According to the book Giger's Alien, the eggs were originally meant to be housed in a completely separate architectural structure, shaped in the form of a massive pyramid. The origins of the pyramid are not clear.
More than 100 prop eggs were created for the scene of Kane's exploration of the "cave" under The Derelict. One special hero-egg prop was created with a top that could peel open by hydraulics. The scene of Kane being attacked was filmed on September 10, 1978.
Ridley Scott wanted an early warning system around the Alien eggs that would signal the eggs to the approach of a possible host organism. This effect was achieved through the use of a blue scanning laser that was projected through smoke to highlight the apparent membrane covering the eggs. The laser used was loaned to Scott by the rock group The Who.
Ridley Scott has stated in respect to the production of Alien that he wanted to make "a slasher movie in space". The Derelict is intended as an updated version of "a dark, old, haunted house", as is the Nostromo.