  While the use of formal verification techniques is well established in the
development of mission-critical software, it is still rare in the production of
most other kinds of software. We share our experience that a formal
verification tool such as Coq can be very useful and practical in the context
of off-the-shelf software development -- CAD in particular -- at least in some
occasions. The emphasis is on 3 main areas: factors that can enable the use of
Coq in an industrial context; some typical examples of tasks, where Coq can
offer an advantage; examples of issues to overcome - and some non-issues - when
integrating Coq in a standard development process.
