Don't know where you're located. But In EU, the employer only own the code you type at your work (or during your work time if remote) It's in the contract. He

Don't know where you're located. But In EU, the employer only own the code you type at your work (or during your work time if remote) It's in the contract. He can only bother you if you code for money outside your work. It can be seen as a second job. Again check your contract.