diff --git a/handler/openapi_validator.go b/handler/openapi_validator.go
index e635a875a..41248b8c5 100644
--- a/handler/openapi_validator.go
+++ b/handler/openapi_validator.go
@@ -5,9 +5,12 @@ import (
 	"io/ioutil"
 	"net/http"
 	"os"
+	"path/filepath"
 
-	"github.com/avenga/couper/config"
+	"github.com/getkin/kin-openapi/openapi3"
 	"github.com/getkin/kin-openapi/openapi3filter"
+
+	"github.com/avenga/couper/config"
 )
 
 type OpenAPIValidatorFactory struct {
@@ -24,11 +27,29 @@ func NewOpenAPIValidatorFactory(openapi *config.OpenAPI) (*OpenAPIValidatorFacto
 	if err != nil {
 		return nil, err
 	}
-	router := openapi3filter.NewRouter()
-	err = router.AddSwaggerFromFile(dir + "/" + openapi.File)
+
+	bytes, err := ioutil.ReadFile(filepath.Join(dir, openapi.File))
+	if err != nil {
+		return nil, err
+	}
+	return NewOpenAPIValidatorFactoryFromBytes(openapi, bytes)
+}
+
+func NewOpenAPIValidatorFactoryFromBytes(openapi *config.OpenAPI, bytes []byte) (*OpenAPIValidatorFactory, error) {
+	if openapi == nil || bytes == nil {
+		return nil, nil
+	}
+
+	swagger, err := openapi3.NewSwaggerLoader().LoadSwaggerFromData(bytes)
 	if err != nil {
 		return nil, err
 	}
+
+	router := openapi3filter.NewRouter()
+	if err = router.AddSwagger(swagger); err != nil {
+		return nil, err
+	}
+
 	return &OpenAPIValidatorFactory{
 		router:                   router,
 		ignoreRequestViolations:  openapi.IgnoreRequestViolations,
diff --git a/handler/proxy.go b/handler/proxy.go
index c1a515b88..8a2767155 100644
--- a/handler/proxy.go
+++ b/handler/proxy.go
@@ -11,7 +11,6 @@ import (
 	"net"
 	"net/http"
 	"net/url"
-	"os"
 	"regexp"
 	"strconv"
 	"strings"
diff --git a/handler/proxy_test.go b/handler/proxy_test.go
index 3cc18e819..62cc6bc13 100644
--- a/handler/proxy_test.go
+++ b/handler/proxy_test.go
@@ -5,10 +5,8 @@ import (
 	"compress/gzip"
 	"context"
 	"io"
-	"io/ioutil"
 	"net/http"
 	"net/http/httptest"
-	"os"
 	"reflect"
 	"strings"
 	"testing"
@@ -425,9 +423,7 @@ paths:
 	helper.Must(err)
 
 	openapiYAML := &bytes.Buffer{}
-	openapiYAMLTemplate.Execute(openapiYAML, map[string]string{"url": origin.URL})
-	helper.Must(ioutil.WriteFile("testdata/upstream.yaml", openapiYAML.Bytes(), 0644))
-	defer helper.Must(os.Remove("testdata/upstream.yaml"))
+	helper.Must(openapiYAMLTemplate.Execute(openapiYAML, map[string]string{"url": origin.URL}))
 
 	tests := []struct {
 		name               string
@@ -482,11 +478,14 @@ paths:
 	for _, tt := range tests {
 		t.Run(tt.name, func(subT *testing.T) {
 			logger, hook := logrustest.NewNullLogger()
-			openapiValidatorFactory, err := handler.NewOpenAPIValidatorFactory(tt.openapi)
+			openapiValidatorFactory, err := handler.NewOpenAPIValidatorFactoryFromBytes(tt.openapi, openapiYAML.Bytes())
 			if err != nil {
 				subT.Fatal(err)
 			}
-			p, err := handler.NewProxy(&handler.ProxyOptions{Origin: origin.URL, OpenAPI: openapiValidatorFactory}, logger.WithContext(context.Background()), nil, eval.NewENVContext(nil))
+			content := helper.NewProxyContext(`
+				origin = "` + origin.URL + `"
+			`)
+			p, err := handler.NewProxy(&handler.ProxyOptions{Context: content, OpenAPI: openapiValidatorFactory}, logger.WithContext(context.Background()), nil, eval.NewENVContext(nil))
 			if err != nil {
 				subT.Fatal(err)
 			}