Can I cast from outside the official mac/iOS farcaster clients?

Rust, Distributed Systems | Hangout here on Farcaster from time to time 

yea you can. 
https://github.com/standard-crypto/farcaster-js js library written for it that allows you to cast.

im working on a rust lib for farcaster, currently has read-only functionallity, working on getting jwt's & posting working (have to rewrite some custom stuff from did-jwt)

aspiring shrimp farmer ~ eng @ bloom (yc s21)

https://farcasterxyz.notion.site/Farcaster-ecosystem-af207db2885349d383dee69eccd77b37

heres the ecosystem page to poke around & look at different projects/libs