diff --git a/conv/conv.go b/conv/conv.go
index c7039c0..acb0f94 100644
--- a/conv/conv.go
+++ b/conv/conv.go
@@ -3,10 +3,30 @@ package conv
 
 import (
 	"strconv"
+)
 
-	"github.com/vividvilla/simplesessions"
+var (
+	// Error codes for store errors. This should match the codes
+	// defined in the /simplesessions package exactly.
+	ErrInvalidSession = &Err{code: 1, msg: "invalid session"}
+	ErrFieldNotFound  = &Err{code: 2, msg: "field not found"}
+	ErrAssertType     = &Err{code: 3, msg: "assertion failed"}
+	ErrNil            = &Err{code: 4, msg: "nil returned"}
 )
 
+type Err struct {
+	code int
+	msg  string
+}
+
+func (e *Err) Error() string {
+	return e.msg
+}
+
+func (e *Err) Code() int {
+	return e.code
+}
+
 // Int converts interface to integer.
 func Int(r interface{}, err error) (int, error) {
 	if err != nil {
@@ -29,10 +49,10 @@ func Int(r interface{}, err error) (int, error) {
 		n, err := strconv.ParseInt(r, 10, 0)
 		return int(n), err
 	case nil:
-		return 0, simplesessions.ErrNil
+		return 0, ErrNil
 	}
 
-	return 0, simplesessions.ErrAssertType
+	return 0, ErrAssertType
 }
 
 // Int64 converts interface to Int64.
@@ -53,10 +73,10 @@ func Int64(r interface{}, err error) (int64, error) {
 		n, err := strconv.ParseInt(r, 10, 64)
 		return n, err
 	case nil:
-		return 0, simplesessions.ErrNil
+		return 0, ErrNil
 	}
 
-	return 0, simplesessions.ErrAssertType
+	return 0, ErrAssertType
 }
 
 // UInt64 converts interface to UInt64.
@@ -70,12 +90,12 @@ func UInt64(r interface{}, err error) (uint64, error) {
 		return r, err
 	case int:
 		if r < 0 {
-			return 0, simplesessions.ErrAssertType
+			return 0, ErrAssertType
 		}
 		return uint64(r), nil
 	case int64:
 		if r < 0 {
-			return 0, simplesessions.ErrAssertType
+			return 0, ErrAssertType
 		}
 		return uint64(r), nil
 	case []byte:
@@ -85,10 +105,10 @@ func UInt64(r interface{}, err error) (uint64, error) {
 		n, err := strconv.ParseUint(r, 10, 64)
 		return n, err
 	case nil:
-		return 0, simplesessions.ErrNil
+		return 0, ErrNil
 	}
 
-	return 0, simplesessions.ErrAssertType
+	return 0, ErrAssertType
 }
 
 // Float64 converts interface to Float64.
@@ -106,9 +126,9 @@ func Float64(r interface{}, err error) (float64, error) {
 		n, err := strconv.ParseFloat(r, 64)
 		return n, err
 	case nil:
-		return 0, simplesessions.ErrNil
+		return 0, ErrNil
 	}
-	return 0, simplesessions.ErrAssertType
+	return 0, ErrAssertType
 }
 
 // String converts interface to String.
@@ -122,9 +142,9 @@ func String(r interface{}, err error) (string, error) {
 	case string:
 		return r, nil
 	case nil:
-		return "", simplesessions.ErrNil
+		return "", ErrNil
 	}
-	return "", simplesessions.ErrAssertType
+	return "", ErrAssertType
 }
 
 // Bytes converts interface to Bytes.
@@ -138,9 +158,9 @@ func Bytes(r interface{}, err error) ([]byte, error) {
 	case string:
 		return []byte(r), nil
 	case nil:
-		return nil, simplesessions.ErrNil
+		return nil, ErrNil
 	}
-	return nil, simplesessions.ErrAssertType
+	return nil, ErrAssertType
 }
 
 // Bool converts interface to Bool.
@@ -161,7 +181,7 @@ func Bool(r interface{}, err error) (bool, error) {
 	case string:
 		return strconv.ParseBool(r)
 	case nil:
-		return false, simplesessions.ErrNil
+		return false, ErrNil
 	}
-	return false, simplesessions.ErrAssertType
+	return false, ErrAssertType
 }
diff --git a/conv/conv_test.go b/conv/conv_test.go
index cf374f0..2ce0a9b 100644
--- a/conv/conv_test.go
+++ b/conv/conv_test.go
@@ -5,7 +5,6 @@ import (
 	"testing"
 
 	"github.com/stretchr/testify/assert"
-	"github.com/vividvilla/simplesessions"
 )
 
 var (
@@ -39,7 +38,7 @@ func TestInt(t *testing.T) {
 
 	// Test if ErrNil is returned if value is nil.
 	v, err = Int(nil, nil)
-	assert.Error(err, simplesessions.ErrNil)
+	assert.Error(err, ErrNil)
 	assert.Equal(0, v)
 
 	// Test if custom error sent is returned.
@@ -49,7 +48,7 @@ func TestInt(t *testing.T) {
 
 	// Test invalid assert error.
 	v, err = Int(10.1112, nil)
-	assert.Error(err, simplesessions.ErrAssertType)
+	assert.Error(err, ErrAssertType)
 	assert.Equal(0, v)
 }
 
@@ -75,7 +74,7 @@ func TestInt64(t *testing.T) {
 
 	// Test if ErrNil is returned if value is nil.
 	v, err = Int64(nil, nil)
-	assert.Error(err, simplesessions.ErrNil)
+	assert.Error(err, ErrNil)
 	assert.Equal(int64(0), v)
 
 	// Test if custom error sent is returned.
@@ -85,7 +84,7 @@ func TestInt64(t *testing.T) {
 
 	// Test invalid assert error.
 	v, err = Int64(10.1112, nil)
-	assert.Error(err, simplesessions.ErrAssertType)
+	assert.Error(err, ErrAssertType)
 	assert.Equal(int64(0), v)
 }
 
@@ -111,7 +110,7 @@ func TestUInt64(t *testing.T) {
 
 	// Test if ErrNil is returned if value is nil.
 	v, err = UInt64(nil, nil)
-	assert.Error(err, simplesessions.ErrNil)
+	assert.Error(err, ErrNil)
 	assert.Equal(uint64(0), v)
 
 	// Test if custom error sent is returned.
@@ -121,7 +120,7 @@ func TestUInt64(t *testing.T) {
 
 	// Test invalid assert error.
 	v, err = UInt64(10.1112, nil)
-	assert.Error(err, simplesessions.ErrAssertType)
+	assert.Error(err, ErrAssertType)
 	assert.Equal(uint64(0), v)
 }
 
@@ -147,7 +146,7 @@ func TestFloat64(t *testing.T) {
 
 	// Test if ErrNil is returned if value is nil.
 	v, err = Float64(nil, nil)
-	assert.Error(err, simplesessions.ErrNil)
+	assert.Error(err, ErrNil)
 	assert.Equal(float64(0), v)
 
 	// Test if custom error sent is returned.
@@ -157,7 +156,7 @@ func TestFloat64(t *testing.T) {
 
 	// Test invalid assert error.
 	v, err = Float64("abc", nil)
-	assert.Error(err, simplesessions.ErrAssertType)
+	assert.Error(err, ErrAssertType)
 	assert.Equal(float64(0), v)
 }
 
@@ -179,7 +178,7 @@ func TestString(t *testing.T) {
 
 	// Test if ErrNil is returned if value is nil.
 	v, err = String(nil, nil)
-	assert.Error(err, simplesessions.ErrNil)
+	assert.Error(err, ErrNil)
 	assert.Equal("", v)
 
 	// Test if custom error sent is returned.
@@ -189,7 +188,7 @@ func TestString(t *testing.T) {
 
 	// Test invalid assert error.
 	v, err = String(10.1112, nil)
-	assert.Error(err, simplesessions.ErrAssertType)
+	assert.Error(err, ErrAssertType)
 	assert.Equal("", v)
 }
 
@@ -211,7 +210,7 @@ func TestBytes(t *testing.T) {
 
 	// Test if ErrNil is returned if value is nil.
 	v, err = Bytes(nil, nil)
-	assert.Error(err, simplesessions.ErrNil)
+	assert.Error(err, ErrNil)
 	assert.Equal([]byte(nil), v)
 
 	// Test if custom error sent is returned.
@@ -221,7 +220,7 @@ func TestBytes(t *testing.T) {
 
 	// Test invalid assert error.
 	v, err = Bytes(10.1112, nil)
-	assert.Error(err, simplesessions.ErrAssertType)
+	assert.Error(err, ErrAssertType)
 	assert.Equal([]byte(nil), v)
 }
 
@@ -270,7 +269,7 @@ func TestBool(t *testing.T) {
 
 	// Test if ErrNil is returned if value is nil.
 	v, err = Bool(nil, nil)
-	assert.Error(err, simplesessions.ErrNil)
+	assert.Error(err, ErrNil)
 	assert.Equal(false, v)
 
 	// Test if custom error sent is returned.
@@ -280,6 +279,6 @@ func TestBool(t *testing.T) {
 
 	// Test invalid assert error.
 	v, err = Bool(10.1112, nil)
-	assert.Error(err, simplesessions.ErrAssertType)
+	assert.Error(err, ErrAssertType)
 	assert.Equal(false, v)
 }
diff --git a/go.work b/go.work
index a0da523..d814b3d 100644
--- a/go.work
+++ b/go.work
@@ -2,6 +2,7 @@ go 1.18
 
 use (
 	.
+	./conv
 	./stores/goredis
 	./stores/redis
 	./stores/securecookie