Experience Report: Scala usage at Capital IQ ClariFI

Paul Chiusano

About us

We make software for quantitative investment managementSell to asset managers, hedge funds, etcFlagship product, ClariFI

Portfolio optimizationModel/factor building, backtestingPerformance/risk attributionBuilding, simulating trading strategiesScreening, event studiesOverall data managementEtc...

Founded in 2000, acquired by Capital IQ (itself owned by S&P) in 2007Team size: 20 devs

Our first Scala project

About 2 yrs ago, needed to rewrite/redesign PA backendFP a natural fit for the domainScala the clear winner among JVM FP languages

Results highlights

Scala implementation about 1/3 the LOC, comparable memory usage and speed

More generic, modularNew code had much better testing

ScalaCheck a major winOn a few occasions, discovered bugs in old implementation

In production now for over a year

Since then

Used Scala on another major project, more on the wayScala well-suited for backend / analytics layer

Several other devs have now used Scala in some capacityActively hiring people with Scala/FP experience

Scala: the good

Scala/Java integrationBasic functional idiomsThe type systemOptional non-strict evaluation

Scala: the bad

IDE support (as of 2008)Scala generics vs Java genericsLimited, unpredictable type inferenceFunction values are monomorphicWeak standard library

More on our environment

Scala code in a separate project, exports a .jarTools: Eclipse, NetBeans, Ant, ScalaCheck + JUnit, SBinaryMore recently: Vim, sbt, Scalaz

How hard is Scala to learn?

Learning curve can be very gradualType system probably biggest stumbling block

Deep FP knowledge takes a long time to developRequires shift in mindset Hard to find people with deep experience

Other takeaways

Good design is hardRewrites not always bad

Any questions?

More info at my blog: pchiusano.blogspot.comAlso on twitter: @pchiusanoemail: paul.chiusano@gmail.comOur website: clarifi.com