The document discusses KPN's use of Beaker and VMpooler for multi-platform testing of Puppet modules. It outlines the requirements for an automated testing pipeline that runs syntax, unit, and acceptance tests on Linux and Windows platforms in parallel. The solution involved setting up a Jenkins master and build slaves along with VMpooler to provision VMs for testing. Beaker is used to run acceptance tests across multiple platforms. Details are provided on configuring the testing components and writing acceptance tests. Metrics on modules, test types, runs, and failed tests are presented.