2011 - The year that was

The very first thing that strikes me as I start writing a personal account of 2011 as it was is how it has successfully infused some of the transformations in my regular chores of programming world. It has been different and I am starting to enjoy some of the renewed vigor in areas like Type Systems, Machine Learning, Algebra etc. Throughout the year I used mostly one single language - Scala for programming with some occasional stints in Haskell and Octave for the Stanford Machine Learning course. But I have no regrets in not being more polyglotic, because I could find more time to dig deep into some of the more fundamental areas like algebra, category theory and type systems.

Favorite books read / started reading

• Types and Programming Languages by Benjamin Pierce : definitely a Knuth statured book in the theory of type systems in programming languages. It's written with a very pragmatic outlook and contains all necessary implementation details to complement the accompanying theory. I have not yet finished reading the book. I am into Chapter 20 and 21 doing recursive types, that look to be one of the most exhaustive treatments of the subject I have ever seen. If and when I manage to finish reading this book, my next plan for theory of programming languages is Design Concepts in Programming Languages.
• Conceptual Mathematics by F. William Lawvere and Stephen H. Schanuel - I started reading this book from recommendation by Paul Snively as a precursor to Benjamin Pierce's Category Theory for Computer Scientists. This is an excellent introduction to Category Theory and contains a detailed treatment of the unifying ideas of mathemetics, set theory and category theory.
• Learn You a Haskell for Great Good by Miran Lipovaca - possibly the most recommended and updated Haskell reading in print form. The chapters on Applicative Functors, Monads and Zippers are real treats.
• Language Proof and Logic by Jon Barwise and John Etchemendy - Starts with a great review of logic and goes on to discuss proofs of soundness and
• A Tribute to a Mathemagician by Cipra, Demaine, Demaine and Rodgers - Another book in a series written by those illustrious mathematicians and puzzlers who were inspired by Martin Gardner. It's a fascinating collection of essays on mathematical puzzles - get it if you have that bent of mind.

Exploring new ideas

• Category Theory - Often debated on its usefulness in the practical world, category theory gives you the basic understanding of programming language design, semantics and domain theory. I did lots of readings on Category Theory this year and this has led to a more concrete understanding of type systems as well. Hope to continue more in 2012.
• Algebra - What's the algebra behind the term Algebraic Data Types ? I took some notes as I started understanding the algebra of recursive data types. Have a look at my notes on github.
• Machine Learning - I took the Stanford online course on machine learning. It's been a revelation for me to find the pervasiveness of the subject in today's application context. Also the course encouraged me to look more into mathematics that govern all the theories that ML implements.

Some great papers read

• Theorems for Free! by Philip Wadler
• Monad Transformers and Modular Interpreters by Sheng Liang, Paul Hudak and Mark Jones
• Lazy Functional State Threads by John Launchbury and Simon Peyton Jones
• A Domain-Specific Language for manipulation of binary data in Dylan by Hannes Mehnert and Andreas Bogk
• RRB-Trees: Efficient Immutable Vectors by Phil Bagwell and Tiark Rompf
• Categorical Programming with Inductive and Coinductive Types by Varmo Vene
• Functional Programming with Overloading and Higher-Order Polymorphism by Mark P Jones

Programming and Open Source

Once again a year passed by where I did 95% of programming in Scala. Scala has somehow hit the sweet spot of my liking - OO, FP, JVM, succinctness, I get them all in Scala. However, having said that I have every honest intention to renew all my friendships with Haskell and Clojure in 2012. I did quite a bit of Haskell in 2010 and still reaping the ebnefits of being a better Scala programmer piggybacking on my Haskell thoughts. I know Haskell is purer, a piece of Haskell code can be poetry. But the pragmatics of being on the JVM makes Scala more appealing to my professional life.

Two of my open source projects sjson and scala-redis are still quite active. I get pull requests on a regular basis and of course quite a few feature requests and bugs reported on Github. I plan to make some major upgrades to sjson particularly when reflection becomes more accessible in Scala 2.10. Also in line are some enhancements planned towards functor based JSON composition in sjson, which I plan to take up pretty soon. I tried to upgrade scala-redis to keep it in sync with the various releases of redis. Thanks to all of you for trying out sjson and scala-redis. Open source programming is fun and I consider myself blessed to have the opportunities to give something back to the community, which has given me so much over the years.

Any mention of my programming activities in 2011 would be incomplete without mentioning scalaz. I now use it in almost every project. It's really a great creation by Tony, Runar, Jason, Paul and the other members of the team. Using scalaz, I have learnt a lot about functional programming and functional thinking.

Another library that I have been using regularly since its inception is Akka. Asynchronous messaging is the gateway towards writing scalable applications and Akka provides the right set of batteries towards that. You get messaging, data flows, agents, STMs and all through a nice set of APIs both in Java and Scala. I think Akka is nicely poised to be the killer application to push Scala into the mainstream.

Some Publications

In 2011 I got the following two papers published, one of them as part of the esteemed team of Justin, Kresten and Steve. Thanks guys ..

• Debasish Ghosh, Justin Sheehy, Kresten Krab Thorup and Steve Vinoski, "Programming Language Impact on the Development of Distributed Systems," FOME'11: Future of Middleware at Middleware'2011.
• Debasish Ghosh, "DSL for the Uninitiated," Communications of the ACM, vol. 54, no. 7, pp. 44-50, July 2011

Some nice experiences

I attended 2 international conferences in 2011 - QCon London and PhillyETE. I also talked at PhillyETE on Domain Specific Languages. Both the conferences were amazing and I got to know in person many of the faces that I see and talk to regularly on Twitter and Google+. Incidentally I will also be talking at PhillyETE 2012 slated to be held in April.

My book DSLs In Action came out in late Dec 2010. 2011 was the year where I got the first royalty check from Manning. The writing of the book has been an amazing experience and to get to hear good words from people using the book gives another level of satisfaction. Thank you Manning for giving me the opportunity.

Looking forward to 2012

I am not one for resolutions, but here's a wish list towards more geekery in 2012 ..

• Program more in Haskell and Clojure
• Blog more (It was pathetic in 2011)
• Do more math
• Attend more online classes (currently registered for Natural Language Processing, Algorithms and Probabilistic Graphical Modeling at Stanford)
• Try to do more conferences (currently registered for PhillyETE and Scala Days)
• Learn more algebra, type theory and category theory
• Get started with TAOCP Vol 4A
• Learn Factor

Wish you a very happy new year. See you all in 2012!