SLHAplus: a library for implementing extensions of the standard model

We provide a library to facilitate the implementation of new models in codes such as matrix element and event generators or codes for computing dark matter observables. The library contains a SLHA reader routine as well as diagonalisation routines. This library is available in CalcHEP and micrOMEGAs. The implementation of models based on this library is supported by LanHEP and FeynRules.