How to order a work and get all the rights to it?

Question

Freelance

I'm going to order a job - a large javascript script for the game. In this regard, several questions arose:

• What about code rights? The freelancer writes the script, gives it to me, I put it in the game, can’t he then send from him “you stole this code, remove everything, but I will sue you, etc.”?
  
• What should I do to prevent this?
  
• Any special contract to conclude? (If anything, then I am not a company or an individual entrepreneur, I am a simple individual) And how are contracts concluded, taking into account the fact that the freelancer and I are at a distance and communicate only via the Internet? You can't even sign with a seal.
  
• How can I prevent a freelancer from redistributing this code? Or how to claim the code if I see it somewhere on the Internet (means either the freelancer posted it himself, or shared it with someone and this someone posted it)?
  

Answer 1

Contract for services. One of the points is "Rights to the source code" where you write all the details.
Somehow:
The code received under this agreement is the property of the customer, the contractor transfers all rights to its use, distribution and modification to the customer and undertakes not to use it in the future for his own purposes. All payments for the code are made under this agreement and are final, the developer waives the rights to receive possible profits and / or royalties in the future.
The contract is sent by registered mail after signing a copy. Time from Voronezh to Moscow, Peter 2-3 days from Voronezh to Tallinn 4 days.

Answer 2

with a competent contract, a freelancer should still be able to stay for you))