To add to what LanX said, eval effectively hides any errors that might occur when executing what's in the block.

Since this is a .pl file and require happens at runtime, you may get away with just checking if this file contains some expected characteristics before calling require - like actually existing (or containing some expected text). That said, it's better practice to create an actual Perl module and esure it can be found via @INC (i.e., via PERLLIB, PERL5LIB, or judicious use of FindBin + use lib ....