol 23 Upgrade Guide

This guide is designed to help businesses and developers prepare for Protocol 23 with key dates, release information, a changelog, and more.

You can read all about what's included in Protocol 23 in the Announcement blog and stay up to date on any and all Protocol 23-related announcements on the Stellar Developer Discord, where the ecosystem coordinates and shares information about the upgrade.

Key dates

• June 30: Testnet upgrade.
• July 17: Stable builds of all software available.
• August 14: Mainnet upgrade vote.

TL;DR: Before the upgrade, make sure to install up-to-date versions of any and all Stellar-related software you use.

If you use a Stellar SDK

For your Testnet integration, upgrade to the latest version of the relevant Stellar SDK before June 30.

For your Mainnet integration, upgrade to the latest version of relevant Stellar SDKs before August 14.

Note that some SDK maintainers publish release candidate (i.e., RC) versions of the SDK when Stellar Core, Horizon, and RPC release RC versions rather than immediately releasing stable versions. In this case, remember to upgrade to stable versions of the SDK when they are available.

We will update the releases section below to indicate when an SDK release with Protocol 23 support is available, so check back if an SDK you use isn’t listed yet.

If you run Stellar infrastructure

If you use Docker images, pull the Protocol 23 builds from the Docker registry. If you build from source or our Debian packages, make sure to also update your stellar-core, stellar-horizon, and stellar-rpc binaries to the Protocol 23 builds.

If you don’t run your own infrastructure but still need access to a Horizon or RPC instance, you can use an infrastructure provider. Here are lists for Horizon and RPC.

If you run a validator

The Protocol 23 upgrade vote is scheduled for August 14, 2025 at 1700 UTC. Here’s the command to arm your nodes for the upgrade:

upgrades?mode=set&upgradetime=2025-08-14T17:00:00Z&protocolversion=23

To view current network settings, see a history of protocol upgrades, and see pending proposals for future upgrades, take a look at https://stellar.expert/explorer/public/protocol-history

Stellar RPC rebrand

Soroban RPC was officially renamed to Stellar RPC in Protocol 22. While it has continued to be published under both names, starting in Protocol 23 soroban-rpc images and packages will no longer be available.

Below are up-to-date links to all available releases relevant to Protocol 23. In general, please make sure to check release notes for specific instructions and requirements, and unless otherwise indicated, opt for the “Latest Release.”

Stellar infrastructure

• Stellar Core
• Horizon
• Stellar RPC

SDKs

• JavaScript Base
• JavaScript SDK
• Go SDK
  • horizonclient & txnbuild
  • rpcclient
• Java
• Python
• iOS
• PHP
• C# .NET
• Flutter
• Elixir Stellar SDK