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Building a Bitcoin ATM is easy, but…

A new section about Bitcoin ATM business models
has been added. Jump to “UPDATE – July 2019

The good news is that building a Bitcoin ATM is easy and less expensive than you might expect. But, offering or operating them engulfs the assembler in a regulatory minefield! It might just be worth sticking to selling bitcoin on PayPal (visit this website for more information on that). You might also wish to rethink your business model—especially user-demand scenarios. See our 2019 update at the bottom of this article.

A photo of various Bitcoin ATMs appears at the bottom of this article. My employer, Cryptocurrency Standards Association, shared start-up space at a New York incubator with the maker of a small, wall mounted ATM, like the models shown at top left.

What is Inside a Cryptocurrency ATM?

You could cobble together a Bitcoin ATM with just a cheap Android tablet, a camera, an internet connection, and [optional]: a secure cash drawer with a mechanism to count and dispense currency).* A receipt printer that can also generate a QR code is a nice touch, but you don’t really need one. You can use your screen for the coin transfer and email for a receipt.

Of course your programming and user interface makes all the difference in the world. And your ATM must interface with an exchange—yours or a 3rd party exchange.

If your plan is to sell Bitcoin and not exchange it for cash, then you don’t need a currency dispensing component at all. You only need a credit card swipe-reader and an RFI tap reader. Some models are smaller than a cookie and sell for under $30. They can be attractively embedded into your machine. In fact, some bank card processors offer them without cost.

I Have Built a Prototype. Now What?

Desktop ATM. No cash dispensed

What happens to your Bitcoin if you die or forget passwords?

Legacy Method of Inheriting Assets

Many Bitcoin owners choose to use a custodial account, in which the private keys to a wallet are generated and controlled by their exchange—or even a bank or stock broker. In this case, funds are passed to heirs in the usual way. It works like this…

An executor, probate attorney, or someone with a legal claim contacts the organization that controls the assets. They present a death certificate, medical proxy or power-of-attorney. Just as with your bank account or stocks and bonds, you have the option of listing next of kin and the proportion of your assets that should be distributed to each. These custodial services routinely ask you to list individuals younger than you and alternate heirs, along with their street addresses, in the event that someone you list has died before you.

Of course, Bitcoin purists and Libertarians point out that the legacy method contradicts the whole point of owning a cryptocurrency. Fair enough.

Multisig to the Rescue

Using multisig would be far easier, if wallet vendors would conform to standards for compatibility and embed technology into hardware and software products. Unfortunately, they have been slow to do so, and there are not yet widely recognized standards to assure users that an implementation is both effective and secure. But, there is some good news: It’s fairly easy to process your ordinary account passwords and even the security questions with a roll-your-own multisig process. I’ve done it using PGP and also using Veracrypt—two widely recognized, open source encryption platforms.

This short article is not intended as an implementation tutorial, but if the wallet vendors don’t jump up to home plate, I may release a commercial tool for users to more easily add multisig to their wallets. It really is safe, simple and effective. (If readers wish to partner with me on this? I estimate that it will take $260,000 and about six months).

What is Multisig and How Does it Protect your Wealth?

Multisig allows anyone with credentials to an account, wallet or even a locked safe to create their own set of rules concerning which combinations of friends and relatives can access their assets without the original owner. The owner sets conditions concerning who, when, how much and which accounts can be accessed — and the heirs simply offer passwords or proof of identity. If implemented properly, it doesn’t matter if some of the heirs have forgotten passwords or died before the original owner.

This can be illustrated in an example. I am intentionally describing a complex scenario, so that you consider a full-blown implementation. Although the ‘rules’ listed below appear to be complex, the process for creating the associated passwords is trivial.

The last 2 rules listed below do not use Multisig technology, but rather Smart Contracts. It enhances an owner’s ability to dictate terms. Here, then, is the scenario…

I want heirs to have access to my assets
at banks, brokers, exchanges or other ac–
counts–but only under certain conditions:

  • If any 4 of 11 trusted family and friends come together and combine their passwords (or an alternate proof-of-identity), they may access my wealth and transfer it to other accounts
    • But, if one is my husband, Fred, or my daughter, Sue, then only two trusted individuals are needed
    • —But not Fred and Sue together (At least one must be an outsider)
  • If any account has less than $2500, then it goes to my favorite charity, rather than the individuals I have listed
  • None of my accounts can be unlocked by my heirs, until I have not accessed them with my own password for 3 months. Prior to that, the Multisig will fail to gain access.

Again, the decedent’s wishes are complex, but executing and enforcing these rules is trivial. In my presentations, I describe the method on two simple PowerPoint slides. Even that short description is sufficient to show anyone who has used common cryptography apps to weave their own multisig add-on.

Of course, each individual will need to locate their own secret password, but a biometric or other conforming proof-of-identity can be substituted. Even if several survivors cannot recall their credentials, the multisig method allows other combinations of individuals to access the assets across all accounts.

This article may leave you wondering about the legal process—and this is where I agree with the Libertarian viewpoint: Sure! The courts have a process and heirs should document their access and decisions for tax purposes and to assure each other of fair play. But a key benefit of cryptocurrency and the disintermediation offered by the blockchain is the personal empowerment of access with impunity and without waiting for any legal process.

Let the courts to what they do, while you honor the wishes of your dearly departed.

If this article generates sufficient interest, I may prepare a short tutorial on how to split off your own Multisig passwords, regardless of which wallet or hosted services you use. It will work with any vendor, app or gadget —or— Perhaps, I will refine my homespun solution and offer it as an add-on app that can be used with any wallet, bank account or exchange. Simple, ubiquitous and effective multisig should have been available to even traditional banking customers years ago!


Philip Raymond co-chairs CRYPSA, hosts the New York Bitcoin Event and presents at
Crypto Conferences around the world. Book a presentation or consulting engagement.

Have there been successful Transaction Malleability attacks?

First, let’s get some basics out of the way…

What is Transaction Malleability?

Here are 2 explanations of transaction malleability: [Coindesk] [TechTalk]

In a nutshell, Transaction Malleability is a weakness in the original Bitcoin implementation that enables a bad actor to change the unique ID of a bitcoin transaction before it is confirmed on the Blockchain. Such a change makes it possible for someone to pretend that a transaction didn’t happen, if all necessary conditions are in place.

As the Coindesk article points out, a successful attack requires certain conditions that make a successful attack difficult or even unlikely. Many analysts referred to it as a bug that should eventually be fixed, rather than an urgent issue.

Was This Flaw Addressed

Transaction malleability was addressed (for Bitcoin) with the introduction of Segregated Witness (SegWit) in August 2017. 1, 2

But Was There a Successful Attack?
Attack? Yes. Successful? It’s doubtful…

In March 2017, five months before SegWit was implemented, a mining pool that administers 2% of worldwide activity launched a malleability attack. No one lost money – and some individuals believe that they did this to emphasize urgency and hasten the adoption of SegWit.

What About Lightning Network?

The Lightning Network is a ‘Level 2’ network overlay, currently being adopted by miners (depending on the service or exchange, it is being incrementally activated in the first months of 2018). To function properly, it requires that transaction malleability be solved. But, in the event that a miner is not SegWit compliant, it can resolve the malleability problem in other ways.

1 SegWit should not be confused with SegWit2x, an upgrade process that was cancelled a few months later in November. 2017

2 In the TechTalk article linked above, the author concludes:

“Transaction Malleability is fixed with Segregated Witness by no longer taking into account signatures when calculating the transaction’s fingerprint. Fixing Transaction Malleability means that the Lightning Network can work smoothly.”


Philip Raymond co-chairs CRYPSA, hosts the New York Bitcoin Event and presents at
Crypto Conferences around the world. Book a presentation or consulting engagement.

Waking up From the Dream of Longevity

In the course of the last century, science fiction has been a harbinger of things to come. From the automatic sliding doors of Star Trek to visual communication, cyberspace, and even the moon landing, many of our present technological achievements were dreamed up in the futuristic visions of science fiction authors of the 1960s and 70s. Indeed, the fantastical world of science fiction, while not intended to be prophetic, has ended up acting as a blueprint for our modern world.

We have learned from science fiction not only the possibilities of technology, however, but also its irreconcilable dangers. Readers of the genre will recognize the many stories warning us of the hazards of space travel, mind enhancement, and artificial intelligence. These fictional accounts cautioned that if we were not careful, our freedom to transform the world around us would transmogrify into a self-enforced slavery.

Nonetheless, while many of us remembered that these were just stories, intended as speculations about a possible future—in other words, they were fiction before science—through them, we became used to the idea that any advanced technology was inherently dangerous and its use always suspect. Moreover, it became a commonplace idea that technologies whose aim was to change or transform the human being—whether genetic, biological or reconstructive—would lead to a future worthy of Mary Shelley’s Frankenstein.

The Moon Is Getting A 4G Network

For all those people wandering around our great Australian cities and spewing they can’t watch a streaming video over 4G because of network access and congestion — we’ve found a place where you can get access to a brand new 4G network that isn’t being hammered. The downside — you’ll need to travel about 384,000km to get there. Nokia and Vodafone are teaming up to put 4G on the moon.

German company PTScientists is planning the first privately-funded Moon landing in 2019, using a SpaceX Falcon 9 rocket from Cape Canaveral. Their plan is is to look at an old roving vehicle left behind back in 1972, when the last Apollo mission left the lunar surface. And, to do that, the new vehicles they’re sending up small, 1kg, base stations to transmit HD images from the moon’s surface back to earth for the first time. Audi is building the vehicles that will be used on the lunar surface.

Nokia said “The 4G network will enable the Audi lunar quattro rovers to communicate and transfer scientific data and HD video while they carefully approach and study NASA’s Apollo 17 lunar roving vehicle that was used by the last astronauts to walk on the Moon”.

Would an ethical government surrender control of monetary policy?

Godfrey Bloom is a member of the British Parliament. His in-your-face style of educating and shocking his peers has made him a controversial politician. He has occasionally been escorted out of the assembled parliament because of his rowdy rhetoric.

Consider the video below. Bloom offers a critical, but simple and clear explanation of the Fractional Reserve banking system used in the US and Europe. This gets to the heart of the matter! [continue below video]…

Conclusion (mine, and not Mr. Bloom’s): It is in the interest of governments to use a form of money that they cannot manipulate, print, spend, hide or lend without first earning, taxing or legitimately borrowing — and then balancing the books, openly.

Bitcoin is such a currency. Any country that adopts an open source, permissionless, and completely transparent monetary instrument will demonstrate to citizens and taxpayers that they respect their constituents and that they commit to balance their books like any state, corporation, NGO or household.

Would an ethical government surrender control of its own monetary policy? H*ll, yes! This is how a government avoids rampant inflation and the burden of non-consensual debt to future generations. It is also how a government makes taxation, redistribution and spending transparent and accountable. It is how a government restores trust.

We have been raised with centuries of dogma that teach us to accept inflation, and a constantly escalating public debt. Sometimes, the path forward is not immediately obvious. But history doesn’t lie. When trusted nations with large economies manipulate interest rates, borrow without a lender, or inflate a nation out of a crisis (what the US calls “quantitative easing”), the long term effect is certain to be no different than Argentina, Zimbabwe, Venezuela or Germany between the wars. It is a recipe for disaster. It places every citizen and their future children into debt-bondage.

Moving away from the Gold Standard in the 1970s was a risky maneuver. The risk was not abandoning a precious metal with intrinsic value—but rather it placed the full faith and credit of our economy in the hands of transient politicians, rather than in a capped commodity with certain and immutable properties.

Bitcoin is the new gold. It is capped, transparent, open-source, vetted and without a mechanism for quick or covert manipulation (the US calls this “raising the debt ceiling” and they do it every few months!). We may not move to an economy based on Bitcoin today or tomorrow, but that day is coming. Thankfully, it’s coming!


Philip Raymond co-chairs CRYPSA, publishes A Wild Duck and hosts the New York Bitcoin Event. He was speaker at Cryptocurrency Conferences in Dubai, South Africa and India. Click Here to inquire about a presentation.