Not to be offensive, but you're brainwashed. You should be thinking about yourself. Why are you sacrificing your career, happiness, quality of life, and opportunities to a company that sounds like they're using/abusing you--low pay, no equity, bad work environment.
If they're so dependent on you, then you should be compensated accordingly. Your value to the company and your pay are directly related.
I'm too cynical about this - get your issues on the table, and either get something (more money, bonus/profit-sharing, equity) or get out.
I think these guys are making a mistake, though, because they're not just letting you get by making a little less that what you could make on the open market, and they're not just giving you a small amount of equity when you could perhaps demand more. They're playing with fire, because there's a good chance you could go out and find a good job, and by the time they find out you're dissatisfied, it's too late.
But here's what I'm certain of: If, as other commenters have recommended, you have a meetup with them, and you let them know that you feel you're not being adequately compensated, and you've been thinking of starting a job hunt, but that your sense of loyalty dictates that you let them know now, before to get fed up and before you find another job, they'll give you a sweeter deal.
They may not be able to afford to pay you more cash, but they can definitely afford to give you a decent equity stake. I can't say how much would be okay, but 0% is definitely not okay. In this case, you need to turn the tables. Once you've agreed to work for equity in lieu of a full-market salary, you become an investor, and they need to pitch you on the company's future. As for deciding what's appropriate, I'd recommend not thinking in terms of a percent, but have them make the case for the company being worth X amount. If they've raised money from other investors, then that may already be determined. Then you can agree on an amount of equity that's equal to a certain amount of the company's value. If you think you've missed out on $50,000 of compensation so far, then you should ask for that much equity, plus whatever extra you think you should get for the work you'll do in the near future.
Then as the company's fortunes rise, then so will yours. Of course, if you're going to take equity at all, you need to have them make the case, and you need to believe it. Otherwise, keep working at this job long enough to get a new one, and let the chips fall where they may.
"et them know that you feel you're not being adequately compensated, and you've been thinking of starting a job hunt, but that your sense of loyalty dictates that you let them know now"
I absolutely would not do this. Wait until you have other offers, if you play your cards now they could withhold giving you a reference or not as good of one as you truly deserve since they know it will be to their detriment.
Do what is best for yourself, not some startup which has clearly illustrated, by the facts presented, that it does not value you as an employee. Someone else will, go find them--you owe it to yourself.
As jfarmer said above: the kind of company that takes advantage of you when you're ignorant isn't the kind of company you want to work for even after you're fully-informed and can renegotiate a better deal.
In the end if you're not fighting your own corner compensation wise why do you expect your boss to do so?
His incentive is to keep you happy enough to stay and be productive while spending as little money as possible.
If the OP is genuinely happy with the job itself there's no downside to simply voicing his actual dissatisfaction as long as he presents his employers, especially as he's presenting a clear solution to the problem.
In your solution he's got to spend a bunch of his spare time applying for jobs first, which could all be a waste of time.
Also your point about references makes no sense. If they're petty enough to be asses now, they'll be petty enough to be asses in the future.
If the OP is genuinely happy with the job itself
If your tech lead is using the word "stupid" to describe their loyalty, I'd say it's bad business. Note that the OP is not wondering whether they're underpaid or under-equitized, or any other in-kind value judgement, they're already past that. It's now a matter of pulling a simple switch and bailing into a seller's market. Competent C-levels avoid this situation, especially in a startup environment where the midstream boatchanging of technical leadership can have painful consequences.
It's irresponsible for a company leader to exploit a crucial employee who can learn the truth about their situation, not that letting the launch slip by a year doesn't already mark them as possibly-incompetent. I can't recall if it's Fred Brooks or something possibly-apocryphal, but the rule of thumb that I've heard is that schedules slip by the units the milestone is measured. If the deadline is "two months from now," the schedule will slip by two-month periods. Slipping by a year? The business may not even get off the ground. I realize that it may have slipped by a year in two month increments (e.g.), but in hindsight the company's momentum sure doesn't look healthy.
In your solution he's got to spend a bunch of his spare time applying for jobs first, which could all be a waste of time
Pure FUD.
If they're petty enough to be asses now, they'll be petty enough to be asses in the future.
True that.