---
title: v6.3.0 - 2026-07-13
slug: v630-2026-07-13
docTags: 
createdAt: 2026-07-13T16:06:15.203Z
---

Release notes for Voltage Payments API release `v6.3.0`, published 2026-07-13.

- Send payment requests now accept an optional `flow_preference` of `direct` or `swap`. The field is supported for node-backed wallets with fulfillment infrastructure; when supplied, it is preserved through payment execution.
- Send payment responses and webhook payloads now include a `route` field. The route is derived from the requested flow preference, with missing or older values defaulting to `direct`.
- Payment cursor pagination is more reliable and now uses direction-aware v2 cursors while preserving legacy offset pagination and v1 cursor chains. Transient payment read timeouts or recovery conflicts return the documented `503 read_temporarily_unavailable` error.
- Payment execution now persists prepared execution artifacts so newly prepared payments can safely resume after interruptions without rebuilding or double-executing the payment. Existing historical prepared events still require reconciliation or repair.
- Lightning-to-on-chain swap funding and claim fee handling is more resilient to fragmented UTXOs, with safer locked-input reuse and fee calculation.