diff --git a/tfexec/cmd.go b/tfexec/cmd.go
index 5a3e38e2..f5457769 100644
--- a/tfexec/cmd.go
+++ b/tfexec/cmd.go
@@ -107,13 +107,13 @@ func (tf *Terraform) runTerraformCmd(cmd *exec.Cmd) error {
 
 	stdout := tf.stdout
 	if cmd.Stdout != nil {
-		stdout = io.MultiWriter(cmd.Stdout, stdout)
+		stdout = io.MultiWriter(stdout, cmd.Stdout)
 	}
 	cmd.Stdout = stdout
 
 	stderr := io.MultiWriter(&errBuf, tf.stderr)
 	if cmd.Stderr != nil {
-		stderr = io.MultiWriter(cmd.Stderr, stderr)
+		stderr = io.MultiWriter(stderr, cmd.Stderr)
 	}
 	cmd.Stderr = stderr
 
diff --git a/tfexec/internal/e2etest/util_test.go b/tfexec/internal/e2etest/util_test.go
index faf50454..0862b4a8 100644
--- a/tfexec/internal/e2etest/util_test.go
+++ b/tfexec/internal/e2etest/util_test.go
@@ -8,6 +8,7 @@ import (
 	"io/ioutil"
 	"os"
 	"path/filepath"
+	"strings"
 	"testing"
 
 	"github.com/hashicorp/go-version"
@@ -62,7 +63,7 @@ func runTestVersions(t *testing.T, versions []string, fixtureName string, cb fun
 				}
 			}
 
-			var stdouterr bytes.Buffer
+			var stdouterr strings.Builder
 			tf.SetStdout(&stdouterr)
 			tf.SetStderr(&stdouterr)