Hi Insiders. This is Tuma, open-source reporter from the Insider Edition.
In this week’s update we feature the latest release, v3.1.0, of the bindings library for BDK, exposing the latest development to several programming languages.
We also cover the publication of BIP332, defining a new, opt-in P2P message, a a new BIP that has been assigned a number, BIP394, which defines a new output script descriptor, called rawtr() .
We finally discuss some other news from the Bitcoin developer ecosystem. In particular, we talk about a bug in the legacy gateway module in Fedimint, a blog post from Second on how to board an Ark using Payjoin, and a research from BlueWallet CTO on the security of non-custodial wallets on the App Store.
Highlights from the Bitcoin developer ecosystem
I spent 10+ hours in open-source developer calls in the Bitcoin ecosystem last week. Here is what caught my eye:
The BDK team released the latest version of their bindings, v3.1.0, bringing the whole library to several programming languages
During their weekly call, on Tuesday 8th, BDK contributors discussed the release of
bdk-ffiv3.1.0, the library that allows to expose the Rust codebase to several other programming languages, such as Dart, Swift, Kotlin, Python, and react-native.This release upgrades UniFFI — the bindings generator — to v0.31.2 and brings the bindings up-to-date with the latest release of the BDK Wallet libraries, exposing several new methods, such as those to choose the coin selection algorithm, wallet signers, APIs to load wallet parameters, and more.
bdk-dart— the library exposing BDK to Dart — has been upgraded to use the latestsbdk-ffilibrary, and a new release candidate, v1.0.0-rc.4 has been published. This update brings the Dart bindings closer to a first stable release.
A BIPs Update
In the last days there was some movement in the BIP repository. Specifically, one new BIP has been published and one has been assigned a number by BIP maintainer Murchandamus.
Published BIPs
A list of recently published BIPs
BIP332: Stale Tip Relay
Authors: Anthony Towns, w0xlt, Ram
Published On: Sep 9th, 2026
Layer: Peer Services
BIP 332 defines a new, opt-in P2P message called staletip whose goal is to announce recent stale chain tips to peers. The message contains the block height at which a stale branch diverges (the fork point), a vector containing the block headers belonging to the stale branch, and a flag signaling willingness to serve that block data. This may be useful for monitoring the network health, since increases in the stale block rate may expose validation or relay bottlenecks, network partitions, or selfish mining behavior.
Numbered BIPs
A list of BIPs that recently got assigned a number
BIP394: rawtr() Output Script Descriptors
Authors: jeanpablojp
Assigned On: Sep 9th, 2026
Layer: Applications
PR2251 introduces BIP394, which defines a new output script descriptor, called rawtr() . The descriptor — that has been available in Bitcoin Core since v24.0 but was never specified in a BIP — can be used to express a P2TR output directly by its output key. The key is used as the taproot output key without applying the BIP341 tweak. This is useful, for example, when the internal structure isn’t known, or the script tree hasn’t been revealed by the owner.
Other News from the Bitcoin World
Fedimint Bug: The Fedimint team announced that they had found a bug in the legacy gateway module, the one responsible for integrating the federated ecash ecosystem with the Lightning Network.
The team released v0.12.1 to fix the issue and contacted all the reachable gateway operators to invite them to update their modules as soon as possible.
The issue only affects legacy gateway modules, those running the so-called LNv1, while those that had previously upgraded to LNv2 or those running an LDK backend can run safely. The team also point out that users’ funds, federations, and ecash are not affected by the bug.
Boarding an Ark with Payjoin: Second, the company behind Bark, posted a thread explaining how to board and Ark using Payjoin, a feature that has been available for some time now. The same flow is also available to enter a Cashu mint. Second also provided a full write-up on the topic.
App Store Research: BlueWallet CTO @overtorment pubished a report on the security of non-custodial wallets on the App Store.
The research focused on finding traces of weak entropy and private key exfiltration by decompiling and analyzing code from different wallets.
@overtorment was able to decompile 494 wallets, 45 of which raised red flags. He identified 23 apps with critical vulnerabilites and 22 with high-severity one. The complete list can be found at the end of the report.
Bitcoin++ Insider Edition — News Hour: On Friday, the Insider team held its first News Hour, a livestream where we discussed the most important news of the week, interesting articles, and the latest insides from the developer ecosystem. This will become a weekly appointment, so don’t forget to tune in on Friday @ 5p UTC!
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