Fiber Dev Log 2026-06-25

[chenyukang]

Updates

Fiber remained focused on release hardening for v0.9 throughout this cycle. We are grateful to the researchers for their contribution to the safety of Fiber Network. In response to the increasing number of security reports from AI tools, our bugbounty standards have also been adjusted accordingly.

We published v0.9.0-rc4 on June 22, 2026, after another round of security-report follow-up, channel lifecycle fixes, watchtower hardening, CCH work, and fiber-js/npm release-readiness improvements.

As of June 24, the v0.9 milestone remains open, with the final v0.9.0 release underway.

Most merged work focused on improving reliability, safety, and more stability rather than adding large new features. Key areas include TLC expiry/accounting correctness, commitment-point and gossip validation, external-funding restart behavior, watchtower settlement and cleanup paths, and CI / release packaging stability.

Features

v0.9.0-rc4 Pre-Release

Published Fiber v0.9.0-rc4 as the latest v0.9 release candidate.

• v0.9.0-rc4 release
• v0.9.0-rc3 to v0.9.0-rc4 full changelog
• chore: bump version to 0.9.0-rc4

fiber-js and npm Release Readiness

Updated fiber-js for newer TypeScript support and made npm CI/release inputs more reproducible.

• fiber-js: adapt newer TypeScript version
• fix: commit package-lock.json for npm ci compatibility

Improvements & Fixes

Security and Protocol Hardening

Continued addressing findings from security reviews, across gossip, RPC scope, custom records, peer-supplied points, and malformed input paths.

• harden gossip result handling
• Require dev scope for dev RPC
• Validate custom records size
• fix: validate peer tlc_basepoint and per_commitment_point before accept
• fix: validate next_per_commitment_point in RevokeAndAck against tlc_basepoint
• fix: remove panic paths from UDT regex and CKB RPC byte responses

Channel, Funding, and TLC Lifecycle

Tightened restart, reconnect, external-funding, cleanup, and retry behavior around channel state transitions.

• fix: prevent funding abort when tx is committed on chain after restart
• fix: report permanent SendTx failures via tracer to restore abort_funding
• fix: gate external funding TxUpdate sync on is_acceptor or signed_submitted
• fix: delete stale channel-open records on peer disconnect
• fix TLC in-flight limits after failed cleanup
• fix: record incorrect TLC expiry on reporting channel
• fix: coalesce ChannelReady retry scans

Watchtower and Reestablishment Stability

Hardened watchtower settlement, cleanup, and reestablish paths, including several e2e and regression-stability fixes.

• fix: watchtower multi-pass settlement tx scan for child-before-parent indexer ordering
• Stabilize watchtower multiple payments e2e
• fix: prevent overflow panic on commitment_number=0 in watchtower settlement
• fix: restrict watchtower channel removal to closed channels
• fix: add reestablish timeout to prevent peer from stalling TLC safety handling indefinitely
• fix: debounce payment retry scans on reestablish to prevent resource exhaustion

CCH and Routing Stabilization

Landed the CCH outgoing payment fee-budget binding and several trampoline/TLC expiry fixes.

• fix: bind CCH fee budget to outgoing payments
• test: stabilize max trampoline hops routing
• Add migration for TrampolineContext max_outgoing_tlc_expiry
• Stabilize trampoline rand expiry

In Pipeline

v0.9 Finalization

Final v0.9.0 is still pending. The latest confirmed pre-release is v0.9.0-rc4, and the v0.9 milestone remains open.

CCH Follow-Ups

CCH pending-expiry reconciliation has been approved with green checks, while the broader CCH multi-asset swap remains in review.

Active PRs:

• Fix CCH pending expiry reconciliation
• feat!(cch): CCH multi-asset swap

Force-Close TLC Settlement

Force-closed channel TLC settlement remains in review, with CI and e2e checks passing.

Active PR:

• feat: handle on-chain TLC settlement for force-closed channels

Remaining Hardening and Operator Work

Gossip rate-limit bounds and selected operator/RPC improvements remain in progress or waiting for final review.

Active PRs:

• fix gossip rate limit bounds
• Add fee stats RPC
• feat: add backup and restore for storage backends