OCaml hacking session at MIT, Cambridge *US*, on June 6th

I am happy to announce an OCaml hacking session in the evening of June 6th in the other Cambridge (MA, US). The event will take place at MIT, between 17:00 and 23:30, in the room 3-133. Access instructions can be found at:


This event, organized by Clément Pit-Claudel, Thomas Bourgeat and myself, is open to all OCaml programmers, advanced or beginners. Attendees will be encouraged and assisted in making a contribution to an OCaml open source project, including in particular the OCaml compiler implementation itself – we will propose a list of tasks and project ideas, and try to help in providing technical advice, feedback and guidance for contribution.

Coming with a project in mind is also welcome, on the compiler codebase or any other OCaml codebase. Many blocks of the OCaml ecosystem would benefit from contributions, including documentation contributions and the https://ocaml.org website. If you were waiting for an opportunity to scratch an OCaml-y itch in a friendly place, there it is!

Event implementation details are still being arranged, but we are not planning on having food at the event itself. We may go out in groups around dinner time, but feel free to eat beforehand or bring your own food.

Please feel free, of course, to ask any question here.


this is getting confusing… :slight_smile:

Really glad to see more events happening! Feel free to edit or otherwise use https://github.com/ocamllabs/compiler-hacking/wiki/Things-to-work-on as is helpful.

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@gasche I have some OCaml stickers if you’d like some…

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I would be happy to distribute stickers, but I’m not sure whether you happen to be in the area and/or whether they could be shipped on time.

In term of things to work on, I was thinking that I could write a list of points that could be improved in the reference manual if there was some interests in working on the documentation side.

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Yes, please! That would be very nice, and would help the other events as well. Could you create them as a Mantis issue with the junior_job tag? (It may or may not be appropriate to create several issues, do as you think is best.) One such task could be, in fact, to review your pull-request on generalization and the value restriction that, if I remember correctly, is still in limbo.

I have added few mantis tickets for the manual that felt reasonably sized for one or few compiler hacking sessions. I would rather have small issues that can be resolved reasonably atomically than another behemoth like MPR#6676 that probably would require few weeks of full time work, at the very least. In particular, this may suggest that splitting 6676 extension by extension or thematically may be a good idea, to both break it down in smaller steps and elicit more specific discussions.

Concerning, my PR for a new manual chapter on the weak value restrictions and other restriction on polymorphic functions reviews are indeed very welcome. I am not sure if I would qualify it of a junior job (maybe?), but I have added at least a manual tag to the corresponding Mantis ticket.

Just bought my bus tickets! :grinning:


If there will be some IRC channel or other online presence, please let us know here!

(planning a hacking session from Cambridge, WI, US…)

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I’ll set up a wiki page with resources, and a wiki page to log information there about what people are doing. You should feel free to use the same wiki page and add content to the same log.

We can of couse use an IRC channel (#ocaml-hackaton on Freenode?), but I don’t expect to personally have any activity there, because in my experience I’d spend most of the time looking over people shoulders or answering IRL questions. Still if we can crowd-source some of the questions/answers work to the IRC, I guess that would be very nice. Let’s do it!

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In fact maybe we could just use #ocaml? I’ll ask the regulars there.

To cut down on the amount of work I’ve accidentally asked you to do, I’ll note that https://github.com/ocamllabs/compiler-hacking/wiki
exists already!

In case that particular URL is too ocamllabs-specific, it’s only because we’ve had compiler sessions locally. Now that they’re springing up all over, we’re most happy to move that over somewhere more central for others to use as a resource as well (perhaps in the ocaml/ org?)

The idea of putting “our” log on the compiler-hacking wiki did not previously occur to me, but I see nothing wrong with it (I don’t think the specifity of the URL is a particular problem; the American log would start with a mention of where it happened and that’s fine).

One thing though: although I of course point to the material created for Cambridge-actually-on-the-Cam sessions, my idea of having a different wiki page was also that I would use them to write stuff that is not on the ocamllabs wiki, and also emphasize the tasks offered differently (in general I think that many of the tasks of the ocamllabs wiki are too ambitious for a one-night thing; they might make sense when a regular crowd comes several time, or thanks to the superpower of Jeremy/Leo/Jérémie etc., but I don’t see myself throwing beginners at them). I could of course edit the ocamllabs wiki with that content, but I don’t think it is such a good idea, given that obviously the people that created it are comfortable with the current presentation. So I think for content differences parallel pages are better than concurrent edition – although I could even use new sub-pages of the ocamllabs wiki for the alternative pages.

I’m not sure I would infer that :slight_smile: It seems to me that effort taken to make the project suggestions more beginner-friendly and appropriate to a single-night hackathon context would be welcome. An actual, current Cambridge-on-the-Cam organizer could probably shed some light on this, though!

I think for content differences parallel pages are better than concurrent edition

Fair enough, but I’m not sure that edition would be concurrent. Again, other-Cambridge folks would know better than me!

I’ll confirm what @yomimono said – that layout was created in a different time and age, many moons ago, and the scope of the events have since expanded in practise to include more ecosystem activity as well. I’m sure we’d all be fine with more help maintaining it, and to increase its inclusiveness for a wider range of tasks.

I’m also sure that having a fragmented list of activities for these events would not be good, so we’re happy to rearrange the compiler event information as appropriate to help others contribute to the task list. Ideally if someone else wants to arrange a compiler event in (e.g.) France, they could just grab tasks from a more central list for beginners to do, rather than wading through separate wikis for Cambridge, Cambridge and Cambridge :slight_smile:

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Smaller and more beginner-oriented tasks/projects would definitely be welcomed, and would be very useful for the UK Cam events as well as others… @gasche if you would be willing to edit the existing wiki with the projects you envisage for your event, in the meantime I (and others) can work on updating the existing content too. I think a few of us have planned to update it for a while, but have had difficult keeping on top of it - more help maintaining a more general list would be much appreciated!

I’m looking to confirm the room number for tonight’s event.

On this post it says:

The event will take place at MIT, between 17:00 and 23:30, in the room 3-1331.

But on the linked access instructions, it says:

The event will take place at MIT, room 3-1331, between 5pm and 11:30pm.

Is it room 3-1331, or 4-145?

@persianturtle There was a change of room: it was initially 4-145 and we moved to 3-133 (if it says 1331 it’s a mistake, I’ll go over and fix it). I’ll add a comment on thinks, thanks!

@gemmag, @avsm: ok, I’ll work on the wiki directly. Most of the work that I expect to have the time to do anyway is to curate the “junior job” tickets on the Mantis bugtracker, which is orthogonal to the wiki content.

Thanks for hosting this, @gasche! I’m excited for compiler hacking on this side of the pond. :slight_smile: