Fiber Dev Log 2026-03-05

[jjyr]

Updates

Features

Fiber v0.7.1 release

Links: Full changelog, Release page

• Configurable CORS: Make CORS configurable and disabled by default by @Copilot in Make CORS configurable and disabled by default #1121
• Smarter Payment Routing: Early-fail with InsufficientBalance when outbound liquidity cannot cover payment amount by @Copilot in Early-fail with InsufficientBalance when outbound liquidity cannot cover payment amount #1133
• TLC Cancellation Fix: fail pending TLCs when a hold invoice is cancelled (cancel_invoice does not remove or fail corresponding TLCs (hold invoice) #1135) by @doitian in fix: fail pending TLCs when a hold invoice is cancelled (#1135) #1138
• Duplicate Payment Prevention: reject Received in SettleTlcSetCommand to prevent duplicate same-invoice payments by @doitian fix: reject Received in SettleTlcSetCommand to prevent duplicate same-invoice payments #1137
• Observable Channel Opening: Add observable channel opening: persistent state, failure details, and only_pending filter for list_channels by @Copilot Add observable channel opening: persistent state, failure details, and only_pending filter for list_channels #1134

Improvements & Fixes

• TLC settlement reliability fixes
  • Merged two fixes to harden SettleTlcSet handling and avoid duplicate or dangling TLC states in invoice-related flows.
  • PRs:fix: reject Received in SettleTlcSetCommand to prevent duplicate same-invoice payments #1137, fix: fail pending TLCs when a hold invoice is cancelled (#1135) #1138
• Persisted commitment state for TLC reestablish flow
  • In restart-heavy scenarios (with bidirectional in-flight TLC updates), channel reestablish/replay could become inconsistent, triggering Musig2VerifyError(BadSignature) and finally trigger channel force-close (fund is not affected).
  • The fix direction is to persist and validate replay context (CommitDiff) so replay is deterministic after restart, and to preserve strict replay ordering.
  • PR: fix(reestablish): stabilize commitment replay across node restarts #1111

In Pipeline

• Fiber type-system/CLI migration Add fiber cli #1144
  • fiber-types is being extracted as a standalone Rust crate for Fiber core domain types. This allows ecosystem developers to reuse protocol/channel/payment/invoice data structures without embedding the full node.
  • fiber-json-types (RPC-facing types, i.e. fiber-rpc-types) is being split as an independent crate for JSON-serializable RPC payloads, making SDK/tooling integration easier for external Rust projects.
  • fnn-cli is being introduced as a dedicated Fiber CLI with both one-shot and interactive usage, including info / peer / channel / invoice / payment / graph / cch / dev / watchtower / prof command groups.
  • A new payment RPC list_payments is added.
• External wallet signing for channel funding feat: add external wallet signing for channel funding #1083
  • New RPC methods:
    • open_channel_with_external_funding: negotiates with peer and returns an unsigned funding transaction for external signing.
    • submit_signed_funding_tx: submits the externally signed funding transaction and continues channel opening.
  • This introduces AwaitingExternalFunding state and reuses existing funding timeout handling, so users can keep funding keys in their own wallets while still using Fiber channel workflows.
• Fiber SDK + ecosystem demos
  • Fiber Pay: continued iteration on an AI-friendly CLI payment experience for Fiber users. (https://talk.nervos.org/t/fiber-pay-an-ai-friendly-cli-for-fiber-network/9974)
  • Fiber Audio Player: polishing a Fiber-based audio payment demo to validate user-facing payment interactions.
    • https://github.com/RetricSu/fiber-audio-player
    • https://fiber-audio-player.vercel.app/
  • Fiber SDK and Web5 demos: ongoing work to improve developer onboarding and to validate app integration patterns with Fiber.