Move as much code as possible to ServerScriptService or ServerStorage . These scripts do not replicate to the player's computer, making them impossible for standard exploiters to steal.
In the context of Pet Simulator X (PSX) on Roblox, "Anti-Steal" typically refers to security measures meant to prevent either by other developers or in-game pet theft by hackers and scammers. For Game Developers: Protecting Assets Pet Simulator X - Anti Steal Download
Avoid using "free models" from the Roblox Marketplace that might contain hidden "backdoors"—malicious scripts that allow hackers to gain admin access and download your place file. Move as much code as possible to ServerScriptService
Some developers use obfuscation (making code unreadable) or "anti-copy" scripts. However, these are often considered "security through obscurity" and can sometimes be bypassed by determined exploiters. For Players: Preventing Pet Theft For Game Developers: Protecting Assets Avoid using "free
If you are building a PSX-style game and want to prevent others from downloading or "stealing" your work, keep in mind that anything on the client side can technically be accessed by exploiters.