Build system

Description

The OLPC XO software build system has the requirement of combining software from various sources:

• A specific set of packages from Fedora Linux
• Some OLPC-specific packages which are not available in Fedora
• Some OLPC-forked packages where the versions in Fedora do not suit our needs exactly
• Sugar activities
• OLPC-specific configuration

The build system outputs software images which can be flashed to XOs for testing and deployment.

While OLPC produces generic software images, almost all deployments will want to add some level of customization (specific Sugar activities and software applications, default settings, etc). To allow for this, the build system can be easily installed and used by deployments and developers, allowing for easy local customisation.

Current build system

OS Builder is used for current and upcoming OLPC software releases. Compared to its predecessors, it makes extensive use of Fedora's build tools under a higher layer which allows for organisation of components and easy customization. It is also easier to install and use.

Historical build systems and their evolution

Pilgrim was the first build system, developed by OLPC and Red Hat, and used for OLPC's early software releases.

Puritan was developed after pilgrim started to show signs of outgrowing its design, calling for a cleaner and leaner system. However, it was never adopted officially by OLPC.

Image builder was developed as a post-processing tool to complement Pilgrim when OLPC decided to hand off part of the image customization process to deployments; it takes Pilgrim images and applies various customizations to them to produce a new output image. This started to outgrow its design when various parts of pilgrim needed to be copied into Image builder in order to be able to make more invasive customizations.

For initial software development for the XO-1.5 laptop, a desire to move to standard Fedora build tools emerged. fedora-xo was used to produce the first XO-1.5 software release, but the resultant build system was messy and left no systematic process for customizations by deployments. This lead to design goals for future build systems to balance use of Fedora build tools, organisation of OLPC's special requirements, and the ability for deployments to easily obtain and use the tool while making customizations to the image.

School Server Build Tools

See XS Building Software for details.