Abstract-This paper describes the problem context of software development for mass-produced embedded systems, with distinguishing factors such as the co-design of software and hardware, strong focus on manufacturing aspects, supplier involvement and safety-critical functionality. In this context there is a need for a holistic model to explain the failures and successes industrial projects, where just investigating a single dimension, e.g. chosen ways-of-working or architecture is not sufficient.The main contribution is a holistic model consisting of five archetypical approaches to embedded software development, based on a mapping study over industrial cases in literature. The approaches range from "traditional" stage-gate projects focusing on product qualities and large integration efforts, to fast development in short loops by autonomous teams based on a composable software platform. The model aligns the processes with the architecture of the embedded software, and the implications on the business and the organisation. The model allows an research & development(R&D) organisation to identify where it is positioned and to evolve its software development approach. The model is elucidated by two empirical cases from a Swedish company.