Hacking Question: Hiring a developer to run bitcoin core to process bitcoin payments on site
If you want to accept and hold bitcoins it is trivial to generate a large number of addresses offline and feed the public addresses (not the private keys) to the web developer.  He would not have any access to the funds.  Also as suggested in the comments you could use an HD wallet and provide the XPUB key to the developer.  This would allow him to generate only the addresses that you have private keys for.  

For example the electrum wallet is an HD wallet that would provide the required capabilities.