Just use require Capture::Tiny at runtime, like you already did in your code.

The thing you are missing is that Perl doesn't know that capture should become a function. You can either try to predeclare capture as subroutine to tell that you expect a capture subroutine:

sub capture(&@);

...
require Capture::Tiny;
Capture::Tiny->import('capture');
capture {
} ...;
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Or go the more explicit route of calling capture in a way that doesn't need parser gymnastics:

capture( sub { ... }, ... );
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