[metadat]

> Rama can build end-to-end backends at any scale on its own in a tiny fraction of the code. At its core is a new programming language implementing a new programming paradigm..

Grand claims, but where are the super powerful demo apps? The getting started docs are a trickle of info..

https://redplanetlabs.com/docs/~/operating-rama.html#_access...

The "demo gallery" has a few cherry picked examples, but I don't see how this fulfills the claim of a "new paradigm". I wanted to be blown.. but this ain't it.

https://github.com/redplanetlabs/rama-demo-gallery

Oof.

[nathanmarz]

Check out twitter-scale-mastodon, which is an implementation of Mastodon's backend from scratch that scales to Twitter scale. It's more than 40% less code than Mastodon's backend and 100x less code than Twitter wrote to build the equivalent.

https://github.com/redplanetlabs/twitter-scale-mastodon

https://blog.redplanetlabs.com/2023/08/15/how-we-reduced-the...

[finnh]

> These numbers are a bit better than Twitter’s numbers. Because of how unbalanced the social graph is, getting performance this good and this reliable is not easy. For example, when someone with 20M followers posts a status, that creates a huge burst of load which could delay other statuses from fanning out. How we handled this is described more below.

Huh. I haven't written myself a twitter, but I've always assumed that this problem is solved by a mix of fan-on-write and fan-on-read. Most people are fan-on-write, but those with a follower count > $THRESHOLD are fan-on-read.

The fan-on-read set is small enough to be easily cacheable, so the extra reads required to service a follower's feed are more than compensated for by the fact that the content is in RAM in a cache.

Sounds like RedPanda went exclusively with fan-on-write. I'd be surprised if Twitter does the same - but it sounds like OP has more knowledge about this than me, so I'm happy to be educated!

[nathanmarz]

The chronological timeline at Twitter fans out on write. This makes sense when you consider that the most important application metric is the latency to load the timeline. That latency is a lot lower when you only need one query on the materialized timeline rather than a ton of queries for everyone you follow.

[finnh]

Good to learn, thanks. "Everyone you follow" isn't quite what I was saying, but I also don't use twitter so I'm doubly in the dark here.

I'm surprised that someone with, say, a Twitter problem and tens of millions of followers - the two seem to go hand-in-hand - drives tens of millions of writes every time they post. But there you go, learned something today.

[fizx]

I was tech lead on that subsystem for a little while in 2010. A lot of smart people thought about the hybrid approach, either by using the search index to drive the timeline or building a custom ring-buffer-based index of all tweets. Ultimately two systems are harder to maintain than one, custom indices are hard, and the low-complexity approach dominated a higher-performance approach.

Also, contrary to popular opinion, we didn't go down when Justin Bieber tweeted, but we did have elevated error rates when large quantities of Justin Bieber followings put pressure on the MySQL row lock of his following count. In retrospect, lock striping would have helped, but the migration would have been horrific.

[nathanmarz]

Back in the days of the fail whale, Twitter would go down when Justin Bieber tweeted because their system couldn't handle the load.

[metadat]

> Running on a real cluster

> Until Rama is publicly available, the only way to get access to the full Rama release is by applying to our private beta.

I thought it was coming out last August? What happened?

(As per your link, https://blog.redplanetlabs.com/2023/08/15/how-we-reduced-the...)

Edit: @nathanmarz that's cool you have enough interest to keep things moving with it being private. I'm only interested in open solutions for this domain, though. IMO, accepting lock-in is a lot to ask. Best wishes ~ MD

[nathanmarz]

We released the public build last August, which can be used to experiment with Rama. Details on that are at the link below. Otherwise, we're still in private beta and access to the full Rama release to run real clusters is just for private beta users.

https://redplanetlabs.com/docs/~/downloads-maven-local-dev.h...

[ntonozzi]

Here's an example of the backend code:

https://github.com/redplanetlabs/twitter-scale-mastodon/blob...

It certainly looks like it does a lot with their DSL, but as a newcomer it's really hard to parse.

[nathanmarz]

I suggest starting with the tutorial and the heavily commented examples in rama-demo-gallery, linked below.

https://redplanetlabs.com/docs/~/tutorial1.html

https://github.com/redplanetlabs/rama-demo-gallery

[mintplant]

Any examples of the Clojure version?

[nathanmarz]

All the examples in rama-demo-gallery have both Java and Clojure versions, including tests. There's also the introductory blog post for the Clojure API which builds a highly scalable auction application with timed listings, bids, and notifications in 100 LOC.

https://blog.redplanetlabs.com/2023/10/11/introducing-ramas-...

[geodel]

Well there is whole bank transfer implementation there and thoroughly commented too. Some entrepreneur can take this and run with it to create next generation banking platform.

[sokoloff]

Maybe they could call their new Clojure-based bank Nubank.

[erichocean]

Obv. Unicorn potential.

[kitd]

Tbf, the purpose of the blog is to talk about the power of Clojure/Lisp for defining the new paradigm, rather than the paradigm itself. Though the author then goes on to talk about "fragments" as the basis for the new paradigm.

The first sentence has a link to the project page which has most of the info you need.

[smackeyacky]

Not even a code sample in the article. You'd think if they were so convinced it was a new paradigm we'd see why. Makes me skeptical.

[nathanmarz]

It's an article about Clojure's influence on Rama, not an introductory tutorial on Rama. But we have plenty of code samples elsewhere:

https://github.com/redplanetlabs/rama-demo-gallery

https://github.com/redplanetlabs/twitter-scale-mastodon

https://blog.redplanetlabs.com/2023/10/11/introducing-ramas-...

https://redplanetlabs.com/docs/~/tutorial1.html

[cactusfrog]

The Clojure community is extremely cult like. I worked with a dev who tried to push Datomic, and despite the huge flaws with his system, and the fact that it was closed source, he would continuously tout how much better it was than a relational database. I don’t believe the hype.

[lispisok]

You just generalized an entire community based on one person. I can add a counter anecdote to your N=1. I'm a Clojure dev. I've used and enjoyed Datomic. Postgres is still my goto database.

[undershirt]

I know our engineering discipline is in shambles, but there are probably better ways to argue against hype without ourselves using hyperbole.

[cactusfrog]

I don’t believe I’m exaggerating. You can replace “Clojure” with “Jesus” in the linked article and it still makes sense.

[gorjusborg]

Clojure is not special in that it has some zealots.

It's easier to call others out when they aren't in the mainstream, but I'd say that there are way more mainstream cult members than these niche communities. For instance, HN itself can feel a bit cult-like. The greater tech culture feels similarly.

[hu3]

Closed source is enough reason in my book.

[jabradoodle]

N=1, I work with many pragmatic clojure devs who just want to ship working software.

[lgrapenthin]

There are no huge flaws with Datomic.