diff --git a/basket/dto/dto.go b/basket/dto/basket.go
similarity index 100%
rename from basket/dto/dto.go
rename to basket/dto/basket.go
diff --git a/basket/entity/entity.go b/basket/entity/basket.go
similarity index 100%
rename from basket/entity/entity.go
rename to basket/entity/basket.go
diff --git a/basket/model/basket.go b/basket/model/basket.go
new file mode 100644
index 0000000..68605fd
--- /dev/null
+++ b/basket/model/basket.go
@@ -0,0 +1,20 @@
+package basket
+
+import (
+	"time"
+)
+
+type BasketModel struct {
+	State     string    `db:"state" json:"state"`
+	CreatedAt time.Time `db:"created_at" json:"created_at"`
+	UpdatedAt time.Time `db:"updated_at" json:"updated_at,omitempty"`
+}
+
+type BasketItemModel struct {
+	BasketID  string    `db:"basket_id" json:"basket_id"`
+	ProductID int       `db:"product_id" json:"product_id"`
+	Quantity  int       `db:"quantity" json:"quantity"`
+	Price     float64   `db:"price" json:"price"`
+	CreatedAt time.Time `db:"created_at" json:"created_at"`
+	UpdatedAt time.Time `db:"updated_at" json:"updated_at,omitempty"`
+}
diff --git a/basket/model/model.go b/basket/model/model.go
deleted file mode 100644
index 6acffac..0000000
--- a/basket/model/model.go
+++ /dev/null
@@ -1,22 +0,0 @@
-package basket
-
-import (
-	"github.com/jackc/pgtype"
-)
-
-type BasketModel struct {
-	// ID        string           `db:"id" json:"id"`
-	State     string           `db:"state" json:"state"`
-	CreatedAt pgtype.Timestamp `db:"created_at" json:"created_at"`
-	UpdatedAt pgtype.Timestamp `db:"updated_at" json:"updated_at,omitempty"`
-}
-
-type BasketItemModel struct {
-	// ID        string           `db:"id" json:"id"`
-	BasketID  string           `db:"basket_id" json:"basket_id"`
-	ProductID int              `db:"product_id" json:"product_id"`
-	Quantity  int              `db:"quantity" json:"quantity"`
-	Price     float64          `db:"price" json:"price"`
-	CreatedAt pgtype.Timestamp `db:"created_at" json:"created_at"`
-	UpdatedAt pgtype.Timestamp `db:"updated_at" json:"updated_at,omitempty"`
-}
diff --git a/catalog/dto/dto.go b/catalog/dto/product.go
similarity index 63%
rename from catalog/dto/dto.go
rename to catalog/dto/product.go
index b5ba12a..31a1322 100644
--- a/catalog/dto/dto.go
+++ b/catalog/dto/product.go
@@ -4,11 +4,11 @@ import (
 	"time"
 )
 
-type GetProductRequest struct {
+type GetProductRequestDTO struct {
 	ProductID int `json:"product_id"`
 }
 
-type GetProductResponse struct {
+type GetProductResponseDTO struct {
 	ID        int           `json:"id"`
 	PID       string        `json:"pid"`
 	Name      string        `json:"name"`
@@ -17,30 +17,30 @@ type GetProductResponse struct {
 	UpdatedAt time.Duration `json:"updated_at,omitempty"`
 }
 
-type GetProductListRequest struct {
+type GetProductListRequestDTO struct {
 	CategoryID int `json:"category_id"`
 }
 
-type GetProductListResponse struct {
-	Products []GetProductResponse `json:"products"`
+type GetProductListResponseDTO struct {
+	Products []GetProductResponseDTO `json:"products"`
 }
 
-type AddProductToBasketRequest struct {
+type AddProductToBasketRequestDTO struct {
 	ProductID int `json:"product_id"`
 	Quantity  int `json:"quantity"`
 }
 
-type AddProductToBasketResponse struct {
+type AddProductToBasketResponseDTO struct {
 	ProductID int    `json:"product_id"`
 	BasketID  string `json:"basket_id"`
 }
 
-type RemoveProductFromBasketRequest struct {
+type RemoveProductFromBasketRequestDTO struct {
 	ProductID int `json:"product_id"`
 	Quantity  int `json:"quantity"`
 }
 
-type RemoveProductFromBasketResponse struct {
+type RemoveProductFromBasketResponseDTO struct {
 	ProductID int    `json:"product_id"`
 	BasketID  string `json:"basket_id"`
 }
diff --git a/catalog/entity/entity.go b/catalog/entity/product.go
similarity index 100%
rename from catalog/entity/entity.go
rename to catalog/entity/product.go
diff --git a/catalog/model/model.go b/catalog/model/model.go
deleted file mode 100644
index 383a068..0000000
--- a/catalog/model/model.go
+++ /dev/null
@@ -1,12 +0,0 @@
-package model
-
-import "github.com/jackc/pgtype"
-
-type ProductModel struct {
-	// ID        int              `db:"id"`
-	PID       string           `db:"pid"`
-	Name      string           `db:"name"`
-	Price     float64          `db:"price"`
-	CreatedAt pgtype.Timestamp `db:"created_at"`
-	UpdatedAt pgtype.Timestamp `db:"updated_at,omitempty"`
-}
diff --git a/catalog/model/product.go b/catalog/model/product.go
new file mode 100644
index 0000000..164ee72
--- /dev/null
+++ b/catalog/model/product.go
@@ -0,0 +1,13 @@
+package model
+
+import (
+	"time"
+)
+
+type ProductModel struct {
+	PID       string    `db:"pid"`
+	Name      string    `db:"name"`
+	Price     float64   `db:"price"`
+	CreatedAt time.Time `db:"created_at"`
+	UpdatedAt time.Time `db:"updated_at,omitempty"`
+}
diff --git a/common/dto/error.go b/common/dto/error.go
index 324a0c1..f6429ea 100644
--- a/common/dto/error.go
+++ b/common/dto/error.go
@@ -4,6 +4,6 @@ type ErrorResponseDTO struct {
 	Error string `json:"error"`
 }
 
-func Error(err string) *ErrorResponseDTO { // FIXME Can DTOs have functions?
+func NewError(err string) *ErrorResponseDTO { // FIXME Can DTOs have functions?
 	return &ErrorResponseDTO{err}
 }
diff --git a/common/vo/currency.go b/common/vo/currency.go
index 114d287..e1cfe01 100644
--- a/common/vo/currency.go
+++ b/common/vo/currency.go
@@ -34,7 +34,7 @@ func (c *Currency) Get() *Currency {
 		return curr
 	}
 
-	return c.getDefault()
+	return c.Default()
 }
 
 func (c *Currency) Equals(oc *Currency) bool {
diff --git a/identity/dto/dto.go b/identity/dto/auth.go
similarity index 100%
rename from identity/dto/dto.go
rename to identity/dto/auth.go
diff --git a/order/dto/dto.go b/order/dto/order.go
similarity index 100%
rename from order/dto/dto.go
rename to order/dto/order.go
diff --git a/order/entity/entity.go b/order/entity/order.go
similarity index 100%
rename from order/entity/entity.go
rename to order/entity/order.go
diff --git a/order/model/model.go b/order/model/model.go
deleted file mode 100644
index ce197e5..0000000
--- a/order/model/model.go
+++ /dev/null
@@ -1,20 +0,0 @@
-package order
-
-import "github.com/jackc/pgtype"
-
-type OrderModel struct {
-	// ID        string           `db:"id" json:"id"`
-	State     string           `db:"state" json:"state"`
-	CreatedAt pgtype.Timestamp `db:"created_at" json:"created_at"`
-	UpdatedAt pgtype.Timestamp `db:"updated_at" json:"updated_at,omitempty"`
-}
-
-type OrderItemModel struct {
-	// ID        string           `db:"id" json:"id"`
-	OrderID   string           `db:"order_id" json:"order_id"`
-	ProductID int              `db:"product_id" json:"product_id"`
-	Quantity  int              `db:"quantity" json:"quantity"`
-	Price     float64          `db:"price" json:"price"`
-	CreatedAt pgtype.Timestamp `db:"created_at" json:"created_at"`
-	UpdatedAt pgtype.Timestamp `db:"updated_at" json:"updated_at,omitempty"`
-}
diff --git a/order/model/order.go b/order/model/order.go
new file mode 100644
index 0000000..069ed30
--- /dev/null
+++ b/order/model/order.go
@@ -0,0 +1,18 @@
+package order
+
+import "time"
+
+type OrderModel struct {
+	State     string    `db:"state" json:"state"`
+	CreatedAt time.Time `db:"created_at" json:"created_at"`
+	UpdatedAt time.Time `db:"updated_at" json:"updated_at,omitempty"`
+}
+
+type OrderItemModel struct {
+	OrderID   string    `db:"order_id" json:"order_id"`
+	ProductID int       `db:"product_id" json:"product_id"`
+	Quantity  int       `db:"quantity" json:"quantity"`
+	Price     float64   `db:"price" json:"price"`
+	CreatedAt time.Time `db:"created_at" json:"created_at"`
+	UpdatedAt time.Time `db:"updated_at" json:"updated_at,omitempty"`
+}
diff --git a/pricing/dto/dto.go b/pricing/dto/product_price.go
similarity index 100%
rename from pricing/dto/dto.go
rename to pricing/dto/product_price.go
diff --git a/pricing/entity/entity.go b/pricing/entity/product_price.go
similarity index 100%
rename from pricing/entity/entity.go
rename to pricing/entity/product_price.go
diff --git a/pricing/model/model.go b/pricing/model/product_price.go
similarity index 79%
rename from pricing/model/model.go
rename to pricing/model/product_price.go
index 852ecae..f21d2ac 100644
--- a/pricing/model/model.go
+++ b/pricing/model/product_price.go
@@ -1,7 +1,6 @@
 package pricing
 
 type ProductPriceModel struct {
-	// ID    int    `db:"id"`
 	PID   string `db:"pid"`
 	Price int    `db:"price"`
 }