diff --git a/internal/checker/builtin/any.go b/typecheck/builtin/any.go
similarity index 75%
rename from internal/checker/builtin/any.go
rename to typecheck/builtin/any.go
index 5f0352b..e56a886 100644
--- a/internal/checker/builtin/any.go
+++ b/typecheck/builtin/any.go
@@ -1,8 +1,6 @@
 package builtin
 
-import (
-	"git.xdrm.io/go/aicra/internal/checker"
-)
+import "git.xdrm.io/go/aicra/typecheck"
 
 // Any is a permissive type checker
 type Any struct{}
@@ -13,7 +11,7 @@ func NewAny() *Any {
 }
 
 // Checker returns the checker function
-func (Any) Checker(typeName string) checker.Checker {
+func (Any) Checker(typeName string) typecheck.Checker {
 	// nothing if type not handled
 	if typeName != "any" {
 		return nil
diff --git a/internal/checker/builtin/bool.go b/typecheck/builtin/bool.go
similarity index 78%
rename from internal/checker/builtin/bool.go
rename to typecheck/builtin/bool.go
index 90caa19..0fdc483 100644
--- a/internal/checker/builtin/bool.go
+++ b/typecheck/builtin/bool.go
@@ -1,6 +1,6 @@
 package builtin
 
-import "git.xdrm.io/go/aicra/internal/checker"
+import "git.xdrm.io/go/aicra/typecheck"
 
 // Bool checks if a value is a boolean
 type Bool struct{}
@@ -11,7 +11,7 @@ func NewBool() *Bool {
 }
 
 // Checker returns the checker function
-func (Bool) Checker(typeName string) checker.Checker {
+func (Bool) Checker(typeName string) typecheck.Checker {
 	// nothing if type not handled
 	if typeName != "bool" {
 		return nil
diff --git a/internal/checker/builtin/float64.go b/typecheck/builtin/float64.go
similarity index 79%
rename from internal/checker/builtin/float64.go
rename to typecheck/builtin/float64.go
index 9ff3dea..69c4948 100644
--- a/internal/checker/builtin/float64.go
+++ b/typecheck/builtin/float64.go
@@ -1,6 +1,6 @@
 package builtin
 
-import "git.xdrm.io/go/aicra/internal/checker"
+import "git.xdrm.io/go/aicra/typecheck"
 
 // Float64 checks if a value is a float64
 type Float64 struct{}
@@ -11,7 +11,7 @@ func NewFloat64() *Float64 {
 }
 
 // Checker returns the checker function
-func (Float64) Checker(typeName string) checker.Checker {
+func (Float64) Checker(typeName string) typecheck.Checker {
 	// nothing if type not handled
 	if typeName != "float64" && typeName != "float" {
 		return nil
diff --git a/internal/checker/builtin/string.go b/typecheck/builtin/string.go
similarity index 96%
rename from internal/checker/builtin/string.go
rename to typecheck/builtin/string.go
index e82e5ea..5bc9fc2 100644
--- a/internal/checker/builtin/string.go
+++ b/typecheck/builtin/string.go
@@ -4,7 +4,7 @@ import (
 	"regexp"
 	"strconv"
 
-	"git.xdrm.io/go/aicra/internal/checker"
+	"git.xdrm.io/go/aicra/typecheck"
 )
 
 var fixedLengthRegex = regexp.MustCompile(`^string\((\d+))$`)
@@ -19,7 +19,7 @@ func NewString() *String {
 }
 
 // Checker returns the checker function. Availables type names are : `string`, `string(length)` and `string(minLength, maxLength)`.
-func (s String) Checker(typeName string) checker.Checker {
+func (s String) Checker(typeName string) typecheck.Checker {
 	isSimpleString := typeName == "string"
 	fixedLengthMatches := fixedLengthRegex.FindStringSubmatch(typeName)
 	variableLengthMatches := variableLengthRegex.FindStringSubmatch(typeName)
diff --git a/internal/checker/set.go b/typecheck/set.go
similarity index 94%
rename from internal/checker/set.go
rename to typecheck/set.go
index c9d5090..b3a4a6f 100644
--- a/internal/checker/set.go
+++ b/typecheck/set.go
@@ -1,4 +1,4 @@
-package checker
+package typecheck
 
 // Set of type checkers
 type Set struct {
@@ -35,9 +35,8 @@ func (s *Set) Run(typeName string, value interface{}) error {
 		// check value
 		if checkerFunc(value) {
 			return nil
-		} else {
-			return ErrDoesNotMatch
 		}
+		return ErrDoesNotMatch
 	}
 
 	return ErrNoMatchingType
diff --git a/internal/checker/type.go b/typecheck/type.go
similarity index 96%
rename from internal/checker/type.go
rename to typecheck/type.go
index e5b0747..a278091 100644
--- a/internal/checker/type.go
+++ b/typecheck/type.go
@@ -1,4 +1,4 @@
-package checker
+package typecheck
 
 import "errors"