>slack is the most trivial software you can think of

This is like saying that food service at 30k feet in a passenger airline is trivial because all the server has to do is walk up and down a narrow aisle handing out food from a cart.

Since "you see no reason this service can't be nearly as reliable as life support firmware", one of two things must be true:

1) You know something nobody else knows. In which case great, you've stumbled on a huge opportunity to go put your knowledge to work and get stupendously rich by outcompeting this "trivial" software company. Get to it, genius!

or

2) The reason you "see no reason..." is that you're unaware of one or more relevant facts.

Which of these do you think is more probable?

3) slack will get their "chat as a service" monthly fee whether the service actually works or not, so why commit to higher levels of service? We can get our users acclimated to outages and then sell them "slack Premium, for Serious Business", charge an even higher fee, and get stupendously rich all over again. This is the "growth" that investors demand, no?

The dark truth is I suspect we're moving in the opposite direction. Abstraction layers designed with that "chill, it's just a %s app" mindset are making their way into safety critical applications.

Eventually somebody is going to die because their pacemaker decided to throw cycles at mining monero.

Slack is text, channels, images, video, sound, search, audio calls, video calls, screen share (and interface share), bots, myriad integrations, and more. Calling it just "send text from one computer to another" is wrong.

I think maybe their point is that even if other pieces break, why shouldn't it be possible for the text communication to keep working?

If trying to provide all the other things besides text causes the system to be unstable, then maybe those things shouldn't have been added. We need text. We just want the other things.

Let me add more reasons: 1) Software human mistake, when some software error/exception throws much larger issues, that require manual restore with service downtime.

2) Geodistributed datacenters is VERY expensive thing, so not implemented fully.

3) Bad system design, full of "one point of failure".

> ) Geodistributed datacenters is VERY expensive thing, so not implemented fully

You buy servers on aws-us-west and aws-us-east, and sync them . How is that very expensive?

I imagine you've never actually had to solve any of these hard problems, which is why you think it's so easy to do.

That's bordering on (if not crossing into) ad-hominem.

There was no accusation of "so easy", only so not expensive and supposedly (and previously, demonstraby) solved in the last 30 years.

They may well be "hard" or even "expensive" for some definition of those two words, but if it weren't, it would defeat much of the (stated/advertised) purpose of outsourcing/cloud.

You propose just to buy servers in 2 locations to keep Slack services up? Doesn't work, when you need to store gigabytes daily and have dozen thousand reqs/sec synchronized.

Geodistributed datacenter requires multiple direct low-latency multigigabit/sec connectivity, special software to manage, test and check it, skilled devops.

I know. there's totally not a command called rsync. And "replication" is just a word you hear on star trek along with teleportation.

Although I agree with your premise, I think the delivery takes away from your point a bit.

Specifically, you risk people piling on that rsync isn't good enough in the modern world and referencing the comment criticizing Dropbox as being little more than an rsync replacement [1].

Of course, the specific tool one uses is irrelevant. The data synchronization problem may not be well solved, but it has been very well studied, with a remarkable number of good-enough options.

So, no, there isn't just one "sync" button, as the parent comment snarkily suggested, but there may be two, one where you might lose the last N seconds of chat (perhaps temporarily) and another where you lose the ability to chat entirely for those N seconds.

[1] Although it had other criticisms, such as monetization, which are, naturally, ignored.

Oh, yes, someone in Slack clicked the button “Pause” and we all are waiting, when Slack’s hero will click “Resume” :)

They very likely have all of these protections in place, and more. Large-scale outages of mature systems are almost always a cascade of small human errors that, each on their own, would have caused negligible damage. It's only when they happen to align with each other that a large disaster is realized.