OCaml Weekly News

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Here is the latest OCaml Weekly News, for the week of August 03 to 10, 2021.

Table of Contents

Lwt 5.4.2

Raphaël Proust announced

We are glad to announce the release of version 5.4.2 of Lwt: a bugfix-only release.


You can update to this version in opam :

opam update
opam upgrade lwt

Thanks to the contributors for finding and fixing the bugs, leading to this release. Check out the release notes (link above) for a full list.

OCaml Workshop 2021: Call for Volunteers

Frédéric Bour announced

The OCaml Workshop will be held virtually, just like last year. We are looking for volunteers to fill the role of session host.

Session Hosts

On August 27, the session hosts will assist session chairs in streaming the pre-recorded videos as well as helping and moderating the Q&A sessions. They will also be responsible for security and be ready to react to potential threats and wrongdoers.

This year there will be only one broadcast for each session, but the workshop day will be quite long. There will be six sessions, lasting one hour and a half, as well as a one hour keynote.

  • Moderating the text chats
  • Controlling microphones in the video-conferencing
  • Watching for the time
  • Performing sound checks
  • Welcoming and otherwise guiding participants

opam 2.1.0!

R. Boujbel announced

We are happy to announce two opam releases: the freshly new 2.1.0 & the LTS support 2.0.9.

What's new in opam 2.1.0?

  • Integration of system dependencies (formerly the `opam-depext` plugin), increasing their reliability as it integrates the solving step
  • Creation of lock files for reproducible installations (formerly the `opam-lock` plugin)
  • Switch invariants, replacing the "base packages" in opam 2.0 and allowing for easier compiler upgrades
  • Improved options configuration (see the new `option` and expanded `var` sub-commands)
  • CLI versioning, allowing cleaner deprecations for opam now and also improvements to semantics in future without breaking backwards-compatibility
  • opam root readability by newer and older versions, even if the format changed
  • Performance improvements to opam-update, conflict messages, and many other areas

You'll find these features presentation in the blog post ; and for a full complete you can take a look pre-releases changelogs.

What's in 2.0.9

This 2.0.9 version contains back-ported fixes, you can find more information in this blog post, especially for fish users & sandbox updates.

Tremendous thanks to all involved people, all those who've tested, re-tested, tested again, given feedback, commented on issues, tested, tested, tested again…!

The opam team 🐪

containers 3.5

Simon Cruanes announced

I'm glad to announce that version 3.5 of containers has just been released. There's a bugfix for bitvectors, and a tasteful assortment of new functions (see changelog). I want to thank all the contributors, among whom first time contributor @favonia.

The release and changelog can be found here

Short contract job for OCaml/C++ programmer

Ashish Agarwal announced

We have a small project (possibly only days of work) for an experienced OCaml and C++ programmer. If you are available for a short engagement as a contractor, please DM me. Thank you.

http-multipart-formdata v3.0.1 released

Bikal Lem announced

I am pleased to announce v3.0.1 of http-multipart-formdata. This release follows a major overhaul of the parser as well as the design of the library. Here is the summary of changes:

  1. Flatten module Part_header to part_header
  2. Implement reader/pull based parser to retrieve multipart parts, i.e. implement a streaming design. This is very useful if the HTTP file upload is large.
  3. Implement push-based incremental input model, i.e. the library is now a non-blocking multipart parser
  4. Remove dependency on IO based libs such as lwt, async since it is no longer needed due to point 3 above.

Github repo: http-multipart-formdata

API doc : API manual

wtr (Well Typed Router) v2.0.0 released

Bikal Lem announced

I am pleased to announce v2.0.0 release of wtr (Well Typed Router). wtr is a trie-based router for OCaml HTTP web applications.

v2.0.0 release adds support for specifying and matching HTTP methods in a router. So now we can do the following;

      [ {%wtr| get,post,head,delete  ; /home/about/  |} about_page
      ; {%wtr| head                  ; /home/:int/   |} prod_page

Note: we can specify single or multiple HTTP methods supported by a route.

The release also features a pretty-printer - Wtr.pp - for a Wtr.t type. This has proven to be very useful when diagnosing/understanding routing issues. Sample output below,


The manual has also been improved in this release.

New playlist just dropped

Rahul announced

Haven't watched them all yet, but these look like they'd be a great resource for anyone wanting to learn OCaml: https://www.youtube.com/watch?v=MUcka_SvhLw&list=PLre5AT9JnKShBOPeuiD9b-I4XROIJhkIU

Other OCaml News

From the ocamlcore planet blog

Here are links from many OCaml blogs aggregated at OCaml Planet.


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