> ## Documentation Index
> Fetch the complete documentation index at: https://docs.chainstack.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Chainstack Self-Hosted v2.64.0: September 22, 2026

> Prepares Avalanche, World Chain, and Mantle deployments for mandatory mainnet hardforks, adds Plasma Aquila upgrade support ahead of its mainnet activation, and updates client images with a security fix and compatibility improvements across the catalog.

Prepares Avalanche, World Chain, and Mantle deployments for mandatory mainnet hardforks, adds Plasma Aquila upgrade support ahead of its mainnet activation, and updates client images with a security fix and compatibility improvements across the catalog.

## Mandatory hardfork readiness

Avalanche, World Chain, and Mantle deployments now run client versions required for the Helicon, Karst, and Elysium hardforks. Avalanche's Helicon hardfork activates on mainnet today, September 22, 2026, at 15:00 UTC, and nodes not upgraded beforehand will diverge from the network.

## Plasma Aquila upgrade

Plasma deployments now configure the Aquila protocol upgrade automatically. Aquila has already activated on Plasma testnet and activates on Plasma mainnet at block 33,300,000.

## Breaking RPC changes

Avalanche removes the admin, warp, and personal JSON-RPC namespaces and several debug methods, OP Stack's optimism\_syncStatus drops cross\_unsafe\_l2, and Starknet's pathfinder now disconnects WebSocket clients that stop answering keepalive pings.

## Improvements and fixes

* Fixes a deposit-transaction security issue on OP Stack reth clients.
* Updates Sui, Arbitrum, Starknet, TRON, Sonic, Tempo, and Solana client images for compatibility and reliability.

## Component versions

| Component          | Version |
| ------------------ | ------- |
| cp-ui              | v3.13.0 |
| cp-deployments-api | v1.44.0 |
| cp-workflows       | v3.46.0 |
| cp-auth            | v0.5.1  |
| cp-bolt            | v1.13.0 |