Jérémie Chassaing

Jérémie Chassaing

Software Gardener

@thinkb4coding · France


Jérémie Chassaing is the author of thinkbeforecoding, a blog dedicated to Domain Driven Design, CQRS and Event Sourcing.

Funder of Hypnotizer in 1999, creator of a solution for interactive video, and BBCG in 2004, editor of PixVillage, a P2P photo sharing software. Joined Siriona in 2007 as an architect with former associates to enhance Availpro, a channel manager for independent hotels, to increase scalability and reliability to match its rapid growth.

Member of the advisory board for Microsoft Patterns & Practices book about CQRS and Event Sourcing: “A CQRS Journey” and active member of the F# community.


Thermodynamics of Software

Abstract TBA.

Two day pre-conference workshop, Jan 31 - Feb 1 2017

Functional Event Sourcing

Storing history rather than current state, Event Sourcing is a radical technique to implement Domain-Driven Design efficiently. But many stop before even trying, convinced of the difficulty to implement it.

The workshop will teach how to implement Event Sourcing. The functional approach leads to a simple, clear and production ready solution, and uncluttered domain code!

The sample will be in F#, but any language will do.


  • Event Sourcing theory and its functional flavour.
  • Code the Uno sample domain in a BDD way.
  • Discuss design decision and the link with EventStorming.
  • Implement the infrastructure using an Event Store.
  • Optimizations like keeping aggregates in memory using actors, using snapshots, ...
  • Implementing projections, the Query side of CQRS
  • Implementing side effects, interact with the outside world
  • Integrate aggregates in processes.

The goal is to experiment, feel how it work, by pairs. After each step, we’ll gather, discuss the discoveries, the rough points etc.

Requirements A laptop with a development environment. No experience with event sourcing is required. A basic knowledge of a FP language is preferred (F#, Scala, Haskell…), but latest versions of C# and Java will do.

Mel Conway

Inventor, Educator, Author of “Conway's Law”

Eric Evans

Author of “Domain-Driven Design”

Rebecca Wirfs-Brock

Responsibility-Driven Design

Udi Dahan

Founder of NServiceBus

Prof. David West

Author of “Object Thinking”

Jimmy Nilsson

Author of “Applying DDD & Patterns”

Weronika Łabaj


Debasish Ghosh

Functional and Algebraic Domain Modeling

Nick Tune

Co-author of “Patterns, Principles and Practices of DDD”

Greg Young

Creator of CQRS

Alberto Brandolini

Inventor of “EventStorming”

Felienne Hermans

Author of "Grokking Computational Logic"

Andra Sonea

Solutions Architect, Financial Services

Ken Power

Complexity Navigator

Jérémie Chassaing

Software Gardener

Scott Wlaschin

Creator of fsharpforfunandprofit.com

Avraham Poupko

Technical leader

Edwin van Wijk

Software Architect

Romeu Moura

Reasoned Schemer

Marijn Huizendveld

Nerd in a suit

Stijn Volders


Robert Smallshire

Modeller of domains, systems and processes

Mathias Verraes

Student of Systems

Michel Grootjans


Yves Lorphelin

Loves Chaos & Failures

Arnaud Bailly

Event Sourcing, Functionally

Paul Rayner

Leading DDD and BDD practitioner

Nicole Rauch

Software Developer and Development Coach

Thomas Ploch

Infinite State Machine

Cyrille Martraire

Deliberate Designer

Thomas Coopman


Yves Reynhout

The Journeylist

Oana Juncu

Agile Business DJ

Allard Buijze

Pragmatic modeller, creator of AxonFramework

Vaughn Vernon

Author, consultant, trainer


Contact us at contact@dddeurope.com for sponsor opportunities.