I thought it would be an interesting project to write my own bid-based voting bot software similar to the "drotto" software that most existing bid-based voting bots use today. I don't know Ruby so I instead decided to build it in JavaScript using the Steem JS library.
So I coded up the basic features today and put it up at https://github.com/MattyIce/postpromoter and have also delegated 8,000 SP to the 
Naturally it's also been added to the Steem Bot Tracker website so you can bid responsibly!
The features are currently very basic, but I plan to add more over time - or maybe someone else here can also contribute! Additionally I plan to write some tutorial posts that walk through the code so others can learn how to build similar projects on Steem!
Existing Features
- Min and max SBD bid amounts
- Option for enabling / disabling bids on comments
- Ability to set a template the bot will use to comment on posts it upvotes
Future Features (To-Do List)
- Support different bid window lengths
- Automatically refund invalid bids
- Blacklist to block spammer accounts
- Disabled mode which automatically refunds all bids
- Admin panel website to adjust settings and monitor status / bid windows
- User-facing website showing details about the bot
Posted on Utopian.io - Rewarding Open Source Contributors