diff --git a/pkg/package/package.go b/pkg/package/package.go
index 434a8c5c..83ab6197 100644
--- a/pkg/package/package.go
+++ b/pkg/package/package.go
@@ -17,6 +17,7 @@ package pkg
 
 import (
 	"fmt"
+	"path/filepath"
 
 	"github.com/crillab/gophersat/bf"
 	version "github.com/hashicorp/go-version"
@@ -57,6 +58,7 @@ type Package interface {
 
 	SetPath(string)
 	GetPath() string
+	Rel(string) string
 }
 
 type PackageSet interface {
@@ -122,6 +124,11 @@ func (p *DefaultPackage) GetPath() string {
 	return p.Path
 }
 
+func (p *DefaultPackage) Rel(s string) string {
+	return filepath.Join(p.GetPath(), s)
+
+}
+
 func (p *DefaultPackage) SetPath(s string) {
 	p.Path = s
 }