Several technical contributions are emerging nowadays to fulfill the new requirements foreseen in the 5th generation (5G) of mobile communication systems. Among these contributions, different variants of waveform design are proposed for the new radio air interface as alternative to orthogonal frequency-division multiplexing (OFDM) adopted in 4G. However, in order to prove the feasibility and the benefits of the proposed waveforms, practical hardware implementations are necessary. This paper presents one of the first flexible and efficient hardware platform for waveform design proof-of-concept. The proposed platform constitutes a complete hardware/software development environment, with digital processing, radio frequency boards, and all associated interfaces for control, communication, and display. Promising waveform candidates are implemented, in addition to OFDM, with careful architectural choices to allow fair comparisons. Furthermore, the proposed platform allows the support of several communication scenarios as foreseen in 5G.