Stellar is advancing a major network upgrade known as Adapter, or Protocol 28, designed to streamline smart contract development on its Soroban platform while strengthening consensus under heavy load. The changes aim to support growing adoption and real-world financial applications without compromising the network’s transaction speed or low costs.

The upgrade centers on three Core Advancement Proposals. Two of them focus on Soroban, Stellar’s smart contract environment, while the third targets the consensus layer that keeps the blockchain synchronized.

Contract Upgrades and Data Handling Improvements

CAP-85 introduces atomic upgrades for fleets of smart contracts that share the same code. Developers can update a single shared executable reference, allowing an entire group of contracts to switch to new code at once rather than upgrading each one individually. This approach reduces the number of separate contracts that need deployment and lowers the risk of partial upgrades that leave some contracts on outdated versions.

CAP-86 adds sparse map host functions. These enable contracts to manage data structures that include missing or additional fields as applications evolve. The feature simplifies migrations and reduces compatibility problems that previously arose when contract data formats changed.

Together, the two proposals give developers more flexible tools for building, maintaining, and scaling applications on Soroban.

Consensus Performance Under Load

CAP-83 addresses performance at the consensus layer. Validators traditionally wait for a complete transaction set before proceeding. When data propagates slowly during periods of high activity, the process can stall. The upgrade allows validators to begin voting before a full set arrives and provides a mechanism to discard late or incomplete sets. The goal is to keep the network moving smoothly even as transaction volume increases, supporting Stellar’s push toward broader financial use cases.

Related improvements, including phased activation of parallel transaction-set downloading, are expected to deliver gradual performance gains after mainnet activation.

Rollout Schedule and Preparation Steps

The Adapter core stable release was issued on August 13. Supporting infrastructure and software development kit updates are scheduled for release between August 13 and August 21.

A vote to activate Protocol 28 on the Stellar testnet is set for August 27 at 17:00 UTC. If the testnet phase proceeds as planned, the mainnet vote is scheduled for September 16 at 17:00 UTC.

Operators running typical SDK-based integrations are advised to update their software before the testnet vote for test environments and before the mainnet vote for production systems. Validators, infrastructure providers, wallets, exchanges, and asset issuers have specific checklists outlined in the official upgrade guide.

The Adapter upgrade forms part of Stellar’s ongoing effort to improve developer experience and network scalability as activity on the chain continues to expand.