diff --git a/acme/dns_challenge.go b/acme/dns_challenge.go
index 659d7082..b7be186f 100644
--- a/acme/dns_challenge.go
+++ b/acme/dns_challenge.go
@@ -8,7 +8,6 @@ import (
 	"log"
 	"net"
 	"strings"
-	"time"
 
 	"github.com/miekg/dns"
 	"golang.org/x/net/publicsuffix"
@@ -256,26 +255,3 @@ func UnFqdn(name string) string {
 	}
 	return name
 }
-
-// WaitFor polls the given function 'f', once every 'interval' seconds, up to 'timeout' seconds.
-func WaitFor(timeout, interval int, f func() (bool, error)) error {
-	var lastErr string
-	timeup := time.After(time.Duration(timeout) * time.Second)
-	for {
-		select {
-		case <-timeup:
-			return fmt.Errorf("Time limit exceeded. Last error: %s", lastErr)
-		default:
-		}
-
-		stop, err := f()
-		if stop {
-			return nil
-		}
-		if err != nil {
-			lastErr = err.Error()
-		}
-
-		time.Sleep(time.Duration(interval) * time.Second)
-	}
-}
diff --git a/acme/dns_challenge_test.go b/acme/dns_challenge_test.go
index 760c7991..bfc66561 100644
--- a/acme/dns_challenge_test.go
+++ b/acme/dns_challenge_test.go
@@ -163,23 +163,3 @@ func TestCheckAuthoritativeNssErr(t *testing.T) {
 		}
 	}
 }
-
-func TestWaitForTimeout(t *testing.T) {
-	c := make(chan error)
-	go func() {
-		err := WaitFor(3, 1, func() (bool, error) {
-			return false, nil
-		})
-		c <- err
-	}()
-
-	timeout := time.After(4 * time.Second)
-	select {
-	case <-timeout:
-		t.Fatal("timeout exceeded")
-	case err := <-c:
-		if err == nil {
-			t.Errorf("expected timeout error; got %v", err)
-		}
-	}
-}
diff --git a/acme/utils.go b/acme/utils.go
new file mode 100644
index 00000000..937a8f2d
--- /dev/null
+++ b/acme/utils.go
@@ -0,0 +1,29 @@
+package acme
+
+import (
+	"fmt"
+	"time"
+)
+
+// WaitFor polls the given function 'f', once every 'interval' seconds, up to 'timeout' seconds.
+func WaitFor(timeout, interval time.Duration, f func() (bool, error)) error {
+	var lastErr string
+	timeup := time.After(timeout * time.Second)
+	for {
+		select {
+		case <-timeup:
+			return fmt.Errorf("Time limit exceeded. Last error: %s", lastErr)
+		default:
+		}
+
+		stop, err := f()
+		if stop {
+			return nil
+		}
+		if err != nil {
+			lastErr = err.Error()
+		}
+
+		time.Sleep(interval * time.Second)
+	}
+}
diff --git a/acme/utils_test.go b/acme/utils_test.go
new file mode 100644
index 00000000..cb837cd5
--- /dev/null
+++ b/acme/utils_test.go
@@ -0,0 +1,26 @@
+package acme
+
+import (
+	"testing"
+	"time"
+)
+
+func TestWaitForTimeout(t *testing.T) {
+	c := make(chan error)
+	go func() {
+		err := WaitFor(3, 1, func() (bool, error) {
+			return false, nil
+		})
+		c <- err
+	}()
+
+	timeout := time.After(4 * time.Second)
+	select {
+	case <-timeout:
+		t.Fatal("timeout exceeded")
+	case err := <-c:
+		if err == nil {
+			t.Errorf("expected timeout error; got %v", err)
+		}
+	}
+}