While this is a generous offer, a $36k salary equivalent for full-time programming work, with no other job for external income, isn't feasible.
Since the OP doesn't want anything in return, it's possible that this could be considered a gift. If true, then the transfer would be tax (and social security) free in the US.
The OP is paying tax/SS on the money because the project is not a tax-exempt charitable org.
So, might be considered closer to 50k in equivalent salary.
https://en.wikipedia.org/wiki/Gift_tax_in_the_United_States
There are two levels of exemption from the gift tax. First, gifts of up to the annual exclusion ($14,000 per recipient in 2015) incur no tax or filing requirement. By splitting their gifts, married couples can give up to twice this amount tax-free. Note that each giver and recipient pair has their own unique annual exclusion; a giver can give to any number of recipients and the exclusion is not affected by other gifts that recipient may have received from others.
Second, gifts in excess of the annual exclusion may still be tax-free up to the lifetime estate basic exclusion amount ($5,340,000 in 2014, $5,430,000 in 2015), although for estates over that amount such gifts might increase estate taxes. Taxpayers that expect to have a taxable estate may sometimes prefer to pay gift taxes as they occur, rather than saving them up as part of the estate.
For something to be a gift, the giver can have no consideration
https://www.irs.gov/Businesses/Small-Businesses-&-Self-Emplo...
What is considered a gift?
Any transfer to an individual, either directly or indirectly, where full consideration (measured in money or money's worth) is not received in return.
The OP wants you to work on your project -- it's not clear what happens if you don't do that. If the OP does not get the money back or any other consideration, I believe that an accountant and lawyer could structure this as a gift. The OP will have to file and it counts against their lifetime exemption, but there is no tax (I believe -- talk to an accountant)
But it's more than acceptable in many parts of the world.
And yes, I wouldn't expect someone with a family in the Bay Area to be interested.
At least, a family to support. A family supporting them, maybe...