pir::loadlib__s('libjit_fb');
use NativeCall;

sub my_connect( OpaquePointer $client) returns Int is native('libmongoc') { ... }
sub mongo_count( OpaquePointer $client, Str $db, Str $ns, OpaquePointer $query ) returns Int is native('libmongoc') { ... }

my OpaquePointer $connection;
my_connect($connection);
'done'.say;
my OpaquePointer $bson;
mongo_count($connection,'test','test',$bson);
'done'.say;