The Twitter Engineering Blog

Information from Twitter's engineering team about our technology, tools and events.

Results from Engineering for: 2013

CocoaSPDY: SPDY for iOS / OS X

For over a year now, Twitter has supported the SPDY protocol and today it accounts for a significant percentage of our web traffic. SPDY aims to improve upon a number of HTTP’s shortcomings and one client segment in particular that has a lot of potential to benefit is mobile devices. Cellular networks still suffer from high latency, so reducing client-server roundtrips can have a pronounced impact on a user’s experience.


Forward Secrecy at Twitter

As part of our continuing effort to keep our users’ information as secure as possible, we’re happy to announce that we recently enabled forward secrecy for traffic on,, and On top of the usual confidentiality and integrity properties of HTTPS, forward secrecy adds a new property. If an adversary is currently recording all Twitter users’ encrypted traffic, and they later crack or steal Twitter’s private keys, they should not be able to use those keys to decrypt the recorded traffic.


Slave Recovery in Apache Mesos

Cross-posted from the Apache Mesos blog.

With the latest Mesos release, 0.14.1, we are bringing high availability to the slaves by introducing a new feature called Slave Recovery. In a nutshell, slave recovery enables:


Twitter University on YouTube

Here at Twitter, we embrace open source and support the ongoing education of our team, as well as the general public. The intersection of these domains is particularly important to us, and led to the establishment of Twitter University, which supports these efforts and helps make Twitter the best place in the world for engineers to work.


Netty 4 at Twitter: Reduced GC Overhead

At Twitter, Netty (@netty_project) is used in core places requiring networking functionality.

For example:


Summer of Code 2013 Results

For the second time, we had the opportunity to participate in the Google Summer of Code (GSoC) and we want to share news on the resulting open source activities. Unlike many GSoC participating organizations that focus on a single ecosystem, we have a variety of projects that span multiple programming languages and communities.

We worked on three projects with three amazing students over the summer.


Dremel made simple with Parquet

Columnar storage is a popular technique to optimize analytical workloads in parallel RDBMs. The performance and compression benefits for storing and processing large amounts of data are well documented in academic literature as well as several commercialanalyticaldatabases.


Observability at Twitter

As Twitter has moved from a monolithic to a distributed architecture, our scalability has increased dramatically.


Streaming MapReduce with Summingbird

Today we are open sourcing Summingbird on GitHub under the ALv2.


Improving accessibility of

Timelines are the core content of Twitter. And with device independence being one of the core principles of accessibility, we’ve spent the past quarter tuning and enhancing keyboard access for timelines. Our goal was to provide a first-class user experience for consuming and interacting with timelines using the keyboard.