diff --git a/bytes/seekable/seekable_test.go b/bytes/seekable/seekable_test.go
index 98d97f9..15d49bd 100644
--- a/bytes/seekable/seekable_test.go
+++ b/bytes/seekable/seekable_test.go
@@ -4,40 +4,50 @@ import (
 	"bytes"
 	"net/http"
 	"testing"
-
-	"github.com/stretchr/testify/assert"
 )
 
+func assertEqual(t *testing.T, a, b interface{}) {
+	if a != b {
+		t.Fatal("assertEqual:", a, b)
+	}
+}
+
+func assertNoError(t *testing.T, err error) {
+	if err != nil {
+		t.Fatal("assertNoError:", err)
+	}
+}
+
 func TestSeekable_EOFIfReqAlreadyParsed(t *testing.T) {
 	body := "a=1"
 	req, err := http.NewRequest("POST", "/a", bytes.NewBufferString(body))
-	assert.NoError(t, err)
+	assertNoError(t, err)
 	req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
 	req.Header.Set("Content-Length", "3")
 	req.ParseForm()
 	_, err = New(req)
-	assert.Equal(t, err.Error(), "EOF")
+	assertEqual(t, err.Error(), "EOF")
 }
 
 func TestSeekable_WorkaroundForEOF(t *testing.T) {
 	body := "a=1"
 	req, err := http.NewRequest("POST", "/a", bytes.NewBufferString(body))
-	assert.NoError(t, err)
+	assertNoError(t, err)
 	req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
 	req.Header.Set("Content-Length", "3")
 	_, _ = New(req)
 	req.ParseForm()
-	assert.Equal(t, req.FormValue("a"), "1")
+	assertEqual(t, req.FormValue("a"), "1")
 	_, err = New(req)
-	assert.NoError(t, err)
+	assertNoError(t, err)
 }
 
 func TestSeekable(t *testing.T) {
 	body := "a=1"
 	req, err := http.NewRequest("POST", "/a", bytes.NewBufferString(body))
-	assert.NoError(t, err)
+	assertNoError(t, err)
 	req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
 	req.Header.Set("Content-Length", "3")
 	_, err = New(req)
-	assert.NoError(t, err)
+	assertNoError(t, err)
 }