Mailing lists vs Discourse forums: open source communities or commodities?
18:00 Thu, 06 Nov 2025
Reprinted with permission from Daniel Pocock.
The free software movement and our principles came of age in the era of mailing lists and NNTP newsgroups.
Both of these technologies have been attacked from various angles over the years. NNTP has mostly been abandoned. Mailing lists continue to exist but they are increasingly subject to both the fake discussion syndrome and the pressure from certain quarters to use a web-based platform like Discourse.
Some of the more prominent corporate-controlled open source projects have already turned off their mailing lists and migrated to Discourse, including the Fedora Project and the GNOME Project. Notice these projects have similar corporate controllers so it doesn't appear to be a coincidence that they both abandoned mailing lists.
Loss of independence and privacy
One of the first things you lose with Discourse is the ability to contact your colleagues independently. Discourse hides people's email addresses so you are forced to correspond with them through the same web site. If the Discourse has a temporary outage or if it is totally turned off like the Albanian group then you lose all contact with some people. It feels wrong to invest time developing relationships with open source collaborators, to spend time answering their questions and helping them and not be able to follow up with them in future.
On top of that, it presents practical problems: some of the people you are communicating with may be using different pseudonyms in each forum. It becomes inconvenient, hard and maybe impossible to search your inbox looking for any mail from a particular correspondent.
The second disadvantage of forum pseudonyms is that all communications you send with private or direct messages are subject to surveillance by the system administrator and moderators. Whatever benefit you hope to achieve by contributing time to the open source community, the surveillance works like a tax on your long term payback. For example, if you are hoping to offer additional paid support outside the forum, the administrators may notice you doing this and take measures to monetize your clients for themselves.
Difficulty cross-posting between communities
Sometimes there is a good reason to cross-post a discussion between two mailing lists or to CC somebody from another community on a specific thread.
You simply can't do this with Discourse unless you force every external user to sign up for a Discourse account too.
The friction this creates can be understood using Metcalfe's law: the value of any platform can be quantified as the square of the number of users.
In other words, if you have one hundred users on a Discourse forum, the value is 100^2 or it is 10,000.
Using the same formula to rate the value of a mailing list, we don't just count the number of people subscribed to the mailing list, we count everybody on the planet who has an email address. Anybody with an email address can be added to a discussion on CC. If there are one billion people with email addresses then the value of email lists, based on Metcalfe's law, is 1,000,000,000^2. That is 1,000,000,000,000,000,000.
Therefore, Metcalfe's law tells us that email remains a lot more powerful than any forum platform.
Email lists let you keep a copy of everything you contribute
Everything you contribute to an email list is automatically saved to your Sent mail folder.
Even if the email list server is shut down in future, you still have a copy of all your contributions and you can use them in any way you please.
Mailing lists and Discourse are equally unsuitable for certain tasks
When people attack an existing mailing list and demand a change to the Discourse technology, they often make over-sensationalized promises about the extent to which Discourse will solve communication problems.
In fact, in many cases I looked at, I felt that the community needs to become more effective at using related technologies like wikis, bug tracking systems and project management tools.
Discourse offers wiki markup but it isn't a replacement for a real wiki server.
Being able to click a button and close a topic in Discourse is not the same as the full workflow in a bug tracking system.
Discourse allows us to create links between topics. Bug tracking and project management software is far more advanced as it allows us to identify whether a link between two bugs is a hard dependency.
Project management tools like Redmine-Agile plugin and the lightweight Kanboard application offer a convenient Kanban board (moving cards) user interface for managing tasks. Forum technology like Discourse doesn't work that way at all.
I've heard of people spending a lot of time trying to customize Discourse to meet a particular requirement before somebody told them there is a better tool for the job.
Therefore, whenever somebody tries to start a discussion about shutting down the mailing lists and moving to Discourse, it is a good idea to try and set up one of these other technologies in parallel and just keeping the mailing list as it is.
Posts being modified and suppressed after-the-fact
Discourse gives the forum controllers a lot of power to modify, relocate and delete individual posts within any topic.
In some Discourse instances, users are permitted to modify their own posts after sending them. The user interface will usually give some visual notification to help people understand if a message was modified by the original author but they don't tell you if a message was modified by an administrator.
Some people only use this capability in a responsible way, for example, to correct broken links and typos.
However, some people make drastic changes to their messages even after other people replied to them.
This leads to situations where some replies end up looking stupid or incorrect because you can't see how they relate to earlier messages in the same thread or topic.
Discourse email mode disabled by default and leads to conflict
Proponents of Discourse will often emphasize that it is risk-free because it has an email mode like mailing lists.
By default, the email mode is disabled in every new user account and only those people who are knowledgable ever turn it on.
As a consequence, it seems a lot of people have not tried it at all.
Emails received from Discourse email mode don't show you the real email addresses of the people you are corresponding with. All replies you send go back to the Discourse forum where the administrators can monitor your conversation or cut you off on a whim.
With few people enabling it, we now have the problem that very few people have local copies of the discussions in certain communities.
If every participant has a local copy of every message then it is very risky for the administrator to try and tamper with messages in the online web archive.
A good example of this is the leaking of Armijn Hemel's resignation from the FSFE (fake FSF). The resignation email was forwarded to everybody on the FSFE misfits discussion list. The misfits deleted the message from the online message archive but everybody who was subscribed to the list still has a copy in their inbox.
Whenever somebody leaks something really important like that in a Discourse forum, it is usually disappeared before most people have time to log in and read it.
Really bad/impractical printing and archiving of Discourse threads
Each forum software works differently. Discourse forums seem to use a lot more JavaScript than other web-based forums. In particular, when you open a thread or topic, JavaScript is used to load the first few messages and it only tries to download and display subsequent messages after you start scrolling.
If you open a thread and simply click the print button it will only print the messages that are currently or recently visible in the window. It doesn't seem to download later messages and include them in a single print-out unless you very tediously scroll through the whole thread from top to bottom.
This also has negative consequences for people who want to keep a locally-searchable mirror of the thread archives. You can't easily mirror a Discourse forum with tools like wget or curl.
These limitations of the user interface are not consistent with the ethical principles that open source communities have been founded on. It creates a situation where only a small group of people have convenient use of the contact details and the full message history and everybody else is a second-class citizen.
Surveillance of browsing habits
Another sneaky consequence of any forum software is the ability of the administrator to monitor which threads each user is looking at.
In communities that are highly political this increases the power imbalances.
Knowledgable users are aware of this and if these people spend less time in the forums then it reduces the quality of the discussions.
People still need to learn email habits
Taking a couple of corporate-controlled communities and forcing them to use Discourse forums doesn't change the fact that thousands of other communities are still using their traditional email lists.
People promoting Discourse forums sometimes argue that it is too hard to teach newcomers proper email etiquette.
This is a fallacy. Back in the early days, it was even harder to teach email etiquette because we didn't have things like streaming video. In the 1990s, people had to read instructions. Today, they can watch a video recording of a conference presentation about email etiquette.
Given that people will have to use these skills in other communities, this particular argument should not be taken too seriously.
Hosting Discourse and other forums is always a bigger pain than email hosting
Hosting a mailing list requires some attention to system administration and anti-spam systems.
Hosting a Discourse forum or any other web forum creates many more attack vectors for people looking for defects in the scripts and URLs, DoS attacks and such things.
The most common mailing list systems are available in convenient packages for most Linux and BSD operating systems. Web based solutions like Discourse sometimes expect the system administrator to fly by the seat of their pants, using code that comes directly from a repository or a cloud image. In these cases, the code hasn't been checked by a package maintainer and when you download it directly into your server, you may not realize if there are any untrustworthy binary artifacts or other unexpected surprises in the code.
Communities become commodities
The net effect of a web based forum such as Discourse is that the community is reduced to commodity. People who spend time contributing worthwhile content, such as answering difficult questions from their peers, may get no benefit or recognition at all if the forum administrator rearranges and edits the threads to serve some other purpose.
Forum administrators sometimes get out of touch with who is doing the work answering questions or contributing the most useful content. Sometimes their attempts to reorganize discussions are perceived as censorship or micro-managing. The people who slap each other on the back and agree with each other might hang around but the talented people stay away.
There isn't really a dual-control mechanism: these systems don't give individual users the ability to protect their contributions from editing.
In the most catastrophic cases where there are two or more administrators, we sometimes see a shoot-out situation where they both rush to lock each other out and the fastest wins.
Forum technologies create much more granular hierarchies than mailing lists. This can impact the way users see each other and the way they communicate with each other. It casts a long shadow over the culture. █