
Arnaud Bailly
Biography
Arnaud has been developing software and helping teams develop software for nearly three decades, in various technologies, contexts and roles. He is interested in everything software-related with a peculiar passion for strongly-typed functional programming.
NewCrafts Paris 2025
Typed λ-calculus for Dummies
HandsOn
This is a Hands On Lab with limited capacity.
While Functional Programming languages, FP idioms and concepts have become commonplace in many mainstream languages. But do you know the principles behind these concepts, and what makes those principles so appealing and useful? This workshop is a hopefully fun hand-on exploration on the implementation of a simple typed λ-calculus.
Attendees will interact with a program that will guide them to implement, in any language, an increasingly complex typed λ-calculus represented as S-expressions. The presenter will help them through the experiment and clarify concepts.
Previous events
NewCrafts Paris 2017
On the Mode of Existence of Software
Talk
What is software?
Is software development engineering or art? What if software "was" not? What if it could only be approximated and never been given a precise ontological definition? What if the correct paradigm to think about software was the infinite network of potentiality it creates and is part of?
This talk is an attempt at deconstructing all the representations that are commonly used to talk about software, be it building (e.g. constant reference to Christopher Alexander's work), craftmanship, engineering, science... I will try to demonstrate that software has its own specific mode(s) of existence and consequently must be addressed in specific ways, lest we stay at the doorstep of understanding it. In particular, I will criticise static views of software and specifically the mere concept there is such a thing as software design.
This talk is highly experimental, philosophic and controversial: Questions, feedback, critics and arguments are most welcomed.
NewCrafts Paris 2016
Life Beyond Relation Database in Haskell
Talk
Relation databases are great... for querying. When it comes to writing/updating data they are not so great and can quickly become the main pain point of your architecture. This talk presents how we implemented Event Sourcing at Capital Match, using Haskell as our backend language and Clojurescript as our frontend language. We shall provide a balanced diet of theory on event sourcing and the benefits of choosing such an architecture, especially in functional programming language setting, mixed with practical insights on how we implemented and deployed it at Capital Match.