Kathleen Ting details 8 misconfigurations that can bring ZooKeeper down.
Kevin Lynagh provides the rationale behind visual interfaces, and presents a sample example written in ClojureScript.
Johan Oskarsson explains how Twitter is using Zipkin to trace a pages in order to see their execution path and to determine the time spent for loading for performance monitoring and analysis.
Jez Ng, CJ Carey and Jonny Leahey introduce Doppio, a JVM written in CoffeeScript for the browser.
José Valim introduces Elixir, a programming language for the Erlang VM – an attempt to provide better abstractions and productivity tools like protocols and macros usually required for web development.
Jeff Kelley introduces the Grand Central Dispatch framework for writing concurrent applications for iOS.
Jason Wolfe discusses Graph, a declarative approach for system composition, used by Prismatic to put together various components: in-memory caches, pub/sub messaging, indices, HTTP handlers, etc.
Daniel Spiewak discusses the question of whether or not the complexity class NP-time is fully defined by the complexity class P-time issue.
Håkan Råberg introduces Enumerable.java – an extension adding Lambdas to Java 5 – and shen.clj - used to compile Shen, a LISP variant, to Clojure.
Jamie Allen explains some of the terminology encountered by Scala developers and not only: OO features, pattern matching, functional programming, actors, futures, tuples, implicits, type theory, etc.