Since the introduction of SPICE non-linear controlled voltage and current sources, they have become a central feature in the interactive development of behavioural device models and circuit macromodels. The current generation of SPICE-based open source general public license circuit simulators, including Qucs, Ngspice and Xyce (c), implements a range of mathematical operators and functions for modelling physical phenomena and system performance. The Qucs equation-defined device is an extension of the SPICE style non-linear B type controlled source which adds dynamic charge properties to behavioural sources, allowing for example, voltage and current dependent capacitance to be easily modelled. Following, the standardization of Verilog-A, it has become a preferred hardware description language where analogue models are written in a netlist format combined with more general computer programming features for sequencing and controlling model operation. In traditional circuit simulation, the generation of a Verilog-A model from a schematic, with embedded non-linear behavioural sources, is not automatic but is normally undertaken manually. This paper introduces a new approach to the generation of Verilog-A compact device models from Qucs circuit schematics using a purpose built analogue module synthesizer. To illustrate the properties and use of the Qucs Verilog-A module synthesiser, the text includes a number of semiconductor device modelling examples and in some cases compares their simulation performance with conventional behavioural device models. Copyright (c) 2016 John Wiley & Sons, Ltd.