Of course, not everyone welcomes the flexibility Git provides. Some see this freedom enabling confusion. Proponents counter that you're not required to use all of Git's power, but it's there to help out when the project requires more than a central government. Some developers have create Repo to combat the complexity of Git. A tool for pushing changes through multiple repositories, Repo is, in a way, the re-emergence of central control for the Git ecosystem.
Open source programming tool on the rise: Gerrit
The rise of code reviews at larger development shops could lead to only one thing: the creation of a tool to automate the process. Enter Gerrit.
Meant to work closely with Git and Repo, Gerrit allows code validators to send comments to the central Git repository, creating an extensive meta layer of discussion on top of the code itself. In the old days, discussions took place in header comments, but by separating comments to a dedicated layer, Gerrit allows for a more sophisticated discussion that doesn't force future readers to wade through old change discussions before getting to the code.
Open source programming tool on the rise: Hadoop
The power of Hadoop was put publicly on display in the form of Watson, IBM's "DeepQA" machine that recently beat the two greatest human champions in a game of "Jeopardy." The framework was used to orchestrate dozens of algorithms searching for an answer in parallel.
Hadoop is a general tool kit for splitting apart the work into pieces that can be computed on separate servers, then joined together into a final product. Google pioneered the idea when it needed to choreograph a vast army of servers to crawl the Web, and now Hadoop offers a general framework that's being used again and again in similar situtations.
Hadoop's original simple core may be several years old now, but there's a great deal of interest in spinoffs that bundle Hadoop with code for tackling specific problems. Mahout, for one, is a scalable machine-learning framework that analyzes large data sets for patterns that might emerge. Hive offers a data warehouse that can be queried with parallel search using HiveQL. This method is fast becoming a popular approach for dealing with massive quantities of Web logs.
Open source programming tool on the rise: jQuery
These plug-ins are usually pretty easy to string together and glue into a coherent display. There are even some bigger collections of plug-ins that harmonize the widgets. jQuery Mobile, for instance, is dedicated to producing applications that run well on the small screens of smartphones.