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.
- I have no idea how and which server I joined, is there any manial I can read better yet visually see how servers are connected that are federated? Thx. And when we search something does it search across all servers? Thanks.
When will anyone be able to click the following /c/books And see an agglomeration of all “books” communities on all federated server? I don’t mean multireddits Thanks!!
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)
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.
Thanks so much for doing your part to make Lemmy an active place. That’s the main thing that sets us free.
❤️
Thx! Really appreciate it, and I’m glad someone thinks its worthwhile work we’re doing.
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 @dullbananas@lemmy.ca 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.
The stack is overall amazing, but not perfect. Waiting for the Rust code to compile is sometimes very annoying, but I wouldn’t want to use a different language. And we had to implement somewhat complicated things that existing Rust libraries did not do. For example, I made the “i_love_jesus” library so Lemmy could have cursor pagination that uses indexes well and allows bringing back the “back” button, we have a few custom QueryFragment impls because of diesel’s limitations, and we have a custom migration runner to do fancy stuff (see crates/db_schema/src/schema_setup.rs).
Being a Lisper, the idea of waiting for the compiler is very jarring. :)
Are you disappointed with the way things are growing with people trying to marginalise the likes of ML and Grad?
Communities that go against hegemonic capitalist/imperialist discourse will always get marginalised. Not being able to take down those communities easily like on Reddit is a huge win by itself for Lemmy. The software offers a valuable savehaven for e.g ex r/chapotraphouse, r/genzedong etc.
Yep, the fact that Communists can build their own platform and networks free from any outside censorship on corporatized platforms is itself the strategy for building leftist spaces. The goal isn’t hurt by more non-Communists being on the overall Lemmy platform because these non-Communists can’t actually do much to shut the Communists out.
That’s a good thing, as a Communist I’m happy we have spaces.
It seems some people simply need some target to hate on. Hopefully they will learn to accept different opinions when they arent being manipulated by for-profit social media anymore.
I get a chuckle out of the “Tankie Triad” talking point some people keep using. It sounds like a villain organization from a Saturday morning cartoon.
The anti-communist witch-hunters are extremely peeved that they can’t remove our communities like they can on reddit. Overall it doesn’t bother me because I don’t work for them, and they can always go back to reddit where their views are already dominant.
Anyone trying to make the world a better place, will always be hated and hunted by some people; it’s a fact of life, and the sooner we accept it, the better.
Just wanted to say I LOVE lemmy! It’s a really positive community, the atmosphere is great and I like how it’s unique but also familiar. I really appreciate your work on it. I know this is AMA… what’s your favourite animal?
Youre welcome! Im not really an animal person, but I choose dogs.
Thx! Hard to pick a fav, but meercats are pretty cool.
Excellent choice!
Native push notifications would be awesome for Lemmy! I’m keeping my fingers crossed.
Is there a way to move myself as an user from one server to another?
You can export your settings, community follows etc and import them in another instance. Moving your existing posts and comments doesnt work well with federation.
i need to know this too
I was thinking this cold prove necessary in the context of different servers policies. Got example, if my server would change policies to something I am not willing to agree, then it would be nice to migrate to another server
This is the huge disconnect between what the fediverse is and what the users actually want.
Users want the convenience of a single entity that floats around the different instances. They want to interact with community A on instance B and also commini X on instance Y.
But most clients deal with it by letting you log in with multiple users on multiple instances
- 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.
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.
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.
Look, this is just my take – I think this is bad UX. I’m not saying federation isn’t a good idea – on the contrary, I like the idea that many different posts in the same community are all hosted on different instances. Sure, for a community like
newsit doesn’t make as much sense – fixes for this would be that some communities don’t have the behaviour I’m suggesting, or the convention is to call itsao_luis_newsor something.Who controls this universal community name system?
It’s a good question. Perhaps nobody needs to control it. Users of c/foo post on their own instance (or choose an instance to post on). Mods are responsible for posts on their own instances (as before). The difference is that when viewing c/foo, you see posts from all federated instances.
For news, politics, etc, which might cause trouble if combined, here’s a solution: Perhaps if your instance’s
c/foocommunity has the “keep separated” flag enabled, then users on your instance browsing c/foo won’t see posts from other instances, and users on federated instances won’t see your instance’s c/foo posts when browsing c/foo.
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.
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.
I think the benefit of federation is that nobody controls the whole ecosystem. The downside of federation is splintering.
Less that nobody can control the whole thing, more that you can have full control of your own thing. Basically the same thing you said, but I think it’s important to note that many niche communities thrive on Lemmy.
Many more niche communities languish because they can never get enough traction to be seen.
If I subscribe to
/c/dubstep, chances are I don’t care if it islemmy.ml/c/dubsteporlemmy.world/c/dubstep, but neither community is likely to be active because one comm on one instance needs to be the popular one for other users to sub and want to post there. What I really want is/f/dubstepI disagree, actually. The issue here is relying on communities to be active, rather than instances with a healthy size and sorting by new rather than active. Hexbear has a bunch of communities, but people sort by New so any post will have some traction.
Lemmy works best when instances rely on themselves, and not federation. Federation is a bonus, not the point itself. Thinking of this massive fediverse as a single entity would mean it’s probably better to use Reddit, anyways.
Federation should be the point. I didn’t join Lemmy to join yet another reddit-like service but with far fewer users. I joined it because I want to be on something like reddit but which no one group controls. Otherwise I’d use threads, bluesky, etc.
Federation is one side of the equation, the fact that no one person controls it relies upon the fact that it isn’t centralized into few communities. It’s a double-edged sword, the same benefit is also potentially a drawback for others.
Being able to view “all” communities with the same name across all instances would be so nice.
To be totally honest, a lot of communities aren’t big enough yet to really necessitate splitting into niche communities yet. I don’t know if gaming/Metroid is an example of one that does or doesn’t meet that. It’s just an observation.
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?
How would two communities named
news, work for say, a server about star trek, and another located in a city.Well, what is each meant to represent? Should communities be constructed around the concept of topics, or should there be a server for each topic?
And please don’t use any variant of “everybody can do it whichever they want”, because this just avoids the responsibility of offering a personal answer and shifts it to them.
Personally I think the first (communities=topics)., while servers should provide voluntary redundancy for each other in case one of the servers has an inconvenient change of policies or circumstances for the users.
But I am not on the creative team of Lemmy, so my vision might differ from theirs. Also, I’m willing to change my belief if more solid arguments are presented.
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
this post provides a good overview of this issue and possible solution. https://popcar.bearblog.dev/lemmy-needs-to-fix-its-community-separation-problem/
Who is your daddy and what does he do?
No seriously he’s retired and cooks his brain watching fox news all day. If he got off that drug for even a month he’d return to being a sweet and caring person.
Wait, I thought you’re French, dad sniffing the Fox from France?
Kindergarten cop right?
Some Lemmy clients offer the option to auto-hide posts and comments which contain certain keywords of the choice of the user. Are there any plans to implement this feature into the stock Lemmy experience?
I know it is possible to do some hacky stuff with UblockOrigin to do the same, but that is not something most know about and are willing to do.
This is currently work in progress.
What was the last post that made you really laugh?
This one by @lka1988@sh.itjust.works
What Is the airspeed velocity of an unladen swallow?
42
Now there’s a frood who really knows where his towel is 👍
African or European swallow?
I don’t know that.
[gif that lemmy imageproxy refuses to show for some reason]
Turns out the size limits for animations that we set on lemmy.ml also apply to proxied images. I would think its only for local uploads. Removed the limits now to get it working. Thanks for letting me know.
Allow < 1MB sound files
