In the last weeks Lemmy has seen a lot of growth, with thousands of new users. To welcome them we are holding this AMA to answer questions from the community. You can ask about the beginnings of Lemmy, how we see the future of Lemmy, our long-term goals, what makes Lemmy different from Reddit, about internet and social media in general, as well as personal questions.
We’d also like to hear your overall feedback on Lemmy: What are its greatest strengths and weaknesses? How would you improve it? What’s something you wish it had? What can our community do to ensure that we keep pulling users away from US tech companies, and into the fediverse?
Lemmy and Reddit may look similar at first glance, but there is a major difference. While Reddit is a corporation with thousands of employees and billionaire investors, Lemmy is nothing but an open source project run by volunteers. It was started in 2019 by @dessalines and @nutomic, turning into a fulltime job since 2020. For our income we are dependent on your donations, so please contribute if you can. We’d like to be able to add more full-time contributors to our co-op.
We will start answering questions from tomorrow (Wednesday). Besides @dessalines and @nutomic, other Lemmy contributors may also chime in to answer questions:
Here are our previous AMAs for those interested.
What have been the biggest challenges with the project over the years, both in terms of technical and non technical aspects. I’d be interesting to hear a bit of retrospective on how has the stack’s been working out, and what surprises you might’ve run into in terms of scaling and federation. What recommendations you’d make based on that and what you would’ve done differently knowing what you know now.
The stack is great, I wouldnt want to change anything. Postgres is very mature and performant, with a high focus on correctness. It can sometimes be difficult to optimize queries, but there are wizards like @[email protected] who know how to do that. Anyway there is no better alternative that I know of. Rust is also great, just like Postgres it is very performant and has a focus on correctness. Unlike most programming languages it is almost impossible to get any runtime crashes, which is very valuable for a webservice.
The high performance means that less hardware is required to host a given number of users, compared to something like NodeJS or PHP. For example when kbin.social was popular, I remember it had to run on multiple beefy servers. Meanwhile lemmy.ml is still running on a single dedicated server, with much more active users. Or Mastodon having to handle incoming federation activities in background tasks which makes the code more complicated, while Lemmy can process them directly in the HTTP handler.
Nevertheless, scaling for more users always has its surprises. I remember very early in development, Lemmy wasnt able to handle more than a dozen requests per second. Turns out we only used a single database connection instead of a connection pool, so each db query was running after that last one was finished, which of course is very slow. It seems obvious in retrospect, but you never notice this problem until there are a dozen or so users active at the same time.
With the Reddit migration two years ago a lot of performance problems came up, as active users on Lemmy suddenly grew around 70 times. You can see some of that in the 0.18.x release announcements. One part of the solution was to add missing database indexes. Another was to remove websocket support, which was keeping a connection open for each user. That works fine with 100 users, but completely breaks down with 1000 or more.
After all there is nothing I would do different really. It would have been good to know about these scaling problems earlier, but thats impossible. In fact for my project Ibis (federated wiki) Im using the exact same architecture as Lemmy.
It’s great to hear things mostly worked out. Stuff like scaling bottlenecks is definitely tricky to catch until you have serious loads on the system, but sounds like the fixes very mostly trivial validating overall design. It also looks like you managed to get a way with a fairly simple stack by leveraging Postgres and Rust. I’ve had really good experience with using pg myself, and really don’t see a point in using anything else now. You can use it both as a relation db and a document store, so it’s extremely flexible on top of being highly performant. Keeping the stack simple tends to be underappreciated, and projects often just keep adding moving pieces which end up adding a lot of overhead and complexity in the end.
2nding @nutomic, that I’m really happy with the stack.
The one that seems really magical to me, is diesel. With it we get a compile-time-checked database, that’s tightly integrated to the rust objects / code.
Every single join, select, insert, etc is checked before lemmy is even run, and it eliminates a whole category of errors resulting from mismaps.
Its made adding columns, and changing our data structures so much less error-prone than when I lived in the java-world.
Whenever we find that we’d want to do things differently, we usually do a refactor ASAP so as not to keep rolling spaghetti code. We’ve had to do this many times for the federation and DB code, and even have 2 major refactors that also add features ongoing. But luckily we’ve been able to stay in the rust eco-system for that.
As for UI, leptos didn’t exist when I built lemmy-ui, so I went with a fast react-like alternative, inferno. Its showing its age now, so @sleepless1917 is working on lemmy-ui-leptos, which hopefully will supercede lemmy-ui.
I briefly worked with Hasura which does this sort of magic to produce GraphQL API on top of Postgres. Incidentally, also written in Rust. I do like Leptos approach, it sounds similar to HTMX approach where you just treat the DOM as a dumb terminal.
Communities should be more unified across servers, especially for niche ones. I want to see an active Metroid community, I don’t give a crap what instance is hosting it (or if it’s a mostly-opaque medley of instances) so long as I’m federated with it. This is probably the biggest UX misunderstanding new users have.
This should be among the first priorities. It would really help kick things off. Not only niche communities, but bigger ones as well. They represent topics of interest. I think I’ve seen a thing like macro community in one of the clients?! Could that be it?
Eternity Android client allows grouping communities into a multi community, but it only helps on getting consolidated feed, not necessarily reaching the same people
the Summit app does it too
Being able to view “all” communities with the same name across all instances would be so nice.
Consolidation isn’t always a good thing, communities on different instances will have different styles and trends, and that’s a good thing. The benefit of federated social media is just as much in local instances as it is in federation, unique niches are going to have unique comments even if the post is the exact same.
I think the benefit of federation is that nobody controls the whole ecosystem. The downside of federation is splintering.
It does not have to be something mandatory…
I mean, there could be some form of “metacommunities”, something like being able to group multiple communities together in a “view” that shows them to you visually as if they were a single community despite being separated. Bonus points if everyone can make their own custom groupings (but others can subscribe to them… so there can be some community-managed groupings).
In theory you could have multiple “metacommunities” for the same topic still… but at least they could be sharing the same posts if they share communities. I feel grouping like this would be helpful because small communities feel even smaller when they are split.
I think reddit has something similar to that, multireddits or something I think they are called.
Piefed has feeds that achieve exactly that: https://lemmy.dbzer0.com/post/38733273?scrollToComments=true
Having distinct communities is a feature, not a bug. If two cities set up their own lemmy instances, say
lemmy.sao_luis.br, andlemmy.lagos.ng, they can each have anewscommunity, without them overlapping.Do a search for metroid, and subscribe to whichever ones you like.
It would still be a huge benefit, especially for more niche topics, if we had something like a federation-wide comm like
/f/niche_hobbythat you could subscribe to instead of 20 different/c/niche_hobbycommunities.Maybe comms could opt in/out of behavior to avoid the issue you described.
This would also benefit smaller instances because few people will subscribe to their comms because they are too inactive, making it so their content never gets traction.
My biggest complaint with Lemmy is that it is too hard to group & categorize content. Sometimes I want politics, sometimes I want nerd shit, but my only three options are subscribed, local, and all, which doesn’t have any categorization unless you are on an active, niche server.
Multireddits are pretty much the only thing I miss from reddit.
Piefed has exactly that: https://lemmy.dbzer0.com/post/38733273?scrollToComments=true
Interesting, is this all manually curated like multireddits? Would also be nice to have automatic ones (with include/exclude overrides)
The problem with it just being Piefed is that Lemmy clients probably won’t bother to support it unless it becomes standard.
Is this a frontend specific thing or does it also require the Piefed backend on your instance too? If it is just frontend, I would definitely use it for desktop browsing.
Dope seeing implementation diversity resulting in experimentation and innovation. Would love to see this adopted in other Lemmy implementations too
Interesting, is this all manually curated like multireddits? Would also be nice to have automatic ones (with include/exclude overrides)
They have both
- user defined feeds, public or private
- admin defined “topics”
It’s a whole different software, backend and frontend
this post provides a good overview of this issue and possible solution. https://popcar.bearblog.dev/lemmy-needs-to-fix-its-community-separation-problem/
Proposed solution 3: Communities following communities
Really, really like that idea!
What exactly is it you’re asking for, though? A change in user behaviour towards consolidation? Some new feature of the platform similar to multi-reddits? How exactly do you suggest that should work?
Not a change in user behaviour. How about: communities on different instances with the same name appear as one community essentially. As in, all instances’ version of that community appear in your feed if subscribed, and when viewing posts in a community, all instances versions of that community are visible.
Perhaps the user can restrict to just one instance’s community or just the local instance’s community with a button (like local/all), if that’s their preference.
Good luck with [email protected] and [email protected]
+1 on registration experience being the #1 issue.
Would also be cool if we could stop 404/500ing deleted posts and instead display some indication it has been deleted. See https://en.m.wikipedia.org/wiki/Principle_of_least_astonishment.
Thanks for Lemmy! 💙
We have gone back and forth a few times on how deleted content is returned by the API, its very tricky to get right.
I’ve read the Github issues. While I could agree there’s some nuance to it, black-holing the entire thing as though it never existed is a bummer.
I think the greatest strength is that it is so compatible with other Threadyverse software like PieFed and Mbin. This brings a lot of freedom to the users.
Yes I’m very excited about the growth of other fediverse software, and a lot of the cool new features they’re adding. Its a great eco-system where we can experiment, be creative, and learn from each other.
Yes this is a major benefit of an open network. Lemmy is a very large project already, so it takes a lot of effort to implement new features, because they have to meet high standards for quality and performance and also work together with all the existing features. A project like Piefed is much smaller and can implement new features more quickly. This allows for more experimentation, and successful features can later be added to Lemmy.
Also users who are not happy with Lemmy for any reason can switch to a different platform while still interacting with those on Lemmy. So if Piefed and Mbin grow that is also a benefit for Lemmy.
the apps! the app support is really great for Lemmy
Do you guys have plans to add a spoiler tag? I post a lot of memes about tv shows that I watch, but the users complain that the post isn’t blurred.
I know I can use the NSFW tag, but this gives the wrong idea and limits the post visibility (since people can hide nsfw posts).
Hello,
Thank you for organizing this AMA!
Starting with a quite expected question: when do you think you’ll be able to release Lemmy 1.0?
Its hard to say because these things always take longer than expected. Now we are finally getting to the point where all the breaking database and api changes are almost finished. After that it will take some months to update lemmy-ui for all the backend changes and new features, and the same for all other apps. Then a testing period to fix all the problems that come up. So maybe around autumn for the final release, although lemmy.ml and some other instances may upgrade some months before already.
With the rate ppl are adding issues (and we’re finding more), is sometimes feels like it keeps getting farther away than nearer, but we’ll get there in some months.
- From a code architecture perspective, how close is Lemmy/ActivityPub to reaching its maximum capacity for posts/comments per second? Are there any ways to 10x the load ActivityPub can handle?
- With Nicole in everyone’s DMs, what does the future of spam filtering look like on Lemmy?
- There is no specific maximum capacity, in theory it can scale indefinitely with horizontal scaling. Also see my reply here regarding scaling.
- 0.19.10 already includes a fix to remove private messages when a user gets banned which should help a lot. There is an issue about disabling private messages by default, but Im not sure if that will be necessary. Also 1.0 will include a plugin system, so other devs and instance admins can write their own checks. That way spam waves can be fought in a more flexible way, without having to get a change merged into Lemmy and then waiting for a new release.
How are you?
Not bad, the swiss chard and spinach I planted recently are sprouting, so that’s got me excited.
A bit tired because my whole family is half sick. Luckily the kids are still okay to go to school.
Otherwise Im excited for this AMA, because I rarely have such direct conversations with users about Lemmy. The discussions on Github are usually quite technical.
No questions right now. Just wanted to say thank you for your hard work.
I know y’all catch a lot of shit and get hammered with requests/demands, so I wanted to let you know that your work is greatly appreciated.
Thanks for dedicating your time and energy to making a non-corporate, federated social environment possible.
Being on Lemmy has been a breath of fresh air.
Thx! Really appreciate it, and I’m glad someone thinks its worthwhile work we’re doing.
What’s something you wish it had? What can our community do to ensure that we keep pulling users away from US tech companies, and into the fediverse?
One of the biggest issue at this point is probably the registration experience. There are quite a few occurrences on [email protected] of users not sure whether their email has been validated or not, and at the moment they really need to look out for the toastify notification on their first try, later attempts won’t show it.
Most recent example: https://lemmy.ml/post/27607055?scrollToComments=true
If there could be a way to inform a user saying “your email address has been validated, please wait for an administrator to activate your account, you can reach out to them at xxx”, that would be great.
This generally goes against security best practices as it can be used for attempted user enumeration. A better version would be “we’ll send you an email with your account status if this user exists” but obviously that results in a fair amount more complexity (and cost) to implement
the password/cookie should still work even when awaiting validation, password is set before the email is sent
Enumerating users is not a security problem. It’s platform obscurantism to even suggest that it is.
Youre right, I also noticed some other problems while testing registrations:
- https://github.com/LemmyNet/lemmy/issues/5547
- https://github.com/LemmyNet/lemmy/issues/5548#issue-2949361836
For the email validation it could also make sense to send out another email saying “your email has been validated”, so its not only shown on the website.
I’d need more detail here. If registration emails aren’t being sent out correctly, we need to handle that.
These two posts should provide more details
More customization for site owners. I have an independent instance and there’s a lot of things on there that are confusing for people unfamiliar with the fefiverse or lemmy. It would also be nice to remove the donation beg at the top. I know Lemmy needs funding, but it makes it look like I’m asking for donations.
Hi, I think that Lemmy is great thank you for your hard work
I actually think that given the ads and other distorsions, and thanks to federation, Lemmy is overall actually better than reddit!
Some features I miss are:
- tags
- direct messages outside Lemmy (even if not encrypted)
- better rendering of posts on mastodon (something beyond the title only). Not sure what side is responsible for this, tho!
Keep up the good work guys!
- Tags are work in progress
- Not exactly sure what you mean by “direct messages outside Lemmy”, but in version 1.0 they will be compatible with Mastodon and other platforms
- Its a known problem with Mastodon because it only renders
Noteobjects properly, which are meant for short texts less than a paragraph. Lemmy usesPagewhich is meant for longer text. Some platforms like Wordpress (iirc) have an option to federate even long posts asNoteso that it gets rendered fully in Mastodon, but that seems like a bad idea to me. In the end its up to Mastodon how to render different types of federated content on their frontend, so it needs to be fixed by them. Here is an entire discussion about this by developers of different Fediverse platforms (including a Mastodon dev).
Thank you, great to hear all my points are being addressed! The thing about post rendering, well, I just hope a common solution is found 😊
When will users be able to frictionlessly migrate between instances without losing their posts, their comments, their history, their relationships, their reputation etc? (Without requiring the consent of the exiting instance owner, or that this server still even exists, as they sometimes don’t)
Not really a question, but something to think about is being more strict about backwards compatibility so that people don’t get burnt out on having stuff break. Coming from this post by the Tesseract dev, who did not like the breaking changes to the v3 API in 1.0: https://dubvee.org/post/2904152
To formulate that into an actual question, do you think the changes are still worth it and you’d make the same decision to break backwards compatibility?
This is all a matter of dev resources. If we had maybe 6 full-time devs, we could handle things like backwards compatibility.
People forget that lemmy, like other open source hobby projects, don’t have the resources that large corporations do. People understandably get frustrated when there’s breaking changes, but they also need to not put enterprise-level expectations on a small number of people.
If someone wanted to work on that, of course we wouldn’t be opposed, but you should know how monumental a task that would be.
I would reply directly to that post, but it looks like the admin (who is also the Tesseract dev) has completely blocked federation with lemmy.ml by IP block or useragent block. So Im going to respond here to his complaints:
Lemmy didnt have a single breaking change since version 0.19 which was released 1 year and 4 months ago. And the breaking changes in that version were quite minor. Before that was 0.18, 1 year and 6 months earlier. That version only removed websockets, so most third-party app devs who used the HTTP API didnt notice any difference. Meaning the API has been almost unchanged for over three years which is quite long for a project that hasnt reached a stable version yet. 1.0 includes all the breaking changes that were held back over the years, so that we dont need any more breaking changes for a long time.
That said it would be great if we could keep backwards compatibility with the existing API in Lemmy 1.0. Problem is with all the major changes we are doing now, it would take a huge amount of work to implement this kind of backwards compatibility. If we had twice as many fulltime developers working on Lemmy this would be doable, but our resources are very limited so we have to make some compromises.
Old user, haven’t been active recently. Where’d all this growth come from?? Another reddit refugee situation?
[email protected] started to ban people based on upvotes
[email protected] movement has motivated people to look around for European alternatives to Reddit
Blaze means the website Reddit, not the community they linked
Thought you meant pre-2023 by old user


















