[Standard] Stacks Mainnet and Testnet - API upgrade to v9.3.0

Scheduled for Sep 29, 00:00 - 06:00 UTC

Scheduled

We are upgrading our Stacks Mainnet and Testnet API to v9.3.0. This release introduces a new staking cycle endpoint, removes obsolete microblock support, and includes several bug fixes for PoX cycle handling and post condition serialization.

Brief interruptions to RPC availability may occur during the maintenance window.

RPC Changes:
- /extended/v3/staking/cycles/:cycle_number — New endpoint to retrieve staking summary data for a given PoX cycle number.
- v3 transaction responses — post_condition_mode field is now correctly serialized in responses.
- PoX cycle handling — Fixed treatment of STX lock rollovers under PoX-5 and corrected in-progress cycle staked STX calculation at cycle start.
- Bond distribution events — Now include calculation_height and reward_cycle fields in responses.
- URL parameter length — Router maximum URL parameter length has been increased to support longer query strings.
- Microblock support — Microblock ingestion and unanchored data support have been completely removed; endpoints and methods relying on microblock data are no longer available.

https://github.com/hirosystems/stacks-blockchain-api/releases/tag/v9.3.0
Posted Sep 15, 2026 - 19:52 UTC
This scheduled maintenance affects: Stacks (Mainnet — REST API, Testnet — REST API).