Getting Involved

LLVM welcomes contributions of all kinds. To get started, please review the following topics:

Contributing to LLVM

An overview on how to contribute to LLVM.

LLVM Developer Policy

The LLVM project’s policy towards developers and their contributions.

LLVM Code-Review Policy and Practices

The LLVM project’s code-review process.

LLVM Community Support Policy

The LLVM support policy for core and non-core components.

Sphinx Quickstart Template

A template + tutorial for writing new Sphinx documentation. It is meant to be read in source form.

How to submit an LLVM bug report

Instructions for properly submitting information about any bugs you run into in the LLVM system.

LLVM Bug Life Cycle

Describes how bugs are reported, triaged and closed.

LLVM Coding Standards

Details the LLVM coding standards and provides useful information on writing efficient C++ code.

LLVM GitHub User Guide

Describes how to use the llvm-project repository and code reviews on GitHub.

Bisecting LLVM code

Describes how to use git bisect on LLVM’s repository.

Policies on git repositories

Collection of policies around the git repositories.

Development Process

Information about LLVM’s development process.

Creating an LLVM Project

How-to guide and templates for new projects that use the LLVM infrastructure. The templates (directory organization, Makefiles, and test tree) allow the project code to be located outside (or inside) the llvm/ tree, while using LLVM header files and libraries.

How To Release LLVM To The Public

This is a guide to preparing LLVM releases. Most developers can ignore it.

How To Validate a New Release

This is a guide to validate a new release, during the release process. Most developers can ignore it.

How To Add Your Build Configuration To LLVM Buildbot Infrastructure

Instructions for adding new builder to LLVM buildbot master.

Release notes for the current release

This describes new features, known bugs, and other limitations.

Forums & Mailing Lists

If you can’t find what you need in these docs, try consulting the Discourse forums. There are also commit mailing lists for all commits to the LLVM Project. The LLVM Community Code of Conduct applies to all these forums and mailing lists.

LLVM Discourse

The forums for all things LLVM and related sub-projects. There are categories and subcategories for a wide variety of areas within LLVM. You can also view tags or search for a specific topic.

Commits Archive (llvm-commits)

This list contains all commit messages that are made when LLVM developers commit code changes to the repository. It also serves as a forum for patch review (i.e. send patches here). It is useful for those who want to stay on the bleeding edge of LLVM development. This list is very high volume.

Bugs & Patches Archive (llvm-bugs)

This list gets emailed every time a bug is opened and closed. It is higher volume than the LLVM-dev list.

LLVM Announcements

If you just want project wide announcements such as releases, developers meetings, or blog posts, then you should check out the Announcement category on LLVM Discourse.

Online Sync-Ups

A number of regular calls are organized on specific topics. It should be expected that the range of topics will change over time. At the time of writing, the following sync-ups are organized. The LLVM Community Code of Conduct applies to all online sync-ups.

If you’d like to organize a new sync-up, please add the info in the table below. Please also create a calendar event for it and invite to the event, so that it’ll show up on the LLVM community calendar. Please see Guidance on what to put into LLVM community calendar invites for more guidance on what to add to your calendar invite.

Table 118 LLVM regular sync-up calls



Calendar link

Minutes/docs link

Loop Optimization Working Group

Every 2 weeks on Wednesday




Every 2 weeks on Thursday

ics gcal


ML Guided Compiler Optimizations



LLVM security group

Monthly, every 3rd Tuesday

ics gcal



Weekly, on Wednesday



Multiple meeting series, documented here


Multiple meeting series, documented here

LLVM Alias Analysis

Every 4 weeks on Tuesdays



LLVM Pointer Authentication

Every month on Mondays



LLVM Embedded Toolchains

Every 4 weeks on Thursdays

ics gcal


Clang C and C++ Language Working Group

1st and 3rd Wednesday of the month



LLVM SPIR-V Backend Working Group

Every week on Monday

Meeting details/agenda

SYCL Upstream Working Group

Every 2 weeks on Mondays


Meeting details/agenda

Floating Point Working Group

Every 3rd Wednesday of the month

ics gcal

Meeting details/agenda:

Vectorizer Improvement Working Group

Every 3rd Thursday of the month


Meeting details/agenda:

Past online sync-ups

Some online sync-ups are no longer happening. We keep pointing to them here to keep track of the meeting notes and in case anyone would want to revive them in the future.

Table 119 LLVM no-longer-happening sync-up calls



Calendar link

Minutes/docs link

Scalable Vectors and Arm SVE

Monthly, every 3rd Tuesday

ics gcal


MemorySSA in LLVM

Every 8 weeks on Mondays

ics gcal



Every 2nd Tuesday of the month


Meeting details/agenda

Vector Predication

Every 2 weeks on Tuesdays, 3pm UTC


MLIR design meetings

Weekly, on Thursdays


Office hours

A number of experienced LLVM contributors make themselves available for a chat on a regular schedule, to anyone who is looking for some guidance. Please find the list of who is available when, through which medium, and what their area of expertise is. Don’t be too shy to dial in!

Office hours are also listed on the LLVM community calendar. Of course, people take time off from time to time, so if you dial in and you don’t find anyone present, chances are they happen to be off that day.

The LLVM Community Code of Conduct applies to all office hours.

Table 120 LLVM office hours


In-scope topics




Kristof Beyls

General questions on how to contribute to LLVM; organizing meetups; submitting talks; and other general LLVM-related topics. Arm/AArch64 codegen. LLVM security group. LLVM Office Hours.

Every 2nd and 4th Wednesday of the month at 9.30am CET, for 30 minutes. ics


English, Flemish, Dutch

Alina Sbirlea

General questions on how to contribute to LLVM; women in compilers; MemorySSA, BatchAA, various loop passes, new pass manager.

Monthly, 2nd Tuesdays, 10.00am PT/7:00pm CET, for 30 minutes. ics gcal


English, Romanian

Aaron Ballman (he/him)

Clang internals; frontend attributes; clang-tidy; clang-query; AST matchers

Monthly, 2nd Monday and 3rd Friday of the month at 10:00am Eastern and again at 2:00pm Eastern, for 60 minutes. ics gcal


English, Norwegian (not fluently)

Johannes Doerfert (he/him)

OpenMP, LLVM-IR, interprocedural optimizations, Attributor, workshops, research, …

Every week, Wednesdays 9:30am (Pacific Time), for 1 hour. ics

MS Teams

English, German

Tobias Grosser

General questions on how to contribute to LLVM/MLIR, Polly, Loop Optimization, FPL, Research in LLVM, PhD in CS, Summer of Code.

Monthly, last Monday of the month at 18:00 London time (typically 9am PT), for 30 minutes.

Video Call

English, German, Spanish, French

Anastasia Stulova

Clang internals for C/C++ language extensions and dialects, OpenCL, GPU, SPIR-V, how to contribute, women in compilers.

Monthly, 1st Tuesday of the month at 17:00 BST - London time (9:00am PT except for 2 weeks in spring), 30 mins slot.


English, Russian, German (not fluently)

Alexey Bader

SYCL compiler, offload tools, OpenCL and SPIR-V, how to contribute.

Monthly, 2nd Monday of the month at 9:30am PT, for 30 minutes.


English, Russian

Maksim Panchenko

BOLT internals, IR, new passes, proposals, etc.

Monthly, 2nd Wednesday of the month at 11:00am PT, for 30 minutes.


English, Russian

Quentin Colombet (he/him)

LLVM/MLIR; Codegen (Instruction selection (GlobalISel/SDISel), Machine IR, Register allocation, etc.); Optimizations; MCA

Monthly, 1st Wednesday of the month at 8.00am PT, for 30 minutes. ics gcal

Google meet

English, French

Phoebe Wang (she/her)

X86 backend, General questions to X86, women in compilers.

Monthly, 3rd Wednesday of the month at 8:30am Beijing time, for 30 minutes.

MS Teams

English, Chinese

Amara Emerson

GlobalISel questions.

Monthly, 4th Wednesday of the month at 9:30am PT, for 30 minutes.

Google meet


Maksim Levental and Jeremy Kun

MLIR newcomers and general discussion (livestreamed)

Every two weeks, Wednesdays at 2:00pm US Pacific, for 90 minutes.

Livestream chat or Google meet


Renato Golin

General LLVM, MLIR & Linalg, distributed computing, research, socials.

Every first Tuesday of the month, 11:00am UK time, for 60 minutes.

Google meet

English, Portuguese

Rotating hosts

Getting Started, beginner questions, new contributors.

Every Tuesday at 2 PM ET (11 AM PT), for 30 minutes.

Google meet


Guidance for office hours hosts

  • If you’re interested in becoming an office hours host, please add your information to the list above. Please create a calendar event for it and invite to the event so that it’ll show up on the LLVM community calendar. Please see Guidance on what to put into LLVM community calendar invites for more guidance on what to add to your calendar invite.

  • When starting an office hours session, consider typing something like “Hi, I’m available for chats in the next half hour at video chat URL. I’m looking forward to having conversations on the video chat or here.” on the LLVM chat channels that you are already on. These could include:

    Doing this can help:
    • overcome potential anxiety to call in for a first time,

    • people who prefer to first exchange a few messages through text chat before dialing in, and

    • remind the wider community that office hours do exist.

  • If you decide to no longer host office hours, please do remove your entry from the list above.


Users and developers of the LLVM project (including subprojects such as Clang) can be found in #llvm on The channel is actively moderated.

The #llvm-build channel has a bot for LLVM buildbot status changes. The bot will post a message with a link to a build bot and a blamelist when a build goes from passing to failing and again (without the blamelist) when the build goes from failing back to passing. It is a good channel for actively monitoring build statuses, but it is a noisy channel due to the automated messages. The channel is not actively moderated.

In addition to the traditional IRC there is a Discord chat server available. To sign up, please use this invitation link.

Meetups and social events

Besides developer meetings and conferences, there are several user groups called LLVM Socials. We greatly encourage you to join one in your city. Or start a new one if there is none:

How to start LLVM Social in your town

Community wide proposals

Proposals for massive changes in how the community behaves and how the work flow can be better.

Moving LLVM Projects to GitHub

Proposal to move from SVN/Git to GitHub.

Bugpoint Redesign

Design doc for a redesign of the Bugpoint tool.

Test-Suite Extensions

Proposals for additional benchmarks/programs for llvm’s test-suite.

Variable Names Plan

Proposal to change the variable names coding standard.

Vector Predication Roadmap

Proposal for predicated vector instructions in LLVM.

LLVM community calendar

We aim to maintain a public calendar view of all events happening in the LLVM community such as Online Sync-Ups and Office hours. The calendar can be found at and can also be seen inline below:

Note that the web view of the LLVM community calendar shows events in Coordinated Universal Time (UTC). If you use Google Calendar, consider subscribing to it with the + button in the bottom-right corner to view all events in your local timezone alongside your other calendars.

Guidance on what to put into LLVM community calendar invites

To add your event, create a calendar event for it and invite on it. Your event should then show up on the community calendar.

Please put the following pieces of information in your calendar invite:

  • Write a single paragraph describing what the event is about. Include things such as who the event is for and what sort of topics are discussed.

  • State explicitly that the LLVM Community Code of Conduct applies to this event.

  • Make it clear who:

    • the organizer is.

    • the person to contact is in case of any code-of-conduct issues. Typically, this would be the organizer.

  • If you have meeting minutes for your event, add a pointer to where those live. A good place for meeting minutes could be as a post on LLVM Discourse.

An example invite looks as follows

This event is a meetup for all developers of LLDB. Meeting agendas are posted
on discourse before the event.

Attendees are required to adhere to the LLVM Code of Conduct
( For any Code of Conduct reports,
please contact the organizers, and also email

Agenda/Meeting Minutes: Link to minutes

Organizer(s): First Surname (