18-19th February 2020
Meet fellow rubyists from around the world, and expand your Ruby horizons!

The year 2020 marks the 25th Anniversary of the first release of Ruby and we are lucky (and filled with gratitude) to welcome Ruby creator Yukihiro Matsumoto who will help us open ParisRB with a Keynote speech.

We’re excited! Are you??

Here’s a little more about what you can expect in February:

For Attendees

  • great location south of Paris (reachable by Metro)
  • original content, never seen in Paris speakers
  • talks about real use cases, R&D, ecology, art, hard core programming…
  • our awesome community and unique atmosphere: no hour-long talks, pauses to socialize…

For Speakers

  • dedicated MC to handle speakers’ intros
  • dedicated Time Keeper to keep everyone on schedule
  • dedicated CFP and Rehearsals team for top-notch talks
  • travel expenses up to 300€

For Sponsors

  • dedicated communication team (social networks, reach out, video coverage…)
  • dedicated people to help you

Subscribe to our mailing list

Stay informed of news relative to Paris.rb 2020.
We will release news about the conference (new speakers, sponsors, links to articles)


Only a few left!

Tickets Information by EventLama

Early bird - 2-day Ticket Discount applied

× €124.17 (€24.83 VAT) ×

This ticket is valid for the whole conference duration (Tuesday/Wednesday)

Early Bird Student - 2-day Discount applied

× €82.50 (€16.50 VAT) ×

This ticket is only valid for current students or recent graduates who are not yet twerking, must buy before 3 December 2019

Standard - 2-day Ticket Discount applied

× €299.00 (€59.80 VAT) ×

This ticket is valid for the whole conference duration (Tuesday/Wednesday) Tickets will remain at this price until the end of January.

Standard Student - 2-day Discount applied

× €125.00 (€25.00 VAT) ×

This ticket is only valid for current students or recent graduates who are not yet twerking, must buy before 1 Feb 2020

2-Day Ticket - Late Bird Discount applied

× €599.99 (€120.00 VAT) ×

This ticket is valid for the whole conference duration (Tuesday/Wednesday) Better late than never! Glad you’ll be joining us!

The Speakers

Check out the 2018 edition to know what to expect in 2020!

We received so many amazing responses to our CFP for the 2020 Conference. It was tough to choose!

This year, we aim to have a slightly more diverse content, we also have a dedicated MC and Time Master, and we offer rehearsals for all of our speakers to ensure amazing content for our participants. We continue to value original content, real-life feedback, and research.

Thibaut Barrère

Thibaut Barrère

A polyglot programmer and data engineer who started coding in the 80s, he is an independent consultant and entrepreneur since 2005. Thibaut currently works remotely from Charente Maritime.

Moncef Belyamani

Moncef Belyamani

He helped shape best practices on various Engineering teams, across both government and private sectors. Most recently, he has been studying the sciences of human behaviour, learning, and habits to become a better and more effective person. He is also passionate about music and used to DJ regularly. (fun fact: he opened (and coded) an online record store in 2003, and hosted an online radio show between 2006 and 2011)

Ruan Brandão

Ruan Brandão

Full Stack Developer from São Paulo, Brazil, Ruan is a sociable introvert keen to develop great software and discuss how the various software we produce impact the world around us. He’s a gamer, an amateur musician and a curator of humorous tweets.

Yukihiro Matsumoto

Yukihiro Matsumoto

Ruby’s Dad.

Raphaela Wrede

Raphaela Wrede

A computer scientist from Berlin with 10 years working as a Ruby Backend Developer before moving into management a couple of years ago. A feminist and advocate for diversity and inclusion, Raphaela enjoys teaching programming to women and recently started her own studies in sociology and political science. Watch out! She’s not afraid to talk about tech and systemic issues within the industry.

Nathaly Villamor

Nathaly Villamor

A software developer based in Colombia, she’s the Ruby Bogotá Meetup leader and supports Bogotá JS and JSConf Colombia as a co-organizer.

Dmitry Vorotilin

Dmitry Vorotilin

Team lead at, he helps to scale and keep application’s response time under 150 ms. He is open source activist, Rails contributor, Poltergeist maintainer (if you remember PhantomJS) and now Cuprite maintainer which uses Chrome underneath.

Nicolas Zermati

Nicolas Zermati

Backend developer at Getaround on accounting systems. Into code, people and product; master of none. Failing and sometimes learning along the way.

Prakriti Gupta

Prakriti Gupta

Contributor of daru-view and daru projects, she is always looking to learn something new. While based in India, she participated in Google Summer of Code 2018 with @Sciruby (Ruby Science Foundation) and was an SWE Intern 2019 @Grofers. Normally, you’ll find her high on music, dancing it out.

Luca Guidi

Luca Guidi

He’s an indie OSS developer, author of @hanamirb (a web framework for Ruby) and @redis-store, and a dedicated family man based in Rome.

Daniel Fone

Daniel Fone

Having been writing Ruby/Rails for over 10 years, he now helps to organise Ruby communities in New Zealand where he lives with his wife and three kids. Much like Ruby he tries to be optimised for happiness — both his own and other people’s.

Andy Croll

Andy Croll

He’s VP of Engineering at @coveragebook and @answerthepublic, a long-time Rubyist @onerubything and he runs @brightonruby in Brighton, England. He’s also an author, speaker, conference organiser, bootstrapper and dad of twins. Basically, he’s tired a lot.


Paolo "Nusco" Perrotta

The author of “Metaprogramming Ruby” and “Programming Machine Learning”, plus a handful of popular Pluralsight trainings. He has over twenty years of experience as a developer, ranging from embedded to enterprise software, computer games, and web applications.

Getty Ritter

Getty Ritter

Core contributor of Sorbet.

Sunny Ripert

Sunny Ripert

A devout Rubyist since 2006, he is currently building the interwebz @Cults3d and @KissKissBankBank.

Salim Semaoune

Salim Semaoune

A software engineer for more than 13 years, he spent at least 11 of them toying around with Ruby.

Mélanie Bérard

Mélanie Bérard

Mélanie is a fullstack Developer at Doctolib, where she is also leading a Women in Tech initiative, something she’s obviously passionate about. She’s a former entrepreneur and is invested in building impactful products. Watch out! She’s a monitoring enthusiast!

Brittany Martin

Brittany Martin

Lead Web Developer for the Pittsburgh Cultural Trust, where her team develops the nonprofit’s ticketing and festival web applications. She is also the host of the Ruby on Rails Podcast on the 5by5 Network. Under her alter ego, Norma Skates, Brittany is the president of the Little Steel Derby Girls roller derby league.

Jon Atack

Jon Atack

A Rubyist since 2009, Jon is currently a Bitcoin Core team member and protocol researcher. After studying CS/Physics at Harvey Mudd College and an MBA at INSEAD, Jon was lead maintainer of Ransack in 2013-2016, co-editor of “This Week in Rails”, and a Rails top 100 contributor. He also wrote professional video games in assembly language, handled marketing at L’Oreal, and even organised stadium concerts in Russia.

Cyrille Courtiere

Cyrille Courtiere

CTO & co-founder of Klaxit, he’s invested in operational research, distributed computing and is a clean code enthusiast. He won’t stop programming.

Alexandre Ignjatovic

Alexandre Ignjatovic

Alexandre is currently Engineering Manager at Doctolib. He was formerly CTO at Appaloosa and R&D Director at Follow Analytics. He’s an incurable ruby developer!

Philip Poots

Philip Poots

VP of Engineering at ClubCollect, a FinTech startup in Amsterdam. Pareto product programmer. Remote advocate. Dilettante.

Anne-Sophie Rouaux

Anne-Sophie Rouaux

Anne-Sophie is based in Paris and works as a backend developer @KissKissBankBank Paris, specializing in payment systems. Best things in the world: cats, horror movies and Ruby 😻🧟‍♀️💎

Jeremy Evans

Jeremy Evans

Jeremy is a Ruby committer, currently based in Sacramento, California. He is the maintainer of Ruby ports for the OpenBSD operating system. He is also the lead developer of the Sequel database library, the Roda web toolkit, the Rodauth authentication framework, and many other Ruby libraries.


Ekechi "Iyke" Ikenna

A full-stack developer who has been enjoying coding in Ruby for a long time, Iyke is now lead developer at 42courses where he’s working with the team to bring better gamified online education to more people around the world. He’s currently based in Lagos Nigeria, and loves building cool stuff.

The Schedule

CFP is closed and Speakers are up! The full draft schedule is released below. Thank you again for all your submissions!

These are the final weeks to buy tickets, so get yours before we’re all sold out!

  • Check-in

      February 18, 2020, 8:00AM,  15 minutes

    check-in will be open until 9:00

  • Breakfast

      February 18, 2020, 8:15AM,  45 minutes

    Open to all

  • Welcome and Introductions

      February 18, 2020, 9:00AM,  20 minutes

    Address from EFREI and ParisRB

  • Keynote

      February 18, 2020, 9:20AM,  60 minutes

    Yukihiro Matsumoto

  • The games developers play

      February 18, 2020, 10:40AM,  20 minutes

    Andy Croll

    This talk will use ideas from the fields of “transactional analysis” and “moral psychology” to shine a light on the interpersonal games that play out during the every day interactions of a developer going about their daily work. Once we are able to recognise them, we are better equipped to reflect on our interactions, and engage more usefully with those around us.

    The talk combines the two academic fields, with a focus on empathy and communication - traits I believe are key to building great teams and thus great software.

    First, we hear both the internal monologue of a developer and dialogue between them and the people they interact with. I’ll be illustrating their feelings and (secretly) illustrating their lack of perspective. I’ll lean a little on the real-life cliches of the ‘working developer’.

    Then, once we introduce the models from transactional analysis, I’ll re-examine the conversations to see the emotional/ego states of the participants and illustrate the games.

  • I am altering the deal

      February 18, 2020, 11:10AM,  20 minutes

    Brittany Martin

    Imagine your legacy production Ruby application is highly dependent on a third-party API — until you learn your vendor deprecates your current connection. What do you do when you’re forced to make a change? Accept the challenge by embracing abstractions, switching libraries, feature flags, edge-case testing while developing new features. Game on.

    Will focus on: Famous example of third-party dependencies that have broken application; Abstracting the API interaction; Utilizing Ruby switching libraries; Feature flagging; Testing for edge cases (QA & customer service); and much more!

  • Monads as a clean solution to our messy code.

      February 18, 2020, 11:55AM,  20 minutes

    Nathaly Villamor

    Have you ever need to write a piece of code that can fail in so many ways that you do not know how to handle it? Do you know monads?

    Monads are a classy way to write code in a structured way, step by step, and taking care of error handling very straightforward. Sometimes we have pieces of code that are tightly coupled and hard to replace, using monads we will be able to exchange any piece of code we want.

    In addition, dry-rb is a collection of gems that intend to help developers to write clear, flexible, and maintainable code based on OOP concepts and functional programming.

    Monads are a big part of this set of gems like dry-monads and dry-transaction. I will give you a glance of these gems and the things we can do with them.

  • Lunch

      February 18, 2020, 12:20PM,  90 minutes


  • Scale background queues

      February 18, 2020, 2:05PM,  20 minutes

    Salim Semaoune

    We all went through this situation when it’s 6pm on a Friday night and your monitoring system starts to complain about the latency of your background queues.

    You start to look at your sidekiq instance then you find out that some queues are blocked and you absolutely have no idea why.

    Then you look at the code but your queues host different kind of jobs.

    Next step, you dig into your metrics and try to find the culprit. You realize then that all API calls to some thirdparties are really slow and there is nothing you can do about it.

    Your only solution now is to throw more workers in the mix.

    But wait, there must be some other solutions. HTTP servers have solved this problem for years where all the workers are blocked by slow clients.

    Non blocking IOs and event loops are proven solutions to handle such problems. What if we could build an asynchronous background job system?

  • Speeding up tests with creativity and behavioral science

      February 18, 2020, 2:35PM,  20 minutes

    Moncef Belyamani

    Once upon a time, a large and slow test suite haunted engineers on a mission to improve the lives of US veterans. Every day, they wasted time running tests locally and waiting for CI builds to finish. They threw parallelization at the problem, and eventually forgot it was supposed to be a temporary solution.

    One day, they decided to do something about it, and declared, “We will not rest, until we speed up our tests!” They found the congestion in a single file, and relieved it permanently using an unconventional method. They also discovered other ways to permanently speed up the tests. In the end, they gained an extra 15 days every year to have a direct impact on a veteran’s life.

    Through this real-life story, you’ll learn analytical approaches for finding and fixing bottlenecks in a test suite in situations where generic profiling tools can’t help. You’ll also learn how to use behavorial science to craft a persuasive message and increase team adoption.

  • Keep it clean, for years

      February 18, 2020, 3:20PM,  20 minutes

    Cyrille Courtiere

    Developer’s life in a cutting-edge market is quickly creating stuff, scaling the ones that actually work and keep some others that you simply have to. Repeat this a hundred times and either you are spending your days extinguishing fires, either you have more confidence than ever in your software.

    So what’s the key to manage complexity ? How to accumulate things without losing the capacity to innovate ? What makes a choice good, years after it has been made ? How to gradually transform things without stopping the time ?

    I will explain how we try to achieve this with Ruby, love and a little of pragmatism.

  • Breaking Silos in Product Development

      February 18, 2020, 3:50PM,  20 minutes

    Raphaela Wrede

    In this talk I am going to look closer at the negative consequences of working with dis-empowered teams in what has also become known as the feature factory organization. I will show how the most innovative product companies of today seem to work very differently, and talk about two examples from my personal career that have been very eye-opening in that regard. With this talk I hope to encourage people with an engineering background to make themselves more familiar with “state-of-the-art” product management to help make our software product companies more successful together.

  • Ethics in software development

      February 18, 2020, 4:35PM,  20 minutes

    Ruan Brandão

    Software has taken over the world. Many aspects of our lives and of how society works are controlled by software.

    This brings a big questioning: How can we assume the great responsibilities that come with this great power of making software? In this talk I will discuss how we can answer that and show some ethical and moral decisions we must make when creating software. What can be considered ethical? What is the moral responsibility of the person who writes the code about effects that this code may have on society?

    The goal of this talk is to make us think about our craft of making software in an ethical way.

  • All-in-one interactive plotting using daru-view

      February 18, 2020, 5:05PM,  20 minutes

    Prakriti Gupta

    Why only other languages have web app/Jupyter notebook plotting libraries? Need interactive plotting? No JavaScript code again, please! With daru-view, you get to plot Google charts, Highcharts, HighMaps, HighStock, Datatables, D3.js and compare them using only few a lines of Ruby. Amazing, Right?

    daru-view is developed as a plugin-gem for daru and is designed for interactive plotting of charts and tables. It is basically developed but not limited to the visualization of daru dataframes and daru datavector. We can provide other inputs too like Array, Array of Array, hashes, etc.

    Overview of daru-view (
    Enhancements in GSoC 2018 (
    daru-view IRuby notebook examples (

    HighCharts official (

  • Dreaming of intelligent machines

      February 18, 2020, 5:50PM,  20 minutes

    Paolo "Nusco" Perrotta

    Computer programming comes from a dream and a war. The dream is the notion that a machine can think. The war is an intellectual clash between two rival factions.

    The first faction, the “symbolists”, gave us modern programming languages. The other faction, the “connectivists”, were disgraced for tens of years–only to come back with a vengeance a few years ago, wielding the magical results of modern deep learning.

    That epic war of ideas lasted for over 60 years, and it shaped today’s computing. It involved a lot of geeky inventions, technical challenges, and good old-fashioned human flaws. It’s an amazing story, and every programmer should know about it.

    Let me tell you that story, with some juicy technical details.

  • Wrap-Up Day 1

      February 18, 2020, 6:20PM,  30 minutes

    Feel free to mingle!

  • Check-in

      February 19, 2020, 8:00AM,  15 minutes

    check-in will be open until 9:00

  • Breakfast

      February 19, 2020, 8:15AM,  45 minutes

    open to all

  • Keynote

      February 19, 2020, 9:00AM,  60 minutes

    Luca Guidi

  • Rediscovering Ruby

      February 19, 2020, 10:20AM,  20 minutes

    Philip Poots

    Is it possible to fall out of love with a programming language? The seven-year itch led me away from Ruby, enticed by languages that promised to give me what Ruby couldn’t.

    Come and listen to a journey in search of productivity, efficiency, and effectiveness which led to some interesting places. From back-end to front-end and back again; from framework to brain work; from ease and complexity to difficulty and simplicity. From Rails to Ember to Elm to Ruby. A newfound appreciation for what was always there but lay unnoticed.

  • Running a government department on a Roda/Sequel stack

      February 19, 2020, 10:50AM,  20 minutes

    Jeremy Evans

    When most people think of government programming, they don’t think of Ruby, and certainly not Ruby without Rails. This presentation will examine my government department’s transition to Ruby and Rails, and our gradual transition off Rails, first to Sequel and Sinatra, and later to Roda. We’ll discuss the technical reasons behind the transitions, and the advantages we’ve found using our current Roda/Sequel stack.

  • Managing knowledge among the wildest animals - fullstack developers - in their natural habitat, a codebase of 200 LOC

      February 19, 2020, 11:35AM,  20 minutes

    Mélanie Bérard, Alexandre Ignjatovic

    The Doctolib mission is to improve the healthcare system globally. Today, it is used by more than 30 millions people in France and Germany. Behind the patient and practitioner platforms, 60 developers are working hard to improve the service. The software engineering team has experienced a 100% growth over the past year and further growth is expected.

    In a context where teams have to assimilate new joiners pretty fast, how do we manage to onboard them on our ruby on rails stack? Half of our new joiners don’t know anything about ruby when they arrive. Find out our strategy to help new joiners be as productive as possible in less than 3 months.

    Once they are productive, we still have to work on the same code in our monolith. How do we manage to share the knowledge when we - software engineers - don’t like to write anything but code? We tried many things, we’ll share what has worked best like our Gotcha, automatic comments on pull request, or our Starsky & Hutch mentoring programs.

  • What could go wrong? The science of coding for failure

      February 19, 2020, 12:05PM,  20 minutes

    Daniel Fone

    Software development is the anticipation of a thousand dangers: regressions, edge-cases, exceptions, attacks, downtime, the list is endless. The first part of this talk draws from a range of disciplines to build and test a simple model for quantifying danger. As we bump into some of the pitfalls of the model, we’ll also explore what neuroscience tells us about decision making. Finally, we’ll work through a number of practical and familiar code problems, while also catching some mental fallacies along the way. There will be at least one science.

    My goal is to help every developer ask a little more critically: what could go wrong? Not only so we can make better decisions, but also so we can disagree more rigorously about the dangers inherent in our software projects.

  • Lunch

      February 19, 2020, 12:30PM,  90 minutes


  • Discovering the magic of Software development, and helping others discover it too

      February 19, 2020, 2:05PM,  20 minutes

    Ekechi “Iyke” Ikenna

    A lot of people learn to code for different reasons. For a lot of people I know, it’s not just the love of technology and creating things. It’s also about how much social change it can bring about in their lives. In a place like Nigeria with very high unemployment, expensive and spotty internet, poor electricity supply are a few hurdles some developers have to scale to teach themselves to code and join the profession of their dreams

  • Kiba ETL: feedback on OSS / open-core sustainability for a Ruby gem

      February 19, 2020, 2:35PM,  20 minutes

    Thibaut Barrère

    It’s pretty easy to get burned out in OSS, as we all know! Since starting working on Kiba ETL (a ruby data processing framework) in 2015, I made a number of decisions to avoid this at all cost, and make sure my research on this would be funded sustainably, in a way or another.

    In this talk, I’ll give feedback on which conscious design decisions & trade-offs I made over time, I will explain the various business issues (legal, billing, hosting, licensing, pricing) I met on the road, and I will explain where I stand at the moment.

  • A poignant look back at "why the lucky stiff's" legacy

      February 19, 2020, 3:20PM,  20 minutes

    Sunny Ripert

    A look back to why the lucky stiff, a quirky and unique developer who helped shape the Ruby community. 10 years later, what is _why’s legacy?

  • Story of an haemorrhage

      February 19, 2020, 3:50PM,  20 minutes

    Anne-Sophie Rouaux

    You wake up one morning and realise your test suite randomly fails on your CI for no apparent reason. At first, you stay in denial and just re run your test suite again and again, waiting for some luck.

    Day after day, the disease spreads and finally becomes out of control: your test suite does not succeed anymore.

    You have to face the truth: there is something wrong with your test suite 😱

    This talk will tell the story of our own test suite debugging, why we had ourselves in this scary situation and what we learned thanks to it.

  • Modern headless testing in XXII century

      February 19, 2020, 4:35PM,  20 minutes

    Dmitry Vorotilin

    Do you write tests? Of course you do, otherwise you’d get tons of errors after each deploy because Ruby is super dynamic.

    Do you write integration tests? I bet you should but they are slow right? They are unless you use new capybara driver - Cuprite and Ferrum which controls Chrome by devtools protocol.

    I will tell you why Selenium is slow. How to write reliable tests that work. What CDP (Chrome devtools protocol) is and how to use to control Chrome and finally how to save time and debug your tests.

  • Sorbet: Practical Gradual Type-Checking For Ruby

      February 19, 2020, 5:05PM,  20 minutes

    Getty Ritter

    In June 2019, Stripe open-sourced Sorbet, a fast and powerful type checker for Ruby and a tool that has come to be indispensable for writing Ruby code at Stripe. We’ll discuss why and how we built Sorbet, including how specific choices and tradeoffs affected its design and adoption, as well as the experiences we’ve had in adopting, using, and open-sourcing Sorbet, and where we plan to take Sorbet from here.

  • The first feedback we get...

      February 19, 2020, 5:50PM,  20 minutes

    Nicolas Zermati

    … is from ourselves. I will share the true story of a bug. By looking at it across different realities, we’ll try to focus on the what our guts tell us. I’ll try to show you that emotions offer valuable feedback. This is a story about stress, uncertainty, and trust. It’ll be a warning about blind spots. And, it will promote well-known practices that we can use in response to this feedback.

  • Wrap-up Day 2

      February 19, 2020, 6:20PM,  15 minutes

    Stay and Mingle!

  • Afterparty

      February 19, 2020, 7:00PM,  200 minutes

Getting There

The closest Metro stop is Villejuif-Louis Aragon on Metro Line 7 (the pink line)

If you’re flying into Paris, the closest airport is Orly, which also has a Tram (T7 - brown) connecting you directly between Orly Airport and Villejuif




A community platform for people to share recipe ideas and cooking tips because cooking is the key to a happier and healthier life for people, communities and the planet


The EFREI is a French private engineering school located in Villejuif, Île-de-France, at the south of Paris. Its courses, specializing in computer science and management, are taught with support from the state. Students who graduate earn an engineering degree accredited by the CTI.


Hexagonal Consulting

Hexagonal Consulting has been developing projects for top clients in France and supporting the ruby community for more than 7 years


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Getaround (formerly Drivy)

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Klaxit is the biggest daily carpool network in France with 2 million rides offered each day and over 300 clients in the public and private sectors


Providing recruitment solutions to companies to bring in young talent and offering career center software to higher education institutions in Europe



Dependable Redis hosting for developers who need automated backups, monitoring, fail-safe replication and automatic failovers -- available on AWS and Heroku

Want to get involved and help support ParisRB Conf 2020? We'd love to hear from you.

Contact us for sponsorship opportunities


Thibaut Assus


Sylvain Abelard


Marianne Gillogly


Michel Martens


Patrice Cadiot


Abdeljalil Ourika