I cannot refrain from some advertising of my own raw developer 
Photoflow allows to open most of the old and recent RAW images, apply some of the state-of-the-art demosaicing algorithms (Amaze, LMMSE, IGV and now also RCD), bypass color management by outputting the demosaiced data in the camera color profile (which is then embedded in the output file for a correct and consistent workflow if further processing is needed), apply lens corrections directly after the demosaicing phase, and finally save 32f TIFFs than can be opened in GIMP or other image processors.
All what @RawConvert has described, in one single step…