Note that when interacting with the deployed front-end there is currently no notification system built-in. However, the app is very verbose and prints everything it's doing to the console - just hit CMD-SHIFT-I in Chrome or Brave (or google how to open console in your own browser) - and follow the messages there.
Also note that the front-end is really there for you as the NFT project lead. For your own stakers you should probably build a nicer one.
You don't need a rust
developer for that. You just need someone who can do front-end (js/ts + any of: react, vue, svelte).
Roll Your Own Option
Gem Farm is 100% open source so you can fork it / customize it to your own needs.
Note that deploying your own version on mainnet will cost you ~20 SOL. If you decide to do it - follow the README in the repo.
Also please note - neither of the 2 options (but especially the latter) include support. Read the docs and watch the videos - they have everything you'll need.