diff --git a/pttodo/schedule.go b/pttodo/schedule.go
index 2cc18cd..6c3de04 100644
--- a/pttodo/schedule.go
+++ b/pttodo/schedule.go
@@ -1,3 +1,13 @@
 package pttodo
 
+import "encoding/json"
+
 type Schedule string
+
+func (schedule Schedule) MarshalJSON() ([]byte, error) {
+	return json.Marshal(string(schedule))
+}
+
+func (schedule *Schedule) UnmarshalJSON(b []byte) error {
+	return json.Unmarshal(b, (*string)(schedule))
+}
diff --git a/pttodo/schedule_test.go b/pttodo/schedule_test.go
new file mode 100644
index 0000000..846f853
--- /dev/null
+++ b/pttodo/schedule_test.go
@@ -0,0 +1,47 @@
+package pttodo
+
+import (
+	"bytes"
+	"encoding/json"
+	"testing"
+)
+
+func TestJSONSchedule(t *testing.T) {
+	cases := map[string]struct {
+		input          string
+		wantMarshalled string
+	}{
+		"cron": {
+			input:          "* * * * *",
+			wantMarshalled: `"* * * * *"`,
+		},
+		"int": {
+			input:          "123",
+			wantMarshalled: `"123"`,
+		},
+		"duration": {
+			input:          "1h",
+			wantMarshalled: `"1h"`,
+		},
+	}
+
+	for name, d := range cases {
+		c := d
+		t.Run(name, func(t *testing.T) {
+			gotMarshalled, err := json.Marshal(Schedule(c.input))
+			if err != nil {
+				t.Fatal(err)
+			}
+			if !bytes.Equal([]byte(c.wantMarshalled), gotMarshalled) {
+				t.Fatal(c.wantMarshalled, gotMarshalled)
+			}
+			var got Schedule
+			if err := json.Unmarshal(gotMarshalled, &got); err != nil {
+				t.Fatal(err)
+			}
+			if string(got) != c.input {
+				t.Fatal(got)
+			}
+		})
+	}
+}
diff --git a/pttodo/ts.go b/pttodo/ts.go
index 4eebf9a..737a4c3 100644
--- a/pttodo/ts.go
+++ b/pttodo/ts.go
@@ -1,3 +1,19 @@
 package pttodo
 
-type TS string
+import (
+	"encoding/json"
+	"time"
+)
+
+type TS int64
+
+func (ts TS) MarshalJSON() ([]byte, error) {
+	if ts == 0 {
+		ts = TS(time.Now().Unix())
+	}
+	return json.Marshal(int64(ts))
+}
+
+func (ts *TS) UnmarshalJSON(b []byte) error {
+	return json.Unmarshal(b, (*int64)(ts))
+}
diff --git a/pttodo/ts_test.go b/pttodo/ts_test.go
new file mode 100644
index 0000000..23dc44f
--- /dev/null
+++ b/pttodo/ts_test.go
@@ -0,0 +1,30 @@
+package pttodo
+
+import (
+	"encoding/json"
+	"testing"
+	"time"
+)
+
+func TestJSONTS(t *testing.T) {
+	ts := TS(time.Now().Unix())
+	js, err := json.Marshal(ts)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	var ts2 TS
+	if err := json.Unmarshal(js, &ts2); err != nil {
+		t.Fatal(err)
+	}
+	if ts != ts2 {
+		t.Fatal(ts2)
+	}
+
+	if err := json.Unmarshal([]byte(`123`), &ts2); err != nil {
+		t.Fatal(err)
+	}
+	if 123 != ts2 {
+		t.Fatal(ts2)
+	}
+}