impl Days

Todays Info

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impl Days is a sibling event of RustFest<Paris>, sponsored by Mozilla and 1aim. impl Days is an open-ended time for Rust contributors to collaborate in an active programming session. It will take place on the two days following the RustFest talks and workshops, Monday, May 28th and Tuesday, May 29th.


Back at RustFest, we organized two days after the conference for open hacking and development. Since this was during the 2017 "impl Period", the name "impl Days" was a natural choice.

Over those two days, 30 to 40 people came together to discuss, design, and implement changes to Rust itself as well its broader ecosystem.

Plus, they got to build a Lego Death Star.

The Zurich impl Days was such a success that we decided to repeat the event here in Paris.

impl Days Paris

The event is being hosted at Mozilla Paris and Formeret Espace Cléry.

impl Days is a great chance to work directly with other Rust enthusiasts. The Rust project is supported by volunteers across the globe, and while we often rely on github comments and IRC channels for communication, the face-to-face communication enabled by an event like this can be a big productivity boost.

You may be just starting out as a Rust contributor, or you may be a long-time compiler hacker who reminisces about the days when Rust was bootstrapped atop ML. Either way, there’s plenty of tasks for all contributors at impl Days.

You do not need to buy a separate ticket for impl Days; your Rust Fest ticket will suffice. However, the impl Days venue, Mozilla Paris, is more limited in space than the main RustFest venue. Due to the increased number of interested attendees, we will also have space available at Formeret Espace Cléry at 17, rue de Cléry, 75002 Paris. It is at 10 minute walk away from the Mozilla Paris office.

Thus, everyone who plans to attend impl Days should tell us explicitly on the online questionnaire built into the RustFest ticket.

What will happen at impl Days?

Felix Klock (pnkfelix) will act as coordinator, striving to aid participants in their efforts to contribute to the Rust language, ecosystem, and community.

Felix requests that participants come to the Mozilla Paris office in the morning between 9 and 9:30 AM. We will spend some time each morning getting to know each other, and then identify tasks for participants to collaborate on. There will be coffee provided at the venue, and a break for a lunch at noon. Each of the two impl Days will start winding down around 5 PM. All participants must, with heavy hearts, vacate the Mozilla premises each day by 6 PM.

For ideas of what kinds of tasks we all might work on, check out the blog post describing Rust’s roadmap for 2018.

(We will make more detailed plans on-the-fly at impl Days itself, based on the skill sets of the people who show up to contribute.)