There are a number of different skill sets that have been shown to be important when hiring and retaining top quality freelance C++ developers.
Knowledge of object-oriented programming techniques and design patterns
Understanding of software design principles and techniques such as abstraction, encapsulation, information hiding, polymorphism, inheritance, etc.
Familiarity with different versions of C++ (e.g., ISO/ANSI C++ Standard) and GNU tools used by developers at your organisation (e.g., clang).
Useful skills include: C++ development using Visual Studio or Eclipse; Linux or other Unix shell scripting; Git version control system; SQL or NoSQL database knowledge; experience with source code management system such as Subversion or Git; experience with build systems such as Make or MSBuild.
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