The WaveDAQ is a full custom, compact and highly integrated trigger and data acquisition system. Despite the decisive urge from the MEG II experiment at PSI aiming at a sensitivity of 6×10⁻¹⁴ on the μ → eγ decay, it is a general purpose device suited for small and medium-sized applications in the range from 16 to about 10 000 channels. It exploits the performance of the DRS4 waveform digitiser with a sampling speed programmable from 1 to 5 GSPS; each input channel can supply HV to arrays of SiPMs and provides a front-end amplification with gains chain in the range from 0.5 up to 100 and GHz bandwidth. Input signals are, in parallel to the DRS4, digitised at 80 MSPS and used in an FPGA-based trigger; fast discriminators associated to each input channel are also used for online reconstruction. This paper presents the WaveDAQ design principles and the results obtained by a demonstrator in the MEG II pre-engineering run in fall 2017 with a homogeneous LXe detector and a plastic scintillation detector both readout by SiPMs and in the tests associated to the ΔE-TOF prototype of the FOOT detector.