Posts from April 2015

Open Location Code: Addresses for everything, everywhere

Thursday, April 30, 2015

Accurate street addresses are taken for granted in much of the world. But in many areas, formal street names and addresses don't exist and the only real alternative is to use addresses of the form "behind the old bus stop". Without a street address, it's difficult to organise deliveries, to receive visitors or to find businesses. And street addresses only work where there are named and numbered streets - without these, there's no easy way to provide someone with a location.

Area with unknown street names in Indonesia. (Google Maps)

Latitude and longitude coordinates can specify any location, but they’re long and cumbersome. What if they were more human-friendly, like a very accurate postcode that refers to just your home? We’re happy to share Open Location Code, a stand-alone open source library for this purpose.
The Open Location Code system allows people to derive plus codes from latitude and longitude coordinates that already exist everywhere. Plus codes are similar in length to a telephone number -- 849VCWC8+R9, for example -- but can often be shortened to only four or six digits when combined with a locality (CWC8+R9, Mountain View).  Locations close to each other have similar codes. They can be encoded or decoded offline, and the character set was chosen to avoid spelling words in more than 30 different languages. We removed similar looking characters to reduce confusion and errors, and because they aren't case-sensitive, they can be easily exchanged over the phone.

World's largest carrot,
H3+XG Ohakune, New Zealand.
The big gumboot.
GV+8J Taihape, New Zealand.

Developers of websites that need location from users (such as delivery or taxi firms in locations where street addresses are poorly defined) could use plus codes to get accurate locations from their users. Other services which map locations that don't have street addresses (such as water sources, mountain refuges, or nesting sites) could use plus codes since they don't rely on street information.

The big trout.
2W+GW Gore, New Zealand.
Kime Hut, in New Zealand's Tararua Ranges.

We have a sample implementation to find and use codes at You can download the latest release of the library from our GitHub page and join our discussion list to learn more.

by Doug Rinckes, Travel team

Students announced for Google Summer of Code 2015

Monday, April 27, 2015


Congratulations to the 1,051 students accepted for our 2015 Google Summer of Code! It was tough for the 137 mentoring organizations to choose from the huge number of applications we received - 6,409 proposals from 4,425 students - and we want to thank everyone who applied.

Accepted students will now enter the community bonding period where they will get to know their mentors and prepare for the program by reading documentation, hanging out in their IRC channel and familiarizing themselves with their new community before beginning their actual coding in May.

If you are interested in learning more about the 137 organizations that the students will be working with during the summer or reviewing important dates, please visit the program website.

We look forward to an exciting and productive summer of coding.

By Carol Smith, Open Source Programs Office

New projects in GSoC 2015

Thursday, April 23, 2015


As the summer draws near, we’re getting ready to announce the students accepted into Google Summer of Code (GSoC) 2015. With guidance from mentors, those students will spend their summer coding for one of the 137 open source projects that are participating this year.

This is the 11th summer we’ve run the program and many of the projects have been part of GSoC in the past, but we also have 30 projects which are making their GSoC debut this year. Welcome to GSoC, we’re looking forward to seeing the students’ contributions to your work!

  • Africa Soil Information Service
  • Bika Open Source LIMS Collective
  • Boston University / XIA
  • CentOS Project
  • CloudCV
  • Department of Biomedical Informatics, Stony Brook University
  • Foundation for Learning Equality
  • GitHub
  • Global Alliance for Genomics & Health
  • Google Kubernetes
  • HPCC Systems
  • Liquid Galaxy Project, Interactive Spaces
  • IP-over-P2P Project
  • JdeRobot - Universidad Rey Juan Carlos
  • jQuery Foundation
  • lowRISC
  • MBDyn, Department of Aerospace Engineering at the Polytechnic University of Milan
  • MinnowBoard Project
  • NumFOCUS
  • OncoBlocks
  • Pencil Code Foundation
  • Portable Native Client
  • Red Hen Lab
  • RIOT
  • Rspamd spam filtering system
  • Saros
  • Sustainable Computing Research Group ( SCoRe )
  • University of Nebraska - Helikar Lab

You can learn more about all of this year’s participating organizations at the program website. Students, check back on Monday, April 27th to see if your application has been accepted.

by Ashleigh Rentz, Open Source Programs Office

Jsonnet: a more elegant language for composing JSON

Monday, April 20, 2015

A few months ago, we quietly released Jsonnet: a simple yet rich configuration language (i.e., a programming language for specifying data). Many systems can be configured with JSON, but writing it by hand is troublesome. Jsonnet is packed with useful data-specification features that expand into JSON for other systems to act upon. Below is a trivial example of such expansion:

// Jsonnet Example
   person1: {
       name: "Alice",
       welcome: "Hello " + + "!",
   person2: self.person1 { name: "Bob" },
  "person1": {
     "name": "Alice",
     "welcome": "Hello Alice!"
  "person2": {
     "name": "Bob",
     "welcome": "Hello Bob!"
Jsonnet doesn’t just generate JSON: Jsonnet is also an extension of JSON. By adding new constructs between the gaps of existing JSON syntax, Jsonnet adds useful features without breaking backwards compatibility. Any valid JSON is also a valid Jsonnet program that simply emits that JSON unchanged, and existing systems that consume JSON (or its cousin YAML) can be easily modified to accept data in the full Jsonnet language. As such, Jsonnet is an example of a templating language, but one specifically designed for JSON data and less error-prone than other techniques.
“Jsonnet” is a portmanteau of JSON and sonnet. We chose that name to convey that data expressed in Jsonnet is easier to write and maintain because it is more elegant and concise, like a poem. This is not just due to syntactic niceties like comments and permissive quotes/commas, but because Jsonnet has all the modern multi-paradigm programming language conveniences needed to manage complexity. One key benefit is the ability to use Jsonnet's mixin and import features to write modular configuration template libraries, allowing the creation of domain-specific configuration languages for particular applications.
Most configuration languages are created ad-hoc for the needs of a given application, accruing features over time and becoming unwieldy. From day one, Jsonnet was designed as a coherent programming language, benefitting from both academic techniques and our experience implementing production languages. Unlike most configuration languages, Jsonnet has a full operational semantics, ensuring matching behavior from third party implementations as well as mathematical analysis. It is a very small and carefully chosen extension to JSON that can express both object-oriented and declarative styles. More importantly, unlike regular programming languages, Jsonnet is hermetic:  Its evaluation is independent of any implicit environmental factors, ensuring that high level configuration will resolve to the same thing every time.
Jsonnet is open source. It’s currently available as a library with C and Python bindings, and also as a command line utility. A real-world example configuration can be found on the website, where 217 lines (9.7kB) of Jsonnet expand into 740 lines (25kB) of configuration for other tools. Learn more about Jsonnet by reading the tutorial and experimenting with our javascript demo!

by Dave Cunningham, New York Technical Infrastructure team

Student ambassadors bring GSoC 2015 to more African students

Thursday, April 16, 2015

Student applications for Google Summer of Code (GSoC) 2015 closed on March 27th and this year’s mentoring organizations are now busy reviewing student proposals. While we await the results of that process, we’ve been looking at some of the early statistics for this year’s program.

One thing we’re very excited to see is that we received nearly four times as many student applications from Sub-Saharan Africa compared to last year! The gain primarily came from four countries: Cameroon, Kenya, Nigeria, and Uganda. These countries combined had just 45 students apply in 2014, but that number jumped up to 183 this year. Why was the increase concentrated in these locations? There’s a common thread that seems to be responsible: they are places where students active in the Google Student Ambassador (GSA) program organized local GSoC meet-up events.


After lending a hand to a fellow student organizing a meetup in December, GSA Tekang Check brought 77 students together in March at the University of Buea to learn about GSoC and help students apply. Participants from past years shared their experiences and encouraged attendees to submit proposals for projects they felt passionate about.


GSA John Muchiri welcomed over 100 students from St Paul’s University to a GSoC meet-up. The speakers talked about the characteristics good programmers develop and encouraged students to challenge themselves by applying to the program.

At Jomo Kenyatta University of Agriculture and Technology, GSAs Isaac Jumba and Dickson Marienga introduced students to GSoC as part of the local DevFest event which drew over 150 attendees. The session gave an overview of GSoC and encouraged students to sign up for a regional GSoC enthusiasts mailing list.


GSAs Ilo Calistus, Okwara Godswill, and Mgbemena Chike collaborated on a pair of events at the University of Nigeria in Nsukka. The first introduced students to the basics of programming for Android while the second taught students about using Git. Both events also introduced students to the world of open source and encouraged them to take part in GSoC.

At Ekiti State University, GSAs Sadiq Mary Oiza and Alabea Dare Micheal organized a GSoC meet-up for 35 students. After a discussion about current events at the university, the presenters gave an overview of the GSoC program and encouraged students to create profiles on the program website.

GSA James Uzoma organized a meet-up at the Federal University of Agriculture, Abeokuta where 40 students from 6 colleges enjoyed a series of talks featuring stories from fellow Nigerians who had participated in past years, an explanation of the requirements for participating, and some details about the different open source organizations students could apply to work with.


GSA Kagimu Brian brought together 72 students for a GSoC meet-up at Mbarara University of Science and Technology. Attendees learned about the benefits and experiences that can come from taking part in GSoC, along with an introduction to Git.

Only a limited number of students can be accepted in GSoC each year, but we hope to welcome several of the students who attended these events into this year’s program. Accepted students will be notified via email by 19:00 UTC on April 27th, so keep watching your inbox.

By Ashleigh Rentz, Open Source team

UIforETW: Windows Profiling Made Easier

Tuesday, April 14, 2015

Microsoft’s Event Tracing for Windows (ETW, aka xperf) is an amazing tool for understanding the performance of Windows computers. ETW offers an incredibly deep view into the entire system and allows investigations of complex problems that would otherwise be intractable. It can even be used to record traces on a customer’s machine for later analysis on a developer’s machine, to investigate performance problems that cannot be reproduced locally.

However, the process of recording ETW trace has always been challenging, so we’re pleased to share a new tool we’ve been developing:  UIforETW. This tool brings point-and-click simplicity to recording ETW traces, works around several trace recording bugs, and is a handy dashboard for managing and annotating traces. And since UIforETW is open source, you can add additional features for your own particular needs.

Tracing can be done to a file or to an in-memory circular buffer. Trace compression, high-speed sampling, heap tracing, and other options can be configured with the click of a button. UIforETW lists the recorded traces and lets users rename and annotate them. When you want to analyze a trace, you can launch Microsoft’s trace viewers from UIforETW, and UIforETW will configure improved viewer defaults for WPA.

UIforETW was written by a Chrome developer, so it has a few Chrome specific features. If the Chrome symbol server is enabled, then UIforETW downloads and strips the Chrome symbols in order to avoid a twenty five minute delay when WPA loads the symbols. UIforETW also preprocesses the traces in order to categorize the Chrome processes by type. These features can be turned off in the Settings dialog if you aren’t working on Chrome. While the Chrome specific features will not be needed by most developers, they demonstrate the potential value from custom processing of traces.

UIforETW is a new project but is already being used for production work. More technical details and information about UIforETW and ETW in general can be found in the author's blog post and discussions can be had at our discussion group. Information about contributing to UIforETW can be found in the CONTRIBUTING file in the GitHub repo.

by Bruce Dawson, Chrome team