diff --git a/core/kg/server/grpc_server.go b/core/kg/server/grpc_server.go
index 966029e..20aed55 100644
--- a/core/kg/server/grpc_server.go
+++ b/core/kg/server/grpc_server.go
@@ -5,6 +5,7 @@
 	"net"
 	"os"
 
+	"github.com/giolekva/pcloud/core/kg/common"
 	"github.com/giolekva/pcloud/core/kg/log"
 	"github.com/giolekva/pcloud/core/kg/model"
 	"github.com/giolekva/pcloud/core/kg/model/proto"
@@ -14,16 +15,16 @@
 
 // GRPCServerImpl grpc server implementation
 type GRPCServerImpl struct {
-	Log    loggerIface
+	Log    common.LoggerIface
 	srv    *grpc.Server
 	config *model.Config
-	app    appIface
+	app    common.AppIface
 }
 
 var _ Server = &GRPCServerImpl{}
 
 // NewGRPCServer creates new GRPC Server
-func NewGRPCServer(logger loggerIface, config *model.Config, app appIface) Server {
+func NewGRPCServer(logger common.LoggerIface, config *model.Config, app common.AppIface) Server {
 	a := &GRPCServerImpl{
 		Log:    logger,
 		config: config,
diff --git a/core/kg/server/http_server.go b/core/kg/server/http_server.go
index 67eab88..6b07914 100644
--- a/core/kg/server/http_server.go
+++ b/core/kg/server/http_server.go
@@ -8,6 +8,7 @@
 	"os"
 	"time"
 
+	"github.com/giolekva/pcloud/core/kg/common"
 	"github.com/giolekva/pcloud/core/kg/log"
 	"github.com/giolekva/pcloud/core/kg/model"
 	"github.com/giolekva/pcloud/core/kg/store"
@@ -16,7 +17,7 @@
 
 // HTTPServerImpl http server implementation
 type HTTPServerImpl struct {
-	Log    loggerIface
+	Log    common.LoggerIface
 	srv    *http.Server
 	root   *mux.Router
 	config *model.Config
@@ -26,7 +27,7 @@
 var _ Server = &HTTPServerImpl{}
 
 // NewHTTPServer creates new HTTP Server
-func NewHTTPServer(logger loggerIface, config *model.Config, store store.Store) Server {
+func NewHTTPServer(logger common.LoggerIface, config *model.Config, store store.Store) Server {
 	a := &HTTPServerImpl{
 		Log:    logger,
 		root:   mux.NewRouter(),
diff --git a/core/kg/server/interfaces.go b/core/kg/server/interfaces.go
deleted file mode 100644
index 0316ea6..0000000
--- a/core/kg/server/interfaces.go
+++ /dev/null
@@ -1,17 +0,0 @@
-package server
-
-import (
-	"github.com/giolekva/pcloud/core/kg/log"
-	"github.com/giolekva/pcloud/core/kg/model"
-)
-
-type loggerIface interface {
-	Debug(message string, fields ...log.Field)
-	Info(message string, fields ...log.Field)
-	Warn(message string, fields ...log.Field)
-	Error(message string, fields ...log.Field)
-}
-
-type appIface interface {
-	GetUser(userID string) (*model.User, error)
-}
diff --git a/core/kg/server/servers.go b/core/kg/server/servers.go
index 9d91b34..7773934 100644
--- a/core/kg/server/servers.go
+++ b/core/kg/server/servers.go
@@ -5,6 +5,7 @@
 	"os/signal"
 	"syscall"
 
+	"github.com/giolekva/pcloud/core/kg/common"
 	"github.com/giolekva/pcloud/core/kg/log"
 )
 
@@ -17,11 +18,11 @@
 // Servers represents different server services
 type Servers struct {
 	servers []Server
-	logger  loggerIface
+	logger  common.LoggerIface
 }
 
 // New provides new service application
-func New(logger loggerIface) *Servers {
+func New(logger common.LoggerIface) *Servers {
 	return &Servers{
 		logger: logger,
 	}
diff --git a/core/kg/server/servers_mock.go b/core/kg/server/servers_mock.go
index 2260d2c..e2b6afc 100644
--- a/core/kg/server/servers_mock.go
+++ b/core/kg/server/servers_mock.go
@@ -5,12 +5,13 @@
 	"time"
 
 	"github.com/giolekva/pcloud/core/kg/app"
+	"github.com/giolekva/pcloud/core/kg/common"
 	"github.com/giolekva/pcloud/core/kg/log"
 	"github.com/giolekva/pcloud/core/kg/model"
 )
 
 type MockServer struct {
-	App     appIface
+	App     common.AppIface
 	Servers []Server
 	Config  *model.Config
 }