diff --git a/kadai4/execjosh/internal/jinja/jinja.go b/kadai4/execjosh/internal/jinja/jinja.go
new file mode 100644
index 0000000..6267531
--- /dev/null
+++ b/kadai4/execjosh/internal/jinja/jinja.go
@@ -0,0 +1,52 @@
+package jinja
+
+import (
+	"math/rand"
+	"sync"
+	"time"
+)
+
+var blessings = []string{
+	"大吉",
+	"吉",
+	"中吉",
+	"小吉",
+	"半吉",
+	"末吉",
+	"末小吉",
+	"平",
+	"凶",
+	"小凶",
+	"半凶",
+	"末凶",
+	"大凶",
+}
+var blessingCount = len(blessings)
+
+// A Jinja that provides random omikuji
+type Jinja struct {
+	lk  sync.Mutex
+	rng *rand.Rand
+}
+
+// New creates and initializes a new Jinja
+func New(seed int64) *Jinja {
+	return &Jinja{
+		rng: rand.New(rand.NewSource(seed)),
+	}
+}
+
+// GetBlessing returns an blessing based on the current time.
+// For 1/1-1/3, it returns always "大吉".
+// For all other dates, it returns a random blessing.
+func (m *Jinja) GetBlessing(now time.Time) string {
+	if now.YearDay() <= 3 {
+		return "大吉"
+	}
+
+	m.lk.Lock()
+	n := m.rng.Intn(blessingCount)
+	m.lk.Unlock()
+
+	return blessings[n]
+}
diff --git a/kadai4/execjosh/internal/jinja/jinja_test.go b/kadai4/execjosh/internal/jinja/jinja_test.go
new file mode 100644
index 0000000..493a1df
--- /dev/null
+++ b/kadai4/execjosh/internal/jinja/jinja_test.go
@@ -0,0 +1,46 @@
+package jinja_test
+
+import (
+	"fmt"
+	"testing"
+	"time"
+
+	"github.com/gopherdojo/dojo1/kadai4/execjosh/internal/jinja"
+)
+
+func TestGetBlessing(t *testing.T) {
+	expectedValues := []struct {
+		now      time.Time
+		seed     int64
+		expected []string
+	}{
+		{time.Date(2018, time.January, 1, 0, 0, 0, 0, time.UTC), 1, []string{"大吉", "大吉", "大吉"}},
+		{time.Date(2018, time.January, 2, 0, 0, 0, 0, time.UTC), 1, []string{"大吉", "大吉", "大吉"}},
+		{time.Date(2018, time.January, 3, 0, 0, 0, 0, time.UTC), 1, []string{"大吉", "大吉", "大吉"}},
+
+		{time.Date(2018, time.January, 1, 0, 0, 0, 0, time.UTC), 2, []string{"大吉", "大吉", "大吉"}},
+		{time.Date(2018, time.January, 2, 0, 0, 0, 0, time.UTC), 2, []string{"大吉", "大吉", "大吉"}},
+		{time.Date(2018, time.January, 3, 0, 0, 0, 0, time.UTC), 2, []string{"大吉", "大吉", "大吉"}},
+
+		{time.Date(2018, time.January, 1, 0, 0, 0, 0, time.UTC), time.Now().UnixNano(), []string{"大吉", "大吉", "大吉"}},
+		{time.Date(2018, time.January, 2, 0, 0, 0, 0, time.UTC), time.Now().UnixNano(), []string{"大吉", "大吉", "大吉"}},
+		{time.Date(2018, time.January, 3, 0, 0, 0, 0, time.UTC), time.Now().UnixNano(), []string{"大吉", "大吉", "大吉"}},
+
+		{time.Date(2018, time.May, 4, 0, 0, 0, 0, time.UTC), 1234567890, []string{"末小吉", "末吉", "末小吉", "末凶"}},
+		{time.Date(2018, time.May, 17, 0, 0, 0, 0, time.UTC), 123567890, []string{"平", "平", "半吉", "末吉"}},
+	}
+
+	for _, tc := range expectedValues {
+		tc := tc
+		j := jinja.New(tc.seed)
+		for _, expected := range tc.expected {
+			expected := expected
+			j := j
+			actual := j.GetBlessing(tc.now)
+			if expected != actual {
+				fmt.Printf("expected '%v' but got '%v'\n", expected, actual)
+				t.Fail()
+			}
+		}
+	}
+}
diff --git a/kadai4/execjosh/internal/jinja/omikuji.go b/kadai4/execjosh/internal/jinja/omikuji.go
new file mode 100644
index 0000000..6fbd72f
--- /dev/null
+++ b/kadai4/execjosh/internal/jinja/omikuji.go
@@ -0,0 +1,6 @@
+package jinja
+
+// An Omikuji holds a blessing
+type Omikuji struct {
+	Blessing string `json:"blessing"`
+}
diff --git a/kadai4/execjosh/main.go b/kadai4/execjosh/main.go
new file mode 100644
index 0000000..e4807a6
--- /dev/null
+++ b/kadai4/execjosh/main.go
@@ -0,0 +1,21 @@
+package main
+
+import (
+	"encoding/json"
+	"net/http"
+	"time"
+
+	"github.com/gopherdojo/dojo1/kadai4/execjosh/internal/jinja"
+)
+
+func main() {
+	j := jinja.New(time.Now().UnixNano())
+	handler := func(w http.ResponseWriter, r *http.Request) {
+		b := j.GetBlessing(time.Now())
+		mkj := &jinja.Omikuji{Blessing: b}
+		json.NewEncoder(w).Encode(mkj)
+	}
+
+	http.HandleFunc("/omikuji", handler)
+	http.ListenAndServe(":8080", nil)
+}