As a crucial suggestion, and feature request, and I speak for many, PLEASE allow us to purchase fractional shares in the short position.
And PLEASE allow us to set limit orders for fractional shares, in order to move our stop loss up and lock in profits, or set a take profit and walk away from the screen on these fractional share orders.
Please get my request in front of your engineer’s prudent eyes. 
@Veng34nc3Th3k1dd Definitely, there is an active project to allow limit orders for fractional shares. Shorting fractional shares, however is a bit problematic and may be awhile. The initial issue is that shares are borrowed in blocks of 100. If an individual client wanted to short, for example, .5 shares, Alpaca would need to borrow 100 shares. Alpaca would then hold (in broker inventory) 99.5 shares. Alpaca would then be required to pay the borrow and other fees (eg dividends) on those shares. It would be cost prohibitive to allocate all those costs to the client (eg borrow fees for 100 shares when only shorting .5 share), but it’s also cost prohibitive for Alpaca to absorb those fees too.
So happy to hear allowing limit orders on fractional shares are an active project. It would make us so happy to be able to move a stop loss up, lock in some profits, and not have to miss any orders and have to rely on alerts and manual trading.
I understand. There must be some solution? Maybe we can brainstorm. IBKR is able to. I wonder how they’re doing it. Maybe you can charge everyone a margin they must hold in order to short or something? I’m sure major assets there will be many buyers at one time. So, the 100 shares can be split between all active orders at a time, creating an “Available shares” amount to be shorted amongst everyone. I believe this is how IBKR does it.