CoinJoin doesn’t guarantee privacy—it just buys you a chance at privacy. One slip post-mix, and intersection attacks can trace you all the way back. Leaks compound fast, and even “perfect” mixes can collapse under real-world pressure. All this and more in The Scroll #4, the longest document or newsletter we have ever published:

The Scroll #4: Intersection Attacks on CoinJoin Anonymity

This is not only our longest edition of The Scroll yet, it might be the longest document we’ve ever published. But, you know what? This is for go...

Mining centralization is one of the biggest risks facing bitcoin. You can help solve it. Spiral is offering a unique grant opportunity for a Senior Engineer to significantly advance Stratum V2. We’re looking for a highly skilled individual with a proven track record in Rust development, specifically within mining infrastructure and distributed systems. The ideal person will excel at building scalable, application-layer APIs, servers, and proxies for real-world deployments. You’ll be at the forefront of creating open-source building blocks for the mining ecosystem.

In this third Plushie Confidential installment, we cover the huge response that Bitty and Itty Bitty got in Japan, as well as our plans to triple down on the Japanese plushie market. Hate reading? Push play to have a dapper Englishman read it to you.

Plushie Confidential #3: The Tokyo Connection

Sometimes Your Market Finds You.

In this edition of What’s Matt Mad At Now, he covers MEVil, his talk at bitcoin++ tomorrow, Core standardness rules, and all of it flavored by his incandescent, seething, volcanic rage.

The MEVil of Relay Policy

Matt’s back at it, and this time, he’s madder than ever.

Please welcome our first Texan, @benthecarman, to Spiral. After one year probably doing JPEG work at Taproot Wizards, Ben will tackle LDK Server and a new SDK that simplifies how we onboard self-custodial bitcoin users, two things that his Mutiny wallet work lend themselves to.

Opinions vary on how best to get strangers into bitcoin.

Spiral wizard Yuval Kogman gets to put ”wizard” as his occupation on tax forms, legal documents, and lease applications for a reason. “The Scroll #3: A Brief History of Wallet Clustering“

The Scroll #3: A Brief History of Wallet Clustering

Our previous post in this series introduced the idea behind wallet or address clustering, the trivial case of address reuse, and the merging of clu...

April’s Nerd of the Month is @the_charlatan_. This one’s so nerdy that it took four of us to make it understandable even to other nerds.

Nerd of the Month: Bitcoinkernel Library

April’s Nerd of the Month is @the_charlatan_, a Spiral grantee whose work on Bitcoin Core’s build system, validation engine, and long-term arch...

Just because our quarterly progress report is now multiple newsletters doesn’t mean we still can’t have a quarterly progress report. It just means that it’s much shorter and mostly bullet points because none of us have attention spans anymore:

2025 Q1 Spiral Progress Report

What you need to know about how little we know.

From the same bitcoin co-working and events space that brought you Presidio Bitcoin Jam comes a no-holds-barred adrenaline-fueled thrill ride called 21 in 21, where our own Haley Berkoe asks people like this dude you’ve never heard of 21 questions about bitcoin in 21 minutes:

This post was originally released a couple of days ago on

Lightning Dev Kit Documentation

A complete Lightning implementation packaged as an SDK

LDK is a flexible lightning implementation with supporting batteries (or modules).

by some devs who forgot that Spiral now has a newsletter that covers, among other things, LDK-related stuff like VSS. As recompense, they have all been assigned to eat a bowl of spiders.

LDK: Announcing Versioned Storage Service (VSS)

A solution for live online sync and lightning state backup for non-custodial wallets.

The Nostr community could be the only community that understands our latest newsletter. Twitter seems to be struggling:

The Scroll #2: Wallet Clustering Basics

In this new recurring newsletter, The Scroll, we’ll be highlighting the highly technical concepts happening within bitcoin.

This is quickly becoming my all-time favorite Spiral writing project. And we have had SO MANY of those over the years:

Plushie Confidential #2: Rooting for the Little Guy

This post focuses on how Itty Bitty came to be and what your marketing team can learn from our wins, losses, and outright mistakes.

If your bitcoin investment strategy can’t fit in a fortune cookie, it’s too complicated.

In our latest blog post, Spiral’s Bitcoin Wizards are highlighting potential upgrades to the Bitcoin Scripting system that will enable improved scaling across the network, starting with topics like the economic limits of self-custody.

The Scroll: UTXO Sharing

In this new recurring newsletter, The Scroll, we’ll be highlighting the highly technical work being done by our Bitcoin Wizards team, who, as it ...

How we got into the bitcoin plushie business, part 1:

Plushie Confidential #1: Big Start, Small Finish

Puppets weren’t enough.

Drawn between doing another plushie that is either this herecomesbitcoin.org cat or this Warhammer-inspired battle mech. These are the kind of decisions you get to make working within the bitcoin space and practically nowhere else.

Last day to save big on small:

Bitkey | Plushie X Bitkey | Free Itty Bitty Plushie

A bitcoin wallet to own your private keys. Bitkey includes an app, hardware wallet, and recovery tools in case you lose your phone, or hardware, or...

Our free-to-use library of bitcoin assets has a new look:

Here Comes Bitcoin

Here Comes Bitcoin is the central resource for all things Bitcoin (puppet, not currency), including license-free creative assets that you can use t...