CKB Dev Log 2026-08-19

[chenyukang]

Updates

This cycle (July 22 – August 18, 2026) focused on the CKB v0.209.0 release, network and light-client hardening, and the next phase of tx-pool architecture work.

Key milestones include:

• CKB v0.209.0 shipped with fixes for memory growth, tx-pool ancestor eviction, jemalloc profiling, and Tor connectivity.
• Tentacle 0.7.7 resolved a QUIC compatibility fix; broader QUIC integration remains under review.
• Developer Tooling saw ckb-cli gained parity with the node's richer live-cell response, improved contract templates and guides, and a ckb-tui integration entering review.
• CKB-VM tightened its lint baseline and published two additional technical deep-dives.
• DAO Treasury & Voting design advanced a batch tally settlement solution. The work remains in design and PoC stages.

Releases & Features

CKB v0.209.0 (July 29, 2026)

This regular minor release improves Tor connection handling, prevents unbounded logger and relay-queue memory growth, fixes tx-pool ancestor eviction and jemalloc profiling, and carries forward miner-notify authentication and release-workflow hardening.

• Prevent unbounded logger and relay-queue memory growth
• Fix stale-parent handling during tx-pool ancestor eviction
• Correct the jemalloc profiling-dump FFI
• Replace torut with a manual Tor implementation

Tentacle 0.7.7 (August 17, 2026)

This release explicitly selects the AWS-LC crypto provider for QUIC, preventing rustls initialization failures when downstream workspaces enable both AWS-LC and ring.

• Select the rustls AWS-LC crypto provider for QUIC

Improvements & Fixes

Core reliability & packaging

CKB stabilized transaction-pool eviction, profiling, packaging, and Tor liveness paths. The crate-release sequence was also corrected so ckb-verification-contextual can be packaged against the updated verification cache API.

• Detect Tor control-connection loss through TcpStream close
• Simplify the ancestor eviction loop
• Bump ckb-verification-contextual to unblock package and publish

Light-client verification hardening

The light client now validates V1 proof-response field lengths, requires proof before advancing subscribed tips, and verifies downloaded block bodies against the commitments in their proved headers before indexing.

• Validate V1 message field lengths and handle missing checkpoints
• Require proof before advancing subscribed tips
• Validate downloaded block data before indexing

Networking reliability & security

Tentacle added connection-limit boundary checks, bounded high-priority substream buffering, discovery listen-port validation, and cleanup of protocol notification timers.

These changes reduce over-capacity acceptance, unbounded buffering, invalid peer-address storage, and stale timer activity.

• Fix the maximum connection-limit boundary
• Apply backpressure to high-priority substream buffers
• Validate peer-supplied discovery listen ports
• Clear session notification timers on protocol close

Tooling and developer experience

ckb-cli now exposes the block_hash returned by the node's richer get_live_cell RPC response, keeping CLI output aligned with CKB v0.208.0 and later. Dependency updates are also grouped to keep the lockstep CKB crate set reviewable.

• Surface block_hash in ckb-cli get_live_cell
• Group Dependabot dependency updates

Contract development documentation and templates improved for both C and Rust workflows. The C standard library gained a practical build-and-test guide, and generated script projects can once again run make from a contract subdirectory.

• Add a developer guide for building and testing CKB C contracts
• Fix make execution from generated contract subdirectories

CKB-VM maintenance and knowledge sharing

CKB-VM removed obsolete Clippy configuration, enabled additional lint checks, and aligned the RFC hardfork description with the removal of the A extension.

• Enable the unnecessary_cast Clippy check
• Remove obsolete Clippy configuration
• Enable the collapsible_if Clippy check
• Remove the A extension from the CKB-VM 2023 hardfork description

Two new technical articles explain CKB-VM cycle accounting and the instruction-decoder/cache design.

• Deep Dive Into CKB-VM Cycles
• Deep Dive Into CKB-VM Instruction Decoder and Instruction Cache

More in this series: https://talk.nervos.org/t/deep-dive-into-ckb-vm-instruction-decoder-and-instruction-cache/10592#p-25562-series-of-articles-9

DAO treasury and voting research

The DAO treasury work advanced on both the treasury-funding mechanism and the voting/settlement path.

Voting design work is exploring historical DAO voting-power proofs and scalable on-chain settlement. The current directions combine proofs that specific DAO cells were live at a selected historical snapshot with a consensus-defined aggregate for total eligible voting capacity, plus batch tally sessions, omission challenges, and immutable passing-policy configuration. Benchmarking and checkpoint work continue to refine throughput and proof size.

These mechanisms would require a future hardfork and remain active design and PoC work rather than a confirmed protocol change. Production wallet/signing flows, deployment parameters, adversarial benchmarks, and final consensus rules are still under discussion.

• Add a checkpointed updating phase
• https://github.com/chenyukang/ckb-treasury-lab/tree/dao-treasury-contracts

In Pipeline

Transaction-pool architecture

• The earlier multi-stage pipeline prototype was closed without merge on August 7.
• Next Iteration: Work has shifted to an invariant-driven, single-authority validate → plan → apply → effects model, with model-based correctness, mutation, performance, and cold-replay gates under development before a new public integration path is proposed.
  • Previous tx-pool pipeline prototype

CKB QUIC integration

• Initial CKB integration remains under review after Tentacle 0.7.7 resolved the downstream rustls provider conflict.
• The PR (network: initial integration for quic #5295) enables QUIC for non-WASM builds and adds QUIC address handling, discovery, Identify validation, outbound selection, tests, and a dual TCP/QUIC configuration example.

CKB and light-client hardening

CKB open reviews include: bounded Tor control-line handling, proxy-credential redaction, rich-indexer rollback behavior, and graceful recovery from malformed local versionbits cache entries.

• Bound and drain Tor control lines
• Redact proxy credentials in startup logs
• Skip empty spent-cell resets during rich-indexer rollback
• Avoid panic on malformed versionbits cache entries

Light-client follow-ups remain in review for validating headers before last-state proof processing and retrying matched-block retrieval through a different peer when an MMR lookup cannot find the expected block hash.

• Validate verifiable headers before processing last-state proof
• Retry matched-block retrieval through another peer

Developer tooling & reproducible releases

• Terminal UI: ckb-tui integration remains under review as a new ckb-cli tui subcommand: Integrate ckb-tui into ckb-cli
• AI Guidance: A companion documentation PR is also open to provide AI agents with project-specific guidance for Rust on-chain scripts: Add an AI-agent guide for CKB Rust script templates
• Guix Releases: The Guix-based reproducible release flow remains open, covering pinned build inputs and multi-platform release builds for Linux, macOS, and Windows: Add the Guix reproducible release flow

CKB-VM compatibility follow-up

The LUI+JALR macro-op fusion overflow guard remains under review for the VERSION3 compatibility boundary: Guard LUI+JALR macro-op fusion against overflowing immediates