SpaceX's long-anticipated IPO is hours away from reshaping the fortunes of thousands of employees.

The listing, set for this Friday, is expected to mint millionaires not only among senior engineers and executives, but also among blue-collar workers, including cooks and welders, who received equity as part of their compensation packages.

The windfall is heavily concentrated around Brownsville, Texas, one of the poorest cities in the US, where SpaceX employs more than 3,000 people at its Starbase facility.

What makes this IPO unusual, even by Silicon Valley standards, is how far down the organisational chart the equity grants appear to have reached.

Some estimates cited by media reports put the total number of newly minted millionaires across the entire company at around 4,000. However, the figures could not be independently verified.