

Itching my programming nerve - aaco
http://armstrongonsoftware.blogspot.com/2008/06/itching-my-programming-nerve.html

======
Tichy
Interesting idea with the open source stock exchange. I always assumed that
one can't simply launch a stock exchange, it has to be highly regulated and
expensive to get into (just like not just anybody can start a bank). Not sure
if that is the case, but the "open source" part made me think, perhaps in
developing countries it could be useful. Perhaps people could just have local
stock exchanges, and the government wouldn't even care.

~~~
dpapathanasiou
_I always assumed that one can't simply launch a stock exchange, it has to be
highly regulated and expensive to get into_

Steve Wunsch tried it in the late nineties with the Arizona Stock Exchange
(<http://www.businessweek.com/1997/09/b3516129.htm>).

Interestingly, the hard part is less about regulation than market forces.

You have to have listing standards (i.e., do the companies listed really
exist, are their financial records accurate, etc.) that traders will trust,
and you need a critical mass of buyers and sellers to start using it.

~~~
wagerlabs
You don't need (want?) to launch an exchange these days. What you do is launch
a so called "dark pool", an opaque matching engine, to provide liquidity.

Then there are ECNs like <http://www.batstrading.com/>. See
[http://en.wikipedia.org/wiki/Electronic_communication_networ...](http://en.wikipedia.org/wiki/Electronic_communication_network)
and google for Island, Instinet or BATS.

~~~
Tichy
I voted you up even though I don't understand what you are talking about. But
it sounds interesting...

~~~
ntoshev
The dark pools, or liquidity platforms, match orders up before they reach the
exchange. Basically you have big orders sitting in the pool and waiting to
match up with passing traffic. These orders are not publicly visible, so you
get less price transparency than if all orders are matched through the
exchange.

------
nir
Some interesting stuff there.

Not sure about the wiki - if it doesn't fully implement _everything_ MediaWiki
does, it may be too early to compare performance (80/20 thing). CouchDB on the
other hand is _very_ promising, as a whole new DB concept.

~~~
mechanical_fish
CouchDB sounds interesting, but the wiki thing is the _opposite_ of a "killer
app" -- I'm sure it's a nice demo, but MediaWiki is a _seven year old_ app. As
a PR exercise, it just serves to enhance Erlang's unfortunate reputation as a
great language for writing prematurely optimized code that ships late. If you
want some positive PR, rebuild Twitter, and do it _before_ 2010\. Better yet,
build something new, or something profitable, or both.

They say this thing is "faster" than the current Wikipedia, but they don't
really say _how much faster_. Benchmarks are deceptive. Where's the cost-
benefit analysis -- you're asking me to have one of the world's top Erlang
hackers rearchitect an app in a language that only a handful of expensive,
talented people can understand, and for what? Will the Wikimedia foundation
save $10k per year? $100k?

And, when Wikipedia's competitors start adding features, will the foundation
discover that the cost of modifying their super-optimium Erlang app completely
outweighs the savings in server hardware? Wikimedia isn't in the telecom
industry: They don't have a monopoly, and their specs might have to change
more often than once every decade or two.

~~~
evgen
You are obviously focusing on the presentation-layer (mediawiki) and
completely ignoring the data store that everyone else is quite psyched about.

Here is what scalaris provides: distributed, fault-tolerant, replicated key-
value store (a la Dynamo/SimpleDB.) This layer can be smeared out across
hundreds or even thousands of nodes, it can provide data consistency across
the replicas (via Paxos, something that SimpleDB/Dynamo cannot provide and
pass back to the application layer for reconciliation) and it can do this
rather quickly.

That is a rather powerful component to make readily available to any Erlang
app. If you can't think of ten or twenty possible applications of this then
you are not trying hard enough.

------
DaniFong
It's worth mentioning here that Joe Armstrong developed Erlang for his thesis
work.

~~~
hassy
Not really. Erlang was born out of practical experiments in language design
with the explicit aim of finding a better way to program telephony
applications. The experiments were done over a few years in the second half of
80s at the Computer Science Laboratory at Ericsson.

Joe's PhD thesis which describes the design decisions and Erlang's philosophy
was published much later, at the end of 90s IIRC.

