diff --git a/basis/alarms/alarms-tests.factor b/basis/alarms/alarms-tests.factor
index 8f7868324d..17dd08cfcf 100644
--- a/basis/alarms/alarms-tests.factor
+++ b/basis/alarms/alarms-tests.factor
@@ -1,5 +1,6 @@
 USING: alarms alarms.private kernel calendar sequences
-tools.test threads concurrency.count-downs ;
+tools.test threads concurrency.count-downs concurrency.promises
+fry tools.time math ;
 IN: alarms.tests
 
 [ ] [
@@ -14,3 +15,17 @@ IN: alarms.tests
     self [ resume ] curry instant later drop
     "test" suspend drop
 ] unit-test
+
+[ t ] [
+    [
+        <promise>
+        '[ t _ fulfill ] 5 seconds later drop
+    ] benchmark 4,000,000,000 >
+] unit-test
+
+[ { 3 } ] [
+    { 3 } dup
+    '[ 4 _ set-first ] 2 seconds later
+    1/2 seconds sleep
+    cancel-alarm
+] unit-test
diff --git a/basis/io/backend/unix/unix.factor b/basis/io/backend/unix/unix.factor
index 0e84f1b65e..972b2a5b07 100644
--- a/basis/io/backend/unix/unix.factor
+++ b/basis/io/backend/unix/unix.factor
@@ -144,7 +144,7 @@ M: stdin dispose*
         tri
     ] with-destructors ;
 
-: wait-for-stdin ( stdin -- n )
+: wait-for-stdin ( stdin -- size )
     [ control>> CHAR: X over io:stream-write1 io:stream-flush ]
     [ size>> ssize_t heap-size swap io:stream-read *int ]
     bi ;
@@ -160,7 +160,12 @@ M: stdin dispose*
     ] if ;
 
 M: stdin refill
-    [ buffer>> ] [ dup wait-for-stdin ] bi* refill-stdin f ;
+    '[
+        buffer>> _ dup wait-for-stdin refill-stdin f
+    ] with-timeout ;
+
+M: stdin cancel-operation
+    [ size>> ] [ control>> ] bi [ cancel-operation ] bi@ ;
 
 : control-write-fd ( -- fd ) &: control_write *uint ;