Mastodon <-> Twitter cross-poster.
Requirements: Python 3.4 minimum, with two packages, python-twitter version 3.2 upwards and Mastodon.py version 1.0.2 upwards:
# Python 3
pip3 install -r requirements.txt
For basic usage, just run the MastodonToTwitter.py script and follow the on-screen prompts. To change the polling interval or the instance of Mastodon the script talks to, edit the settings in the script.
The script stores your credentials in a bunch of files ending on .secret. The contents of these files let people access your twitter and Mastodon accounts, so do not share them around.