You may have heard the acronym SOLID. It is one of the most widely-referenced sets of software design principles, appearing everywhere from architecture guidelines to job descriptions. It's also closely associated with the Object-Oriented Programming (OOP) paradigm. This talk builds a critique of OOP through an exploration of the SOLID design principles. You may be thinking something along the lines of "overengineering" or "unnecessary complexity". But this talk makes a different point: that the simple, maintainable software engendered by SOLID principles may be best achieved by thinking outside of OOP.