One important component of Themyscira Wireless system sw, specifically
themwi-mgw, implements speech transcoding between GSM codecs on the inside and
G.711 on the outside.  This essential function creates a dependency on some
specialized libraries that implement the codecs which need to be supported.
The following codec libraries are currently required:

1) libgsm, the original GSM 06.10 implementation from 1990s;

2) gsm-codec-lib developed by Mother Mychaela:

https://www.freecalypso.org/hg/gsm-codec-lib/

This gsm-codec-lib collection provides two libraries; as of this writing, one
is already implemented while the other is in the plans:

2a) libgsmfrp is the Rx DTX handler for the original FR codec, a front-end
    preprocessor that sits in front of libgsm decoder.  This preprocessor
    implements functions specified in GSM 06.11, 06.12 and 06.13, and these
    functions are required (not optional) for a network-side implementation of
    GSM FR codec in a TRAU-like component.

2b) libgsmefr will be a librified (turned into a library) version of the
    official reference implementation (from ETSI) of GSM EFR codec.