jjirsa

Feels like a thread for me

I’ve run more Cassandra than anyone on the planet. Also more FoundationDB. And more Postgres than I can count. Likely 3 orders of magnitude more than you.

1. Any db at that scale requires a team. Thousands of cores is gonna be either paying saas or paying a team and I don’t care what the tech is. You’re gonna fuck up any db on the market letting your app eng run a thousand cores of Postgres or MySQL or couchbase or cockroach or tidb.

2. Cassandra at scale has a demonstrably better cost and availability slo than literally annything else I’ve ever tried to run, as long as you have a competent team. And I had a great team. But we had a great team because we understood that at million core scale it’s a core of the product and you invest in your core. But a good team of a dozen people can run a million cores at 6-8 nines, at lower cost per byte or cost per query than any db-aas you can buy online from any cloud vendor. I know this because we checked, and I’ve been ahead every time.

3. The db isnt fun to run. But it’s getting way better. If you think this is 2009, it’s not. The folks working on it in 2026 know what they’re doing and the last decade has made it measurably safer and easier.

Nothings free, but I’d bet my salary I can run damn near any company on Cassandra cheaper than any of your alternatives. Even all the vendors who keep selling against Cassandra. A competent team on Cassandra is going to beat your vendor product 90% of the time.

> Waymo is now completing 450,000 weekly driverless rides across six cities, with a peer-reviewed study showing statistically significantly lower crash rates than human drivers across 56.7 million rider-only miles. When Waymo’s vehicles were caught passing school buses, the company filed a voluntary recall within weeks. Tesla, on the other hand, is now on its second deadline extension just to tell NHTSA about FSD’s traffic violations.

That, in itself, is saying more than anything else

Congrats datastax folks. Happy for you.

Youre not far off, just use your original sentence and acknowledge that Scylla isn’t the OSS here, its the company that came in, forked a volunteer driven project, and tried to pretend its theirs:

> Or more often companies with money come to fork an open source project from the developer, and continue pretending it's their own now.

> I would say it's opposite. No one contributes to open source and the developers have to make money on the side to work on the project

You missed the important part of his sentence:

> All those open source copycat projects, using open source to get exposure then switching

The original open source here was Cassandra. Scylla exists to pick off that market share. They launch with a free license, pull customers, then swap license. The actual adoption of Scylla would have been a fraction had it been released under this license to start, which everyone understands.

> Or more often companies with money come to fork an open source project from the developer, and continue pretending it's their own now

It had already been AGPL, so it's not like they're protecting against competition. They already had a license that avoided the forking problem. This isn't protection against AWS (keyspaces likely has more OSS cassandra code in the protocol tier than it has Scylla code, if it has either). It's protection against free consumption.

Remarkable to me that ctrl-f, "Sourceforge" had 3 hits on this page. Would have expected a dozen.

Some companies have both massive files and a massive number of files

Yes! Congrats Phil!

Congrats Apple folks who worked on this, I know it’s been a long time coming

Cassandra’s jepsen is over 10 years old now.

That database spent 3-4 years primarily focused on correctness from 2018-2022.

The industry moves fast, our memories are slow. But there are millions of instances of cassandra in production across most of the fortune 500, and half of this thread has never heard of RavenDB

It’s disappointing to me that the technologist desire to experiment with new DBs continually puts naive customers at correctness and durability risk they don’t (won’t) understand.