Distributed Decentralised App Substrate
Pi is a software platform for the rapid development and deployment of massively scalable and resilient infrastructure software services. It was the result of strategic ambitions of a major telco to explore new, game-changing ways of delivering combined software, infrastructure and network services in the cloud.
The Pi software - the focus of this site - was a major piece of a bigger, holistic puzzle, the heart of a 'cloud operating system' running atop containerised data centre hardware, connected by software driven networks. Started by a small core group spanning software, systems, network and infrastructure architecture and engineering, over two years the entire effort evolved from the initial exploration phase to deliver the full hardware and software stack, offering a fully-featured, Amazon EC2 and S3 compatible set of compute and storage services across many hundreds of machines and three geographic locations.
By early 2011, Pi was in regular and rapidly growing use across the organisation, transforming the server provisioning and management lifecycle, in turn fuelling a fundamental shift in what small, lean teams could accomplish, rapidly and cheaply. It had just officially become the Most Innovative Software Product company-wide, largely on the back of unsolicited nominations and praise from its growing user base. It was drawing favourable comparisons from technology leaders acquainted with the IaaS startup landscape at the time.
Over the next few months, the tide turned as strategic realignment and organisational seismics put a stop to the development effort in favour of a commitment to the more traditional and less ambitious vendor path. Although Pi has remained in use through 2013, it is very much on life support.
The Pi codebase was open-sourced in 2012 in an effort to extend its lifespan. However without a large pool of machines to control, and with the evolution of alternatives such as OpenStack and CloudStack, it has lacked a sufficiently captivating end goal to motivate further active development and evolution.
This site presents the entire open-sourced Pi codebase, a description of the design of the Pi software stack, and a summary of the challenges and learnings derived in the course of developing the platform.
Its aim is to capture and preserve the experience from successfully meeting a demanding set of infrequently encountered design goals, and thus encourage further contributions.