If it is an isolated program in development systems only, then you can legitimately hard code a few things as that is your exact requirement.
Use Macros to DEFINE a sy-sysid check and use statement STOP in the marco. Add a few global variables to the code in the macro as well and comments as warnings... :-)
That should do the trick. SAP does the same.
Else...
If sy-debug ='X' then STOP anyway.
However you must prevent the developers from using the system debugger and GOTO statement function to skip over the macro.
If you cannot control that, then you also cannot control them from changing the program either.
In that case you must restrict their authorizations to object names or isolate the coding to a package which blocks the debugger.
Hard call! You cannot realistically restrict someone who can insert code into a running program or system.
Cheers,
Julius