diff --git a/archiver.go b/archiver.go
index 06037183c..caa66e5a8 100644
--- a/archiver.go
+++ b/archiver.go
@@ -513,7 +513,11 @@ func (arch *Archiver) Snapshot(dir string, t *Tree, parentSnapshot backend.ID) (
 	// reset global stats
 	arch.updateStats = Stats{}
 
-	sn := NewSnapshot(dir)
+	sn, err := NewSnapshot(dir)
+	if err != nil {
+		return nil, nil, err
+	}
+
 	sn.Parent = parentSnapshot
 
 	blob, err := arch.saveTree(t)
diff --git a/snapshot.go b/snapshot.go
index ddda498b4..9548d616e 100644
--- a/snapshot.go
+++ b/snapshot.go
@@ -5,6 +5,7 @@ import (
 	"os"
 	"os/user"
 	"path/filepath"
+	"strconv"
 	"time"
 
 	"github.com/restic/restic/backend"
@@ -18,14 +19,14 @@ type Snapshot struct {
 	Dir      string     `json:"dir"`
 	Hostname string     `json:"hostname,omitempty"`
 	Username string     `json:"username,omitempty"`
-	UID      string     `json:"uid,omitempty"`
-	GID      string     `json:"gid,omitempty"`
+	UID      uint32     `json:"uid,omitempty"`
+	GID      uint32     `json:"gid,omitempty"`
 
 	id backend.ID // plaintext ID, used during restore
 	bl *BlobList
 }
 
-func NewSnapshot(dir string) *Snapshot {
+func NewSnapshot(dir string) (*Snapshot, error) {
 	d, err := filepath.Abs(dir)
 	if err != nil {
 		d = dir
@@ -44,11 +45,20 @@ func NewSnapshot(dir string) *Snapshot {
 	usr, err := user.Current()
 	if err == nil {
 		sn.Username = usr.Username
-		sn.UID = usr.Uid
-		sn.GID = usr.Gid
+		uid, err := strconv.ParseInt(usr.Uid, 10, 32)
+		if err != nil {
+			return nil, err
+		}
+		sn.UID = uint32(uid)
+
+		gid, err := strconv.ParseInt(usr.Gid, 10, 32)
+		if err != nil {
+			return nil, err
+		}
+		sn.GID = uint32(gid)
 	}
 
-	return sn
+	return sn, nil
 }
 
 func LoadSnapshot(ch *ContentHandler, id backend.ID) (*Snapshot, error) {
diff --git a/snapshot_test.go b/snapshot_test.go
index a2c0d0958..fd441d0a7 100644
--- a/snapshot_test.go
+++ b/snapshot_test.go
@@ -10,7 +10,8 @@ import (
 
 func testSnapshot(t *testing.T, be backend.Server) {
 	var err error
-	sn := restic.NewSnapshot("/home/foobar")
+	sn, err := restic.NewSnapshot("/home/foobar")
+	ok(t, err)
 	sn.Tree, err = backend.ParseID("c3ab8ff13720e8ad9047dd39466b3c8974e592c2fa383d4a3960714caef0c4f2")
 	ok(t, err)
 	sn.Time, err = time.Parse(time.RFC3339Nano, "2014-08-03T17:49:05.378595539+02:00")