Smartmatch is experimental at t/1.t line 21.
t/1.t .. 
1..6
ok 1
ok 2
ok 3
ok 4
ok 5
[2021-07-16 16:16:01] listening for DNS queries on address 127.0.0.1 and port 16722
ok 6
ok
All tests successful.
Files=1, Tests=6,  1 wallclock secs ( 0.01 usr  0.01 sys +  0.40 cusr  0.03 csys =  0.45 CPU)
Result: PASS