diff --git a/client.go b/client.go
index 3f6e9ef..e97ab2d 100644
--- a/client.go
+++ b/client.go
@@ -2,7 +2,6 @@ package httpaux
 
 import (
 	"io"
-	"io/ioutil"
 	"net/http"
 )
 
@@ -20,7 +19,7 @@ var _ Client = (*http.Client)(nil)
 // does nothing.
 func Cleanup(r *http.Response) {
 	if r != nil && r.Body != nil {
-		io.Copy(ioutil.Discard, r.Body)
+		io.Copy(io.Discard, r.Body)
 		r.Body.Close()
 	}
 }
diff --git a/client/middleware_test.go b/client/middleware_test.go
index 964c706..b1a5b10 100644
--- a/client/middleware_test.go
+++ b/client/middleware_test.go
@@ -3,7 +3,6 @@ package client
 import (
 	"errors"
 	"io"
-	"io/ioutil"
 	"net/http"
 	"net/http/httptest"
 	"strconv"
@@ -77,7 +76,7 @@ func (suite *ChainTestSuite) assertRequest(expectedOrder []int, client httpaux.C
 	suite.Require().NoError(err)
 
 	defer response.Body.Close()
-	io.Copy(ioutil.Discard, response.Body)
+	io.Copy(io.Discard, response.Body)
 	suite.Equal(expectedOrder, suite.order, "the decorators did not run in the expected order")
 	suite.Equal(299, response.StatusCode, "the test server was not invoked")
 }
diff --git a/erraux/encoder_test.go b/erraux/encoder_test.go
index 9b8ab58..19a8700 100644
--- a/erraux/encoder_test.go
+++ b/erraux/encoder_test.go
@@ -3,7 +3,7 @@ package erraux
 import (
 	"context"
 	"errors"
-	"io/ioutil"
+	"io"
 	"net/http"
 	"net/http/httptest"
 	"testing"
@@ -29,7 +29,7 @@ func (suite *EncoderTestSuite) result(rw *httptest.ResponseRecorder) (statusCode
 	h = result.Header
 	suite.Equal("application/json", h.Get("Content-Type"))
 
-	b, err := ioutil.ReadAll(result.Body)
+	b, err := io.ReadAll(result.Body)
 	suite.Require().NoError(err)
 	body = string(b)
 
diff --git a/gate/middleware_test.go b/gate/middleware_test.go
index 998ed63..d936220 100644
--- a/gate/middleware_test.go
+++ b/gate/middleware_test.go
@@ -3,7 +3,6 @@ package gate
 import (
 	"errors"
 	"io"
-	"io/ioutil"
 	"net/http"
 	"net/http/httptest"
 	"testing"
@@ -174,7 +173,7 @@ func (suite *ClientTestSuite) TestDefaultOpen() {
 		suite.NoError(err)
 		suite.Require().NotNil(response)
 		suite.Equal(277, response.StatusCode)
-		io.Copy(ioutil.Discard, response.Body)
+		io.Copy(io.Discard, response.Body)
 		response.Body.Close()
 	})
 
@@ -185,7 +184,7 @@ func (suite *ClientTestSuite) TestDefaultOpen() {
 		suite.NoError(err)
 		suite.Require().NotNil(response)
 		suite.Equal(277, response.StatusCode)
-		io.Copy(ioutil.Discard, response.Body)
+		io.Copy(io.Discard, response.Body)
 		response.Body.Close()
 	})
 }
@@ -198,7 +197,7 @@ func (suite *ClientTestSuite) TestDefaultClosed() {
 		response, err := suite.checkRoundTripper(rt)
 
 		if !suite.Nil(response) {
-			io.Copy(ioutil.Discard, response.Body)
+			io.Copy(io.Discard, response.Body)
 			response.Body.Close()
 		}
 
@@ -210,7 +209,7 @@ func (suite *ClientTestSuite) TestDefaultClosed() {
 		response, err := suite.checkRoundTripper(rt)
 
 		if !suite.Nil(response) {
-			io.Copy(ioutil.Discard, response.Body)
+			io.Copy(io.Discard, response.Body)
 			response.Body.Close()
 		}
 
@@ -229,7 +228,7 @@ func (suite *ClientTestSuite) TestCustomOpen() {
 		suite.NoError(err)
 		suite.Require().NotNil(response)
 		suite.Equal(277, response.StatusCode)
-		io.Copy(ioutil.Discard, response.Body)
+		io.Copy(io.Discard, response.Body)
 		response.Body.Close()
 	})
 
@@ -243,7 +242,7 @@ func (suite *ClientTestSuite) TestCustomOpen() {
 		suite.NoError(err)
 		suite.Require().NotNil(response)
 		suite.Equal(277, response.StatusCode)
-		io.Copy(ioutil.Discard, response.Body)
+		io.Copy(io.Discard, response.Body)
 		response.Body.Close()
 	})
 }
@@ -259,7 +258,7 @@ func (suite *ClientTestSuite) TestCustomClosed() {
 		response, err := suite.checkRoundTripper(rt)
 
 		if !suite.Nil(response) {
-			io.Copy(ioutil.Discard, response.Body)
+			io.Copy(io.Discard, response.Body)
 			response.Body.Close()
 		}
 
@@ -274,7 +273,7 @@ func (suite *ClientTestSuite) TestCustomClosed() {
 		response, err := suite.checkRoundTripper(rt)
 
 		if !suite.Nil(response) {
-			io.Copy(ioutil.Discard, response.Body)
+			io.Copy(io.Discard, response.Body)
 			response.Body.Close()
 		}
 
diff --git a/httpmock/body_test.go b/httpmock/body_test.go
index deaaddf..0ccaebf 100644
--- a/httpmock/body_test.go
+++ b/httpmock/body_test.go
@@ -4,7 +4,6 @@ import (
 	"bytes"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"testing"
 
 	"github.com/stretchr/testify/suite"
@@ -17,7 +16,7 @@ type BodyReadCloserTestSuite struct {
 func (suite *BodyReadCloserTestSuite) testBodyReadCloser(body *BodyReadCloser, expected []byte) {
 	suite.Require().NotNil(body)
 
-	actual, err := ioutil.ReadAll(body)
+	actual, err := io.ReadAll(body)
 	suite.Equal(expected, actual)
 	suite.NoError(err)
 
@@ -58,7 +57,7 @@ func (suite *BodyReadCloserTestSuite) TestBodyf() {
 }
 
 func (suite *BodyReadCloserTestSuite) TestNopCloser() {
-	body := ioutil.NopCloser(
+	body := io.NopCloser(
 		bytes.NewBufferString("this body doesn't implement Closeable"),
 	)
 
diff --git a/httpmock/requestChecker_test.go b/httpmock/requestChecker_test.go
index 775f260..3e02fca 100644
--- a/httpmock/requestChecker_test.go
+++ b/httpmock/requestChecker_test.go
@@ -3,7 +3,6 @@ package httpmock
 import (
 	"errors"
 	"io"
-	"io/ioutil"
 	"net/http"
 	"net/url"
 	"strconv"
@@ -370,7 +369,7 @@ func (suite *RequestCheckerTestSuite) TestBody() {
 		}()
 
 		request := &http.Request{
-			Body: ioutil.NopCloser(reader),
+			Body: io.NopCloser(reader),
 		}
 
 		t := wrapTestingT(suite.T())
@@ -462,7 +461,7 @@ func (suite *RequestCheckerTestSuite) TestBodyJSON() {
 		}()
 
 		request := &http.Request{
-			Body: ioutil.NopCloser(reader),
+			Body: io.NopCloser(reader),
 		}
 
 		t := wrapTestingT(suite.T())
diff --git a/httpmock/roundTripper_test.go b/httpmock/roundTripper_test.go
index 1c1f278..ee8d795 100644
--- a/httpmock/roundTripper_test.go
+++ b/httpmock/roundTripper_test.go
@@ -4,7 +4,6 @@ package httpmock
 import (
 	"errors"
 	"io"
-	"io/ioutil"
 	"net/http"
 	"net/http/httptest"
 	"net/url"
@@ -32,7 +31,7 @@ func (suite *RoundTripperSuite) assertResponse(r *http.Response) {
 
 	if suite.NotNil(r.Body) {
 		defer r.Body.Close()
-		b, err := ioutil.ReadAll(r.Body)
+		b, err := io.ReadAll(r.Body)
 		if suite.NoError(err) {
 			suite.Equal("RoundTripperSuite", string(b))
 		}
diff --git a/retry/client_test.go b/retry/client_test.go
index 7229279..cbea9ae 100644
--- a/retry/client_test.go
+++ b/retry/client_test.go
@@ -6,7 +6,6 @@ import (
 	"context"
 	"errors"
 	"io"
-	"io/ioutil"
 	"net/http"
 	"net/http/httptest"
 	"strconv"
@@ -86,7 +85,7 @@ func (suite *ClientTestSuite) handler(rw http.ResponseWriter, actual *http.Reque
 	suite.Equal(suite.expected.URL.Path, actual.URL.Path)
 	suite.Equal(int64(len(suite.expectedBody)), actual.ContentLength)
 
-	b, err := ioutil.ReadAll(actual.Body)
+	b, err := io.ReadAll(actual.Body)
 	suite.NoError(err)
 	suite.Equal(suite.expectedBody, string(b))
 
@@ -105,7 +104,7 @@ func (suite *ClientTestSuite) assertResponse(r *http.Response) {
 
 	suite.Require().NotNil(r.Body)
 	defer r.Body.Close()
-	b, err := ioutil.ReadAll(r.Body)
+	b, err := io.ReadAll(r.Body)
 	suite.NoError(err)
 	suite.Equal("ClientTestSuite", string(b))
 }
diff --git a/roundtrip/middleware_test.go b/roundtrip/middleware_test.go
index 0ac76c3..ef80609 100644
--- a/roundtrip/middleware_test.go
+++ b/roundtrip/middleware_test.go
@@ -3,7 +3,6 @@ package roundtrip
 import (
 	"errors"
 	"io"
-	"io/ioutil"
 	"net/http"
 	"net/http/httptest"
 	"strconv"
@@ -80,7 +79,7 @@ func (suite *ChainTestSuite) assertRequest(expectedOrder []int, transport http.R
 	suite.Require().NoError(err)
 
 	defer response.Body.Close()
-	io.Copy(ioutil.Discard, response.Body)
+	io.Copy(io.Discard, response.Body)
 	suite.Equal(expectedOrder, suite.order, "the decorators did not run in the expected order")
 	suite.Equal(299, response.StatusCode, "the test server was not invoked")
 }