There is an alternative for some processing chains like coherence estimation and calibration implemented utilizing GPUs - https://bitbucket.org/cgi-ee-space/alus/src/main/
In ‘Downloads’ section pre-compiled binaries are available for download.
More processors will be added during specific projects.
For Sentinel-1 majority of the logic and algorithm’s has been ported from SNAP. Due to silicon differences and some various tile handling mechanisms, there could be some differences with SNAP results, but overall it should be one to one match for analyzing.
Feedback is strongly encouraged.