Broker for Algo Trading

[sawtooth500 33]

Anyone know of a commission free broker that has an API to do algo trading?

-Interactive Brokers free commission tier does not give you API access.
-I've used the DAS CMD API and am familiar with it - it works well. Problem is which broker can you use DAS with that it commission free? I just tried Charles Schwab because DAS just got support for Schwab - but Schwab advertises as commission free, and *technically* they are but they will sneakily charge you a .005/share exchange fee... so that adds up quickly. Doesn't matter if it's not technically commission going to Schwab, it's still money I'm getting charged so Schwab is a no-go.
-Tradestation I can personally verify IS actually commission free and does give you an API... but the problem with Tradestation is that if your algo relies on flipping positions (like mine does), tradestation does not let you flip in one transaction - for example, if you're short 100 shares, and want to flip to long 100, in DAS you can put in a single buy 200 order and it'll flip - in tradestation, you need to enter a cover 100 order OSO (order sends order) buy 100 order, meaning that once the first order is filled it automatically sends the next order. This takes like half a second extra and results in worse fills.
-I looked at alpaca.markets, did not personally try but reached out to them, and they adverstise commission free but I can't flip positions there like in DAS - they said they make you do a cover followed by buy order to flip

Another consideration is that I prefer to use DAS because with DAS I get a time and sales feed via the CMD API that I can use to run my algo on - other platforms like tradestation don't actually provide the market data I need to run the algo, so I need to tie in with a 3rd party provider like polygon.io for the real time market data and time and sales feed. Polygon.io is great actually, I have very positive things to say about them it's just another $200 monthly cost for their real time data which I'd rather get through DAS...

So anyone have any broker suggestions for trading via algo? Ideally commission free and they allow me to flip positions with a single order!