diff --git a/S32-io/IO-Socket-Async-UDP.t b/S32-io/IO-Socket-Async-UDP.t
index 4bce5873c7..639c6d63f6 100644
--- a/S32-io/IO-Socket-Async-UDP.t
+++ b/S32-io/IO-Socket-Async-UDP.t
@@ -1,45 +1,51 @@
 use v6;
 use Test;
 
-plan 3;
+plan 5;
 
 my $hostname = 'localhost';
 my $port = 5001;
 
 {
-    my $sock = IO::Socket::Async.bind-udp($hostname, $port);
+    my $s = IO::Socket::Async.bind-udp($hostname, $port);
     dies-ok { IO::Socket::Async.bind-udp($hostname, $port) },
         'Error on trying to re-use port with UDP bind';
-    $sock.close;
+    $s.close;
 }
 
 # Promise used to check listener received the correct data.
-my $rec-prom;
-
-# Listener
-{
-    my $sock = IO::Socket::Async.bind-udp($hostname, $port);
-    my $tap = $sock.Supply.tap: -> $chars {
-        if $chars.chars > 0 {
-            $rec-prom.keep($chars);
-        }
+my Promise $rec-prom;
+my $s = IO::Socket::Async.bind-udp($hostname, $port);
+my $tap = $s.Supply.tap: -> $chars {
+    if $chars.chars > 0 {
+        $rec-prom.keep($chars);
     }
 }
 
 # Client print-to
 {
-    $rec-prom = Promise.new;
-    my $sock = IO::Socket::Async.udp();
-    $sock.print-to($hostname, $port, "Unusually Dubious Protocol");
+    $rec-prom .= new;
+    my $c = IO::Socket::Async.udp();
+    $c.print-to($hostname, $port, "Unusually Dubious Protocol");
     is $rec-prom.result, "Unusually Dubious Protocol", "Sent/received data with UDP (print)";
-    $sock.close;
+    $c.close;
 }
 
 # Client write-to
 {
-    $rec-prom = Promise.new;
-    my $sock = IO::Socket::Async.udp();
-    $sock.write-to($hostname, $port, "Unhelpful Dataloss Protocol".encode('ascii'));
+    $rec-prom .= new;
+    my $c = IO::Socket::Async.udp();
+    $c.write-to($hostname, $port, "Unhelpful Dataloss Protocol".encode('ascii'));
     is $rec-prom.result, "Unhelpful Dataloss Protocol", "Sent/received data with UDP (write)";
-    $sock.close;
+    $c.close;
+}
+
+#?rakudo.jvm skip 'nqp::filenofh not yet implemented on the JVM'
+{
+    my $c = IO::Socket::Async.udp();
+    cmp-ok $s.native-descriptor, '>', -1, 'server file descriptor makes sense';
+    cmp-ok $c.native-descriptor, '>', -1, 'client file descriptor makes sense';
+    $c.close;
 }
+
+$s.close;
diff --git a/S32-io/IO-Socket-Async.t b/S32-io/IO-Socket-Async.t
index dfcc13a6bc..359e50e2db 100644
--- a/S32-io/IO-Socket-Async.t
+++ b/S32-io/IO-Socket-Async.t
@@ -1,7 +1,7 @@
 use v6;
 use Test;
 
-plan 38;
+plan 41;
 
 my $hostname = 'localhost';
 my $port = 5000;
@@ -292,3 +292,22 @@ for '127.0.0.1', '::1' -> $host {
     is @first-got.join(""), "hello first", "first server socket got the right message";
     is @second-got.join(""), "hello second", "second server socket got the right message";
 }
+
+#?rakudo.jvm skip 'nqp::filenofh not yet implemented on the JVM'
+{
+    my Promise $p .= new;
+    my $v = $p.vow;
+
+    my $s = IO::Socket::Async.listen('localhost', 0).tap(-> $c {
+        cmp-ok $c.native-descriptor, '>', -1, 'server peer file descriptor makes sense';
+        $v.keep: 1;
+    });
+    cmp-ok $s.native-descriptor, '>', -1, 'server file descriptor makes sense';
+
+    my $c = await IO::Socket::Async.connect: 'localhost', await $s.socket-port;
+    cmp-ok $c.native-descriptor, '>', -1, 'client file descriptor makes sense';
+
+    await $p;
+    $s.close;
+    $c.close;
+}