- He made a great home investment, apparently bought cheap and later was able to rent it for a lot of money. This is good for him, but somewhat lucky (or, alternative, a spark of insight into real-estate)
- He made nice returns on stocks
Both are fine, but not a part of "corporate programmer salary"
A typical mortgage around here is about 1/3rd of your income. So being able to basically have other people pay 2 mortgages for you is _huge_.
He also mentions he bough a bunch of Cisco stock for 7$ which he later got to sell for 30$. That's more than a 300% return, so depending on how much he invested, that can easily amount to a hefty chunk of cash as well.
But the HN posting title seems to have been adjusted from the original title (which doesn't mention corporate programmer salary).
Earnings received by a partner and shared expenses makes a dramatic difference to wealth accumulation. Where I live, if I earn double what two people in a relationship each individually earn, the couple make an extra 12% after-tax vs. what I do because they are taxed at a lower rate on their lower individual incomes. Furthermore, while two people eat and poop twice as much as one person, the greatest expenses (living) can often be shared.
I thought this article counter-balances some of the many startup success stories we read about here. All great success seems to involve exceptional circumstances, hard work and good luck.
I guess the point is that startups aren't the ONLY way for programmers to get lucky.