Also missing, any discussion of equity-like or profit-participatory structures from LPs (limited partnerships).

Technologists joining one of these should know the "business domain" "partners" are either buying into or awarded partnership interests, but structures can be available for non-business domain roles (in firms that think technology isn't in their business domain cough), such as "profits interests", "synthetic equity", "phantom equity", or etc.*

If the firm has a product and you're helping build it, look for equity-like that let you not only share in profits (if any, most starting things don't have profits) but have a stake in capital events (from asset sale to IPO).

Think of these two forms as something like dividends and something like a combination of options and RSUs. If the profit component is intended as part of annual comp, it should pay at 100% from the start even if you don't "own" it until you vest. Meanwhile if it's a future reward, then both it and the capital-like would have a "tail" that remains in effect if profits or a capital event happens after you leave.

These are very complicated and very bespoke per firm since they are 'made out of' the partnership interests of the LP where ownership is handled as "capital accounts" and may have no accounting method for "goodwill" value separate from partner capital accounts. In such cases, generally partners have shaved off some portion of their rights and allocated those rights to employees, and the mechanisms of this "waterfall" amount to where you stand in that line if at all.

Ideally (a) seek advice from someone experienced with these that (b) you don't have to spend $1200 an hour on.

* Partnerships that understand their business domain is in the technology business — since technology is just another word for tools, and business humans should be tool crafters too — will be using this and have told you about it during interview, and it will all go more smoothly.