The language has gotten to a pretty nice place, but the ecosystem is nowhere near caught up. A lot of APIs still haven&#x27;t even incorporated the idiom of passing const references, almost exclusively taking pointers to non-const and defining their own idiosyncratic ownership schemes. Qt4 is a good example: RAII of widgets is hazardous because windows&#x2F;containers will delete their &quot;children&quot; (i.e. things that are under them in the widget hierarchy, not members), even if they&#x27;re on the stack. This means that simply declaring local variables in the wrong order can cause a double delete. I encountered this in tutorial code on the Qt site, which kind of put me off choosing Qt for new projects.