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Comment by dorfsmay | Hacker News Reader

Note that this isn't a better nagios... It's more like Apache Storm. Think of it as grep on steroid. I've heard of several thousand events per seconds on a single server. The other advantage is that it uses a well known programing language rather than a DSL.

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It's actually a disadvantage, since it's Clojure, and Riemann requires that its operator actually knows Clojure (knowledge of dozen languages, even when some of them are functional, is not enough).

Is requiring someone to learn a programming language worse than requiring someone to learn a custom DSL? Seems a strange assertion.

A full programming language is likely more effort to learn than a custom DSL. If you're in a position where you can reuse the full programming language then it's probably better, but if you're never going to use that programming language for anything other than this one product then the DSL is probably better.

Clojure is a bigger language than small custom DSL.

The parts of Clojure required to write a config file are probably roughly the same size as a custom DSL though.

Maps and lists are gonna be maps and lists...

Except for Clojure's data model. You'll still need to understand what apostrophe ("'") does and what keyword (":foo") is.

You can do that in five minutes. You can easily spend days trying to understand some arcane, adhoc configuration syntax that someone came up with. And still get the non-trivial cases wrong.

It's a good thing that it's Clojure and not some freakish turing-complete XML-based configuration file.

Custom DSLs eventually pick up those things, anyway.

Greenspun's 10th rule? http://c2.com/cgi/wiki?GreenspunsTenthRuleOfProgramming

I had forgotten about this... Thanks!

The problem with immature DSLs are that you spend a lot if time figuring out if the bug is in the DSL or in your use of it, and lesser network effect: because they are less used, they are more buggy, there is less information and help about them out there, there are less tools you can use.

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