Director Fede Alvarez sought out special effects crew from Aliens (1986) to work on the creatures. Physical sets, practical creatures, and miniatures were used wherever possible to help ground later VFX work.
The idea of an Alien film centering on younger characters was inspired by a deleted scene from Aliens (1986) that was later restored in the Special Edition. Fede Alvarez explained, "There's a moment where you see a bunch of kids running around the corridors of this colony. And I thought, 'Wow, what would it be like for those kids to grow up in a colony that still needs another 50 years to terraform?' So I remember thinking, 'If I ever tell a story in that world, I would definitely be interested in those kids when they reach their early twenties.'"
The film was originally scheduled to be released on Hulu, but it switched to a theatrical release in June 2023.
The films practical animatronic creature effects were created in collaboration between special effect companies Legacy Effects and Studio Gillis, both selected due to their staffs prior history with the Alien series. Legacy Effects is the successor to Stan Winston Studios, who worked on Aliens (1986), while Studio Gillis is the successor to Amalgamated Dynamics, who worked on Alien 3 (1992), Alien: Resurrection (1997), and the two Alien vs Predator films.