This expansion has been in development for three years, and the demo is slated to drop in a couple of days, 'You will see our take on the Blue Shift remake, with all features of Black Mesa.
However, Half-Life did have expansions - it's how Gearbox started out - and those are being remade by fans to boot, with Blue Shift, centered around Barney Calhoun, seeing its first chapter come March 16. Black Mesa, a fan-made re-imagining of the first Half-Life, bringing it up to the standards of its sequel, came out of early access last year.