For metaproteomic analyses in microbiome research, a commonly used technique is the data-dependent acquisition (DDA) mass spectrometry. A key limitation of this method is that multiple repeated runs are required for each sample to obtain a stable set of detected peptides. Technically that is mainly because of undersampling and that the MS/MS spectra are taken outside the elution peak. More recently data-independent acquisition (DIA) methods have been successfully proposed to overcome some of the limitations, but there remains a lack of free and easy-to-use software for the analysis of DIA mass spectrometry proteomics. This is especially true in the context of metaproteomics, which proposes additional requirements for the software. To this end, we have developed a free and open-source software package for analyzing complex DIA metaproteomic data. It enables accurate and consistent quantification and we demonstrate its feasibility in gut microbiota metaproteomics using laboratory assembled microbial mixtures as well as human fecal samples.