diff --git a/container/ethereum.go b/container/ethereum.go
index 03479a6f..8eba7575 100644
--- a/container/ethereum.go
+++ b/container/ethereum.go
@@ -32,7 +32,7 @@ import (
 	"github.com/docker/go-connections/nat"
 	"github.com/getamis/go-ethereum/cmd/utils"
 	"github.com/getamis/go-ethereum/ethclient"
-	"github.com/getamis/istanbul-tools/core"
+	"github.com/getamis/istanbul-tools/core/genesis"
 )
 
 const (
@@ -101,12 +101,12 @@ func (eth *ethereum) Init(genesisFile string) error {
 				"init",
 				"--" + utils.DataDirFlag.Name,
 				eth.dataDir,
-				filepath.Join("/", core.GenesisJson),
+				filepath.Join("/", genesis.FileName),
 			},
 		},
 		&container.HostConfig{
 			Binds: []string{
-				genesisFile + ":" + filepath.Join("/", core.GenesisJson),
+				genesisFile + ":" + filepath.Join("/", genesis.FileName),
 				eth.hostDataDir + ":" + eth.dataDir,
 			},
 		}, nil, "")
diff --git a/container/ethereum_test.go b/container/ethereum_test.go
index 045ce519..103a6a11 100644
--- a/container/ethereum_test.go
+++ b/container/ethereum_test.go
@@ -22,6 +22,7 @@ import (
 	"testing"
 
 	"github.com/getamis/istanbul-tools/core"
+	"github.com/getamis/istanbul-tools/core/genesis"
 )
 
 func TestEthereumContainer(t *testing.T) {
@@ -46,7 +47,7 @@ func TestEthereumContainer(t *testing.T) {
 			Logging(true),
 		)
 
-		err := geth.Init(filepath.Join(env.DataDir, core.GenesisJson))
+		err := geth.Init(filepath.Join(env.DataDir, genesis.FileName))
 		if err != nil {
 			t.Error(err)
 		}
diff --git a/core/cluster.go b/core/cluster.go
index 8b95aebe..7d5eb7b1 100644
--- a/core/cluster.go
+++ b/core/cluster.go
@@ -31,6 +31,7 @@ import (
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/crypto"
 	"github.com/ethereum/go-ethereum/p2p/discover"
+	"github.com/getamis/istanbul-tools/core/genesis"
 	"github.com/satori/go.uuid"
 )
 
@@ -43,7 +44,6 @@ const (
 
 	clientIdentifier = "geth"
 	staticNodeJson   = "static-nodes.json"
-	GenesisJson      = "genesis.json"
 )
 
 type Env struct {
@@ -106,9 +106,9 @@ func SetupNodes(envs []*Env) error {
 	}
 
 	addrs := toAddress(envs)
-	genesis := GenerateGenesis(addrs)
+	g := genesis.New(addrs)
 	for _, env := range envs {
-		if err := saveGenesis(env.DataDir, genesis); err != nil {
+		if err := genesis.Save(env.DataDir, g); err != nil {
 			return err
 		}
 	}
diff --git a/core/genesis.go b/core/genesis/genesis.go
similarity index 87%
rename from core/genesis.go
rename to core/genesis/genesis.go
index 4c932d10..d3cb63e1 100644
--- a/core/genesis.go
+++ b/core/genesis/genesis.go
@@ -14,7 +14,7 @@
 // You should have received a copy of the GNU Lesser General Public License
 // along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
 
-package core
+package genesis
 
 import (
 	"encoding/json"
@@ -23,6 +23,7 @@ import (
 	"math/big"
 	"path/filepath"
 	"time"
+	"log"
 
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/common/hexutil"
@@ -33,10 +34,14 @@ import (
 	"github.com/getamis/istanbul-tools/cmd/istanbul/extradata"
 )
 
-func GenerateGenesis(addrs []common.Address) *core.Genesis {
+const (
+	FileName = "genesis.json"
+)
+
+func New(addrs []common.Address) *core.Genesis {
 	extraData, err := extradata.Encode("0x00", addrs)
 	if err != nil {
-		panic(fmt.Sprintf("%s%s", "Failed to generate genesis", err))
+		log.Fatalf("Failed to generate genesis, err:%s", err)
 	}
 
 	return &core.Genesis{
@@ -59,8 +64,8 @@ func GenerateGenesis(addrs []common.Address) *core.Genesis {
 	}
 }
 
-func saveGenesis(dataDir string, genesis *core.Genesis) error {
-	filePath := filepath.Join(dataDir, GenesisJson)
+func Save(dataDir string, genesis *core.Genesis) error {
+	filePath := filepath.Join(dataDir, FileName)
 
 	raw, err := json.Marshal(genesis)
 	if err != nil {