“…Testing is yet another aspect that seriously limits the adoption of agile methods in the safety critical context, since incorporating verification techniques is challenging, and these activities are work intensive (Paige et al, 2008). Indeed, while test-driven development is widely used in the agile community (Nerur et al, 2005), in safety-critical software development, instead, testing is done only in the final phases (McCaffery et al, 2016). Moreover, some standards, such as the CENELEC EN50128 (Comité européen de normalisation en électronique et en électrotechnique, 2011), mandate that the testers must be responsible for specifying the test and that developers and testers must be separate persons (Jonsson et al, 2012).…”