Joe Kelly

Product Designer
Software Engineer
Writer @joekelly100 on
Author of
A Book Of The Way arrow
June 2022

Empower people to counteract misleading information and embrace uncertainty.

→ Decrease polarisation in society
→ Increase our capacity for productive disagreement
→ Recover a healthy information ecosystem


Fallible is a revolutionary new addition to the way you stay informed and answer crucial questions in today's complex world.

It's a social platform designed entirely around maintaining a probabilistic mindset and avoiding common causes of misjudgment.


This powerful way of thinking can become second nature thanks to intuitive UI and UX that's been made specifically to support it.

You almost can't help but think probabilistically if that's how everything is presented. And as you're browsing the web, you can call on the collective wisdom of the community to supercharge your bullshit detector and augment your ability to identify potential misintuitions.

If you bring all these elements together and build a network around it, you get Fallible: the ultimate tool to help you master the naturally error-prone ways of the human mind.

My Role
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Research, design, and build
Fallible is under construction. We will be looking to raise seed funding from the right investors soon. If that's you please say hello.
Co-founder &
Head of Product
June 2016 - 2020

Get rid of the old, expensive, fraud-ridden card system and introduce a new era of ‘Smart Payments’ with much lower fees for merchants and better payment experiences for customers.


Curl is an upgrade to the way we pay which doesn't use cards: it's a completely new payment network designed from scratch to serve people and businesses instead of banks and card companies.


Curl works by @usernames and by turning your phone into a smart remote control for your bank account(s). You make Smart Payments by telling your own bank account @who to send money to and how much.

It's much cheaper than cards, no sensitive information needs to be exchanged at any time, even for online checkouts, and all your loyalty and discounts (like buy 6 coffees get your 7th free) gets handled for you automatically.

In your regular places, e.g. coffeeshop or lunch spots, you can even turn on Hands Free so everything about your payment is taken care of in the background and you just receive a push notification when it's done.

My Role
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Product design

I'm responsible for the overall design of Curl as a product — how it works, what it looks and feels like, and ultimately the value it produces for the people and businesses using it.

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iOS + Android

I lead the design of 2x mobile apps to turn your phone into a smart remote control for your bank account(s).

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Web checkout

We made an e-commerce checkout flow with no forms, no logins, and no sensitive information exchange.

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We made a merchant app for taking Curl payments in shops. It shows the shopkeeper a live list of nearby customers and reminds them of names and what each person's regular order is.

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As a product guy, I get my hands dirty down to the wire. These interfaces matter — they can have major implications for the people using the product and those working on it.

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Nothing beats understanding. Good product management means making sure the whole team knows what we're trying to achieve with each feature and, more importantly, why.

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Complicated plans tend to create more problems than they solve. Good plans are simplified as much as possible and leave room for adaptation.

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‘You make what what you measure’. Good task definitions are as specific as possible about goals, risks, and outcomes. And Trello is a good thing.

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iOS app

Written exclusively in Swift, it has a redux architecture and makes extensive use of event sourcing and public-key crypto.

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Point-of-sale app
Javascript - HTML - Sass

A fullscreen web app for taking Curl payments in shops, designed to run on any mobile device. This ‘Sidecar’ device sits next to the shop's main point-of-sale like a card machine, but better.

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Web checkout
Javascript - HTML - Sass

An e-commerce plugin for paying with Curl from any website — no forms, no passwords, and no sensitive information exchanged.

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Javascript - HTML - Sass

The public website needed coding too. In olden times, when dial-up modems used to make cool noises, they'd've called me the webmaster.

Goodbye cards 🔗

Curl mission statement — I wrote a blog post which says why Curl is here and what problem we're solving.

Terms and conditions 🔗

Human-readable T&C's — it's good to cut through the legalese and (try to) add a bit of life and humour instead.

Privacy policy

A straightforward explanation of how your data is protected as a Curl user.

COVID-19: Two Threats, One Path, No Good Solutions
COVID-19 Risk Assessment May 2020

“The coronavirus (SARS-CoV-2) has invaded our way of life and forced us into a brutal double bind where we have to navigate two highly destructive threats simultaneously—one biological, one economic.”
Series: How To Kill Bitcoin
A deep dive into the game theory that (they say) secures Bitcoin, and a strategy to disrupt it—ruining the system’s incentives, operating mechanisms, and end-user value proposition to bring about its death.
Series: On Bitcoin’s Fee-Based Security Model
An analysis of Bitcoin’s proof-of-work security mechanism, how it works, and the hidden blow-up risks that it creates.
Older stuff...

I joined Typeform just after they closed Series A. I went to Barcelona to be part of the API & Integration team with the goal of getting typeforms more embedded in other people's applications.


I made a purpose-built 'beat battle' platform (i.e. weekly music sampling competitions, where 1 sample is chosen then music producers each 'flip' it into a full track), complete with profiles, voting system, etc.

We got a couple thousand users, including participation by a handful of notable artists from the LoFi scene (they're kind of a big deal... people know them), and even attracted battle sponsors and prizes.

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