Chumbi - I am the sole author of Chumbi, a package of unit generators for ChucK. This package provides multi-channel ambisonic excursions for ChucK users. Formally, it offers ambisonics in up to the fifth order, but can be user-compiled for higher orders. It's API can be found here.
Encode.chug & Decode.chug - ChucK Chugins that act as ambisonic encoders and decoders, up to 5th order. This is the source code for Chumbi.