Publications

Have you ever tried using ssh on a train? Or closed your laptop and found that all of your remote session are now frozen? Or using it via a crowded antenna tower? In all theses cases, ssh fails to work as expected. This is due to the fact that common…

One of the most well-known framework to create cross-platform apps is Electron. In it you write your app in Javascript or Typescript. This code runs in a node environment and the GUI is displayed in a browser. Like this, the app can be ported easily to different operating systems. Even…

A fast and efficient blockchain created by the lab of prof. Bryan Ford.

As we all know, writing tests when developing software is very important¹. Indeed, most modern programming environments have frameworks to write and run tests, sometimes even in the standard tooling: pytest for Python, cargo test for Rust, go test for Go, etc. Let’s set aside the actual writing of the…

In response to the COVID-19 disease that has stormed the world since early 2020, many countries launched initiatives seeking to help contact tracing by leveraging the mobile devices people carry with them. The Federal Office of Public Health (FOPH) commissioned the effort for Switzerland, which resulted in the official SwissCovid…

I’m still working on my fledger project. It’s goal is to create a node for a decentralized system directly in the browser. For this I want the following: Works in the browser or with a CLI: have a common codebase but use different network implementations Direct browser to browser communication:…

For a long time I tried to understand what Proof-of-History brings to the table. What is it useful for? What problem does it solve? At the beginning of may 2022, Victor Shoup, who is a renowned cryptographer and currently working at DFinity, took a deep dive into Proof of History.…

Lightarti is a mobile library developed in Rust, in collaboration with the SPRING lab at EPFL, the Tor team, and the original Arti library team.

Disco is a framework to implement machine learning algorithms that run in a browser. This allows testing new privacy-preserving decentralized ML algorithms.

The problem Here is a common scenario we have all run into: you need to communicate some piece of secret information, say a password, to another person. Perhaps it’s on-boarding a new colleague, or to allow access for a partner. But you don’t want to compromise this secret by transmitting…

The Tandem / Monero project is a collaboration with Kudelski. It secures private keys in a privacy-preserving way.

Basics The builder pattern is a well known coding pattern. It helps with object construction by having a dedicated structure to help build the other. It is usually used when many arguments are required to build one. The example codes are written in Rust, but the concepts behind these can…

One of the ways public blockchains are touted is that they can replace your bank account. The idea is that you don’t need a central system anymore, but can open any number of accounts, as needed. However, as there is no central place, it is sometimes difficult to know how…

Today it’s something about actual hardware, not just software. For Christmas I took a long LED-strip and hooked it up to an Arduino One to create some animations. But not having WiFi was a bit of a shame, because this meant you couldn’t control it from a smartphone. So I…

Some years ago, I was thinking that by directly look at code difference, I could estimate how faster it would run. I would reflect about complexity or how a given loop will be waay faster by precomputing some values. And of course, it is never that simple. Cache locality, threads…

We’re currently using OmniLedger for logging in to our Matrix-chat and to the c4dt.org website as users. This is explained in more details here: CAS-login for OmniLedger Account management in OmniLedger C4DT partner login Matrix on Mobile There were two elements missing: Automatic signup — in the current signup process,…

On my path of moving lab’s code to more human friendly program, I usually write some CLIs, to ease configuration and deployment. When developing the client, I want to test it, and see how complex it is to use it. The best language to express that is a shell as…

Many popular cloud applications collect enormous amounts of information on their users. [...] Raising awareness of the issue, and providing ways to reduce it, is a worthy goal.

I’m quite a huge fan of functional programming, since I learnt about it some years ago. I was doing imperative programming for years and was quite used to it. But learning a new way to conceptualize programs was a real pleasure. Now that I’m deep into it, I want to…

Today I Learnt (TIL): SASE [sæsɪ]- so what is it, how does it compare to a VPN, and should I use Tor? I heard about it from Ria at C4DT, who told me SASE is the new VPN.It might be better than VPN and will solve all the world’s problems.…

At the C4DT Factory, one of our tasks is to develop demonstrators for research projects. The goal is to provide a quick introduction to a project, and allow visitors to interact and get a feel for the technology.

CLIs are very powerful, from the tip of fingers, you can quickly make the computer do anything you want. No need to wave your mouse around, hoping to find the right sub-sub-sub-menu where the feature you want is implemented. But it comes at a cost: for each command, you need…

I found this nice twitter thread from Vitalik Buterin, the inventor of the Ethereum blockchain: Doing a random twitter experiment just on this day. Only the 268 people I follow can reply to this tweet. Feel free to ask things and I'll talk about anything crypto or non-crypto related. —…

NaCl is one of the most used cryptography library around, and it is understandable: it is easy to use (it hides the crypto-magic used), portable (via the libsodium fork), and available in many languages. It is used by one of the project we are helping, drop, written in Rust, which…