If you are not able to pay market rates (that match the big tech companies) this is the markets way of saying "you should be denied access to this talent because it can be better utilized elsewhere"
Pay up or go away, stop trying to find the secret to underpaying devs.
How much equity are you keeping? Probably a greedy amount.
So many startups fail because they cant find devs while the founders are trying to keep a Zuck like share of the company based on some 10 year old Fred Wilson blog post.