kubo/docs/changelogs/v0.40.md

Kubo changelog v0.40

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• v0.40.0

v0.40.0

• Overview
• 🔦 Highlights
  • 🧹 Automatic cleanup of interrupted imports
  • Routing V1 HTTP API now exposed by default
  • Track total size when adding pins
  • Improved IPNS over PubSub validation
  • New ipfs diag datastore commands
  • 🚇 Improved ipfs p2p tunnels with foreground mode
  • Improved ipfs dag stat output
  • Skip bad keys when listing
  • Accelerated DHT Client and Provide Sweep now work together
  • 🔧 Recovery from corrupted MFS root
  • 📦️ Dependency updates
• 📝 Changelog
• 👨‍👩‍👧‍👦 Contributors

Overview

🔦 Highlights

🧹 Automatic cleanup of interrupted imports

If you cancel ipfs add or ipfs dag import mid-operation, Kubo now automatically cleans up incomplete data on the next daemon start. Previously, interrupted imports would leave orphan blocks in your repository that were difficult to identify and remove without pins and running explicit garbage collection.

Batch operations also use less memory now. Block data is written to disk immediately rather than held in RAM until the batch commits.

Under the hood, the block storage layer (flatfs) was rewritten to use atomic batch operations via a temporary staging directory. See go-ds-flatfs#142 for details.

Routing V1 HTTP API now exposed by default

The Routing V1 HTTP API is now exposed by default at http://127.0.0.1:8080/routing/v1. This allows light clients in browsers to use Kubo Gateway as a delegated routing backend instead of running a full DHT client. Support for IPIP-476: Delegated Routing DHT Closest Peers API is included. Can be disabled via Gateway.ExposeRoutingAPI.

Track total size when adding pins

Adds total size progress tracking of pinned nodes during ipfs pin add --progress. The output now shows the total size of the pinned dag.

Example output:

Fetched/Processed 336 nodes (83 MB)

Improved IPNS over PubSub validation

IPNS over PubSub implementation in Kubo is now more reliable. Duplicate messages are rejected even in large networks where messages may cycle back after the in-memory cache expires.

Kubo now persists the maximum seen sequence number per peer to the datastore (go-libp2p-pubsub#BasicSeqnoValidator), providing stronger duplicate detection that survives node restarts. This addresses message flooding issues reported in #9665.

Kubo's pubsub is optimized for IPNS use case. For custom pubsub applications requiring different validation logic, use go-libp2p-pubsub directly in a dedicated binary.

New ipfs diag datastore commands

New experimental commands for low-level datastore inspection:

• ipfs diag datastore get <key> - Read raw value at a datastore key (use --hex for hex dump)
• ipfs diag datastore count <prefix> - Count entries matching a datastore prefix

These commands require the daemon to be stopped and are useful for debugging and testing. For example, inspecting pubsub seqno validator state:

$ ipfs diag datastore count /pubsub/seqno/
2
$ ipfs diag datastore get --hex /pubsub/seqno/12D3KooW...
Key: /pubsub/seqno/12D3KooW...
Hex Dump:
00000000  18 81 81 c8 91 c0 ea f6                           |........|

🚇 Improved ipfs p2p tunnels with foreground mode

P2P tunnels can now run like SSH port forwarding: start a tunnel, use it, and it cleans up automatically when you're done.

The new --foreground (-f) flag for ipfs p2p listen and ipfs p2p forward keeps the command running until interrupted. When you Ctrl+C, send SIGTERM, or stop the service, the tunnel is removed automatically:

$ ipfs p2p listen /x/ssh /ip4/127.0.0.1/tcp/22 --foreground
Listening on /x/ssh, forwarding to /ip4/127.0.0.1/tcp/22, waiting for interrupt...
^C
Received interrupt, removing listener for /x/ssh

Without --foreground, commands return immediately and tunnels persist until explicitly closed (existing behavior).

See docs/p2p-tunnels.md for usage examples.

Improved ipfs dag stat output

The ipfs dag stat command has been improved for better terminal UX:

• Progress output now uses a single line with carriage return, avoiding terminal flooding
• Progress is auto-detected: shown only in interactive terminals by default
• Human-readable sizes are now displayed alongside raw byte counts

Example progress (interactive terminal):

Fetched/Processed 84 blocks, 2097152 bytes (2.1 MB)

Example summary output:

Summary
Total Size: 2097152 (2.1 MB)
Unique Blocks: 42
Shared Size: 1048576 (1.0 MB)
Ratio: 1.500000

Use --progress=true to force progress even when piped, or --progress=false to disable it.

Skip bad keys when listing

Change the ipfs key list behavior to log an error and continue listing keys when a key cannot be read from the keystore or decoded.

Accelerated DHT Client and Provide Sweep now work together

Previously, provide operations could start before the Accelerated DHT Client discovered enough peers, causing sweep mode to lose its efficiency benefits. Now, providing waits for the initial network crawl (about 10 minutes). Your content will be properly distributed across DHT regions after initial DHT map is created. Check ipfs provide stat to see when providing begins.

🔧 Recovery from corrupted MFS root

If your daemon fails to start because the MFS root is not a directory (due to misconfiguration, operational error, or disk corruption), you can now recover without deleting and recreating your repository in a new IPFS_PATH.

The new ipfs files chroot command lets you reset the MFS (Mutable File System) root or restore it to a known valid CID:

# Reset MFS to an empty directory
$ ipfs files chroot --confirm

# Or restore from a previously saved directory CID
$ ipfs files chroot --confirm QmYourBackupCID

See ipfs files chroot --help for details.

📦️ Dependency updates

• update go-libp2p to v0.46.0
  • Reduced WebRTC log noise by using debug level for pion errors (go-libp2p#3426).
  • Fixed mDNS discovery on Windows and macOS by filtering addresses to reduce packet size (go-libp2p#3434).
• update quic-go to v0.57.1 (incl. v0.56.0 + v0.57.0)
• update p2p-forge to v0.7.0
• update go-ds-pebble to v0.5.8
  • updates github.com/cockroachdb/pebble to v2.1.3 to enable Go 1.26 support
• update go-libp2p-pubsub to v0.15.0

📝 Changelog

👨‍👩‍👧‍👦 Contributors