Discourse Migration Guide

This document is intended to help LLVM users to migrate from the mailing lists to Discourse. Discourse has two basic ways for interaction: Via the web UI and via emails.

Setting up your account

The easiest way is to create an account using your GitHub account:

  1. Navigate to https://llvm.discourse.group/
  2. Click on “Sign Up” in the top right corner.
  3. Choose “With GitHub” on the right side and log in with your GitHub account.

Structure of Discourse

Discourse’s structure is similar to a set of mailing lists, however different terms are used there. To help with the transition, here’s a translation table for the terms:

Mailing listDiscourse
Mailing list, consists of threadscategory, consists of topics
thread, consists of emailstopic, consists of posts

Setting up email interactions

Some folks want to interact with Discourse purely via their email program. Here are the typical use cases:

  • You can subscribe to a category or topic
  • You can reply to a post, including quoting other peoples texts (tested on GMail).
  • Quoting previous topics in an reply
  • TODO: Creating new topics via email is supported but not configured at the moment. We would need to set up an email address per category and give Discourse POP3 access to that email account. This sounds like a solvable issue.
  • You can filter incoming emails in your email client by category using the List-ID email header field.

Mapping of mailing lists to categories

This table explains the mapping from mailing lists to categories in Discourse. The email addresses of these categories will remain the same, after the migration. Obsolete lists will become read-only as part of the Discourse migration.

Mailing listsCategory in Discourse
All-commitsno migration at the moment
Bugs-adminno migration at the moment
cfe-commitsno migration at the moment
cfe-devClang Frontend
cfe-usersClang Frontend/Using Clang
clangd-devClang Frontend/clangd
flang-commitsno migration at the moment
flang-devSubprojects/Flang Fortran Frontend
libc-commitsno migration at the moment
libcxx-bugsno migration at the moment
libcxx-commitsno migration at the moment
lldb-commitsno migration at the moment
llvm-adminno migration at the moment
llvm-branch-commitsno migration at the moment
llvm-bugsno migration at the moment
llvm-commitsno migration at the moment
llvm-devProject Infrastructure/LLVM Dev List Archives
llvm-devmeetingCommunity/US Developer Meeting
llvm-foundationCommunity/LLVM Foundation
Mlir-commitsno migration at the moment
Openmp-commitsno migration at the moment
Parallel_libs-commitsno migration at the moment
Release-testersProject Infrastructure/Release Testers
WiCTCommunity/Women in Compilers and Tools


I don’t want to use a web UI

You can do most of the communication with your email client (see section on Setting up email interactions above). You only need to set up your account once and then configure which categories you want to subscribe to.

How do I send a private message?

On the mailing list you have the opportunity to reply only to the sender of the email, not to the entire list. That is not supported when replying via email on Discourse. However you can send someone a private message via the Web UI: Click on the user’s name above a post and then on Message.

Also Discourse does not expose users’ email addresses , so your private replies have to go through their platform (unless you happen to know the email address of the user.)

How can my script/tool send automatic messages?**

In case you want to create a new post/topic automatically from a script or tool, you can use the Discourse API.

Who are the admins for Discourse?

See https://llvm.discourse.group/about

What is the reason for the migration?

See this email

How do I set up a private mailing list?

If needed categories can have individual security settings to limit visibility and write permissions. Contact the admins if you need such a category.

What will happen to our email archives?

The Mailman archives will remain on the web server for now.

What are advantages of Discourse over the current mailing lists?

  • Users can post to any category, also without being subscribed.
  • Full text search on the Web UI.
  • Sending/replying via the Web UI (email is still possible).
  • View entire thread on one page.
  • Categories are a more light-weight option to structure the discussions than creating new mailing lists.
  • Single sign on with GitHub.
  • User email addresses are kept private.

I have another question not covered here. What should I do?

Please contact iwg@llvm.org or raise a ticket on GitHub.