Network Upgrade to v3.6.1: What Validators and the Community Need to Know

The Terra Classic network is preparing for an upgrade to version v3.6.1. This proposal requests validator and community approval to implement fixes and performance improvements, including a legacy contract repair that strengthens overall network stability.

If approved, the chain will halt automatically at block height 26479000, estimated for 18 December 2025 at 15:10 UTC. The exact time will depend on block speed. After the halt, validators will install the updated terrad client and resume operations.

Purpose of the Upgrade

The v3.6.1 update introduces improvements focused on network stability, compatibility, and performance. The upgrade is tagged v13_1 and must be applied at the specified block height to maintain consensus.

Upgrade Process for Validators

Validators must perform the upgrade only after the chain halts at the designated block height.

Fresh Installation

git clone https://github.com/classic-terra/core core-v3.6.1
cd core-v3.6.1
git checkout v3.6.1
make build && make install

Updating an Existing Repository

cd core
git stash
git fetch --all
git fetch --tags
git checkout v3.6.1
make build && make install

Verification:

terrad version
v3.6.1

After installation, restart the terrad client or system service and allow it to reach consensus.

Instructions for Infrastructure Providers

Providers using Mantlemint accelerated LCDs should build and install the updated Mantlemint version after the upgrade height is reached. The updated release is available in the v3.6.1 repository.

Testing and Rollback Plan

A release candidate of v3.6.1 was tested on the rebel-2 testnet on 25 November. If the mainnet cannot produce blocks after the upgrade, the upgrade name v13_1 can be applied to version v3.6.0. Validators may need to roll back to a previous state and install a patched v3.6.1 release.