diff --git a/bundle.go b/bundle.go
index 91fb36f..9f43c33 100644
--- a/bundle.go
+++ b/bundle.go
@@ -15,6 +15,8 @@ import (
 type Bundle interface {
 	// Data returns the contents of the bundle's bundle.yaml file.
 	Data() *BundleData
+	// BundleBytes returns the raw bytes content of a bundle
+	BundleBytes() []byte
 	// ReadMe returns the contents of the bundle's README.md file.
 	ReadMe() string
 	// ContainsOverlays returns true if the bundle contains any overlays.
diff --git a/bundle_test.go b/bundle_test.go
index 0180b95..e3d35da 100644
--- a/bundle_test.go
+++ b/bundle_test.go
@@ -4,6 +4,9 @@
 package charm_test
 
 import (
+	"os"
+	"path/filepath"
+
 	"github.com/juju/testing"
 	jc "github.com/juju/testing/checkers"
 	gc "gopkg.in/check.v1"
@@ -23,7 +26,7 @@ func (*BundleSuite) TestReadBundleDir(c *gc.C) {
 	c.Assert(err, gc.IsNil)
 	c.Assert(b.ContainsOverlays(), jc.IsFalse)
 	c.Assert(b, gc.FitsTypeOf, (*charm.BundleDir)(nil))
-	checkWordpressBundle(c, b, path)
+	checkWordpressBundle(c, b, path, "wordpress-simple")
 }
 
 func (*BundleSuite) TestReadMultiDocBundleDir(c *gc.C) {
@@ -32,7 +35,7 @@ func (*BundleSuite) TestReadMultiDocBundleDir(c *gc.C) {
 	c.Assert(err, gc.IsNil)
 	c.Assert(b.ContainsOverlays(), jc.IsTrue)
 	c.Assert(b, gc.FitsTypeOf, (*charm.BundleDir)(nil))
-	checkWordpressBundle(c, b, path)
+	checkWordpressBundle(c, b, path, "wordpress-simple-multidoc")
 }
 
 func (*BundleSuite) TestReadBundleArchive(c *gc.C) {
@@ -41,7 +44,7 @@ func (*BundleSuite) TestReadBundleArchive(c *gc.C) {
 	c.Assert(err, gc.IsNil)
 	c.Assert(b.ContainsOverlays(), jc.IsFalse)
 	c.Assert(b, gc.FitsTypeOf, (*charm.BundleDir)(nil))
-	checkWordpressBundle(c, b, path)
+	checkWordpressBundle(c, b, path, "wordpress-simple")
 }
 
 func (*BundleSuite) TestReadMultiDocBundleArchive(c *gc.C) {
@@ -50,10 +53,10 @@ func (*BundleSuite) TestReadMultiDocBundleArchive(c *gc.C) {
 	c.Assert(err, gc.IsNil)
 	c.Assert(b.ContainsOverlays(), jc.IsTrue)
 	c.Assert(b, gc.FitsTypeOf, (*charm.BundleDir)(nil))
-	checkWordpressBundle(c, b, path)
+	checkWordpressBundle(c, b, path, "wordpress-simple-multidoc")
 }
 
-func checkWordpressBundle(c *gc.C, b charm.Bundle, path string) {
+func checkWordpressBundle(c *gc.C, b charm.Bundle, path string, bundleName string) {
 	// Load the charms required by the bundle.
 	wordpressCharm := readCharmDir(c, "wordpress")
 	mysqlCharm := readCharmDir(c, "mysql")
@@ -87,6 +90,11 @@ func checkWordpressBundle(c *gc.C, b charm.Bundle, path string) {
 	case *charm.BundleDir:
 		c.Assert(b.Path, gc.Equals, path)
 	}
+
+	bundlePath := filepath.Join("internal/test-charm-repo/bundle", bundleName, "bundle.yaml")
+	raw, err := os.ReadFile(bundlePath)
+	c.Assert(err, jc.ErrorIsNil)
+	c.Assert(string(b.BundleBytes()), gc.Equals, string(raw))
 }
 
 func verifyOk(string) error {
diff --git a/bundlearchive.go b/bundlearchive.go
index 4bb2eea..4a2feda 100644
--- a/bundlearchive.go
+++ b/bundlearchive.go
@@ -6,7 +6,6 @@ package charm
 import (
 	"bytes"
 	"io"
-	"io/ioutil"
 
 	ziputil "github.com/juju/utils/v4/zip"
 )
@@ -14,9 +13,10 @@ import (
 type BundleArchive struct {
 	zopen zipOpener
 
-	Path   string
-	data   *BundleData
-	readMe string
+	Path        string
+	data        *BundleData
+	bundleBytes []byte
+	readMe      string
 
 	containsOverlays bool
 }
@@ -61,7 +61,12 @@ func readBundleArchive(zopen zipOpener) (*BundleArchive, error) {
 	if err != nil {
 		return nil, err
 	}
-	a.data, a.containsOverlays, err = readBaseFromMultidocBundle(reader)
+	b, err := io.ReadAll(reader)
+	if err != nil {
+		return nil, err
+	}
+	a.bundleBytes = b
+	a.data, a.containsOverlays, err = readBaseFromMultidocBundle(b)
 	reader.Close()
 	if err != nil {
 		return nil, err
@@ -70,7 +75,7 @@ func readBundleArchive(zopen zipOpener) (*BundleArchive, error) {
 	if err != nil {
 		return nil, err
 	}
-	readMe, err := ioutil.ReadAll(reader)
+	readMe, err := io.ReadAll(reader)
 	if err != nil {
 		return nil, err
 	}
@@ -83,6 +88,11 @@ func (a *BundleArchive) Data() *BundleData {
 	return a.data
 }
 
+// BundleBytes implements Bundle.BundleBytes.
+func (a *BundleArchive) BundleBytes() []byte {
+	return a.bundleBytes
+}
+
 // ReadMe implements Bundle.ReadMe.
 func (a *BundleArchive) ReadMe() string {
 	return a.readMe
diff --git a/bundlearchive_test.go b/bundlearchive_test.go
index e678276..f6d63e2 100644
--- a/bundlearchive_test.go
+++ b/bundlearchive_test.go
@@ -5,7 +5,6 @@ package charm_test
 
 import (
 	"fmt"
-	"io/ioutil"
 	"os"
 	"path/filepath"
 
@@ -21,35 +20,37 @@ type BundleArchiveSuite struct {
 	archivePath string
 }
 
+const bundleName = "wordpress-simple"
+
 func (s *BundleArchiveSuite) SetUpSuite(c *gc.C) {
-	s.archivePath = archivePath(c, readBundleDir(c, "wordpress-simple"))
+	s.archivePath = archivePath(c, readBundleDir(c, bundleName))
 }
 
 func (s *BundleArchiveSuite) TestReadBundleArchive(c *gc.C) {
 	archive, err := charm.ReadBundleArchive(s.archivePath)
 	c.Assert(err, gc.IsNil)
-	checkWordpressBundle(c, archive, s.archivePath)
+	checkWordpressBundle(c, archive, s.archivePath, bundleName)
 }
 
 func (s *BundleArchiveSuite) TestReadBundleArchiveBytes(c *gc.C) {
-	data, err := ioutil.ReadFile(s.archivePath)
+	data, err := os.ReadFile(s.archivePath)
 	c.Assert(err, gc.IsNil)
 
 	archive, err := charm.ReadBundleArchiveBytes(data)
 	c.Assert(err, gc.IsNil)
 	c.Assert(archive.ContainsOverlays(), jc.IsFalse)
-	checkWordpressBundle(c, archive, "")
+	checkWordpressBundle(c, archive, "", bundleName)
 }
 
 func (s *BundleArchiveSuite) TestReadMultiDocBundleArchiveBytes(c *gc.C) {
 	path := archivePath(c, readBundleDir(c, "wordpress-simple-multidoc"))
-	data, err := ioutil.ReadFile(path)
+	data, err := os.ReadFile(path)
 	c.Assert(err, gc.IsNil)
 
 	archive, err := charm.ReadBundleArchiveBytes(data)
 	c.Assert(err, gc.IsNil)
 	c.Assert(archive.ContainsOverlays(), jc.IsTrue)
-	checkWordpressBundle(c, archive, "")
+	checkWordpressBundle(c, archive, "", "wordpress-simple-multidoc")
 }
 
 func (s *BundleArchiveSuite) TestReadBundleArchiveFromReader(c *gc.C) {
@@ -61,7 +62,7 @@ func (s *BundleArchiveSuite) TestReadBundleArchiveFromReader(c *gc.C) {
 
 	archive, err := charm.ReadBundleArchiveFromReader(f, info.Size())
 	c.Assert(err, gc.IsNil)
-	checkWordpressBundle(c, archive, "")
+	checkWordpressBundle(c, archive, "", bundleName)
 }
 
 func (s *BundleArchiveSuite) TestReadBundleArchiveWithoutBundleYAML(c *gc.C) {
diff --git a/bundledata.go b/bundledata.go
index ebf3cb4..89d28a3 100644
--- a/bundledata.go
+++ b/bundledata.go
@@ -49,12 +49,10 @@ type BundleData struct {
 	// Series holds the default series to use when
 	// the bundle deploys applications. A series defined for an application
 	// takes precedence.
-	// Series and Base cannot be mixed.
 	Series string `bson:",omitempty" json:",omitempty" yaml:",omitempty"`
 
 	// Base holds the default base to use when the bundle deploys
 	// applications. A base defined for an application takes precedence.
-	// Series and Base cannot be mixed.
 	DefaultBase string `bson:"default-base,omitempty" json:"default-base,omitempty" yaml:"default-base,omitempty"`
 
 	// Relations holds a slice of 2-element slices,
@@ -104,11 +102,9 @@ type ApplicationSpec struct {
 	Revision *int `bson:"revision,omitempty" yaml:"revision,omitempty" json:"revision,omitempty"`
 
 	// Series is the series to use when deploying the application.
-	// Series and Base cannot be mixed.
 	Series string `bson:",omitempty" yaml:",omitempty" json:",omitempty"`
 
 	// Base is the base to use when deploying the application.
-	// Series and Base cannot be mixed.
 	Base string `bson:",omitempty" yaml:",omitempty" json:",omitempty"`
 
 	// Resources is the set of resource revisions to deploy for the
@@ -355,7 +351,11 @@ type OfferSpec struct {
 // The returned data is not verified - call Verify to ensure
 // that it is OK.
 func ReadBundleData(r io.Reader) (*BundleData, error) {
-	bd, _, err := readBaseFromMultidocBundle(r)
+	b, err := io.ReadAll(r)
+	if err != nil {
+		return nil, err
+	}
+	bd, _, err := readBaseFromMultidocBundle(b)
 	if err != nil {
 		return nil, err
 	}
@@ -370,8 +370,8 @@ func ReadBundleData(r io.Reader) (*BundleData, error) {
 //
 // Clients that are interested in reading multi-doc bundle data should use the
 // new helpers: LocalBundleDataSource and StreamBundleDataSource.
-func readBaseFromMultidocBundle(r io.Reader) (*BundleData, bool, error) {
-	parts, err := parseBundleParts(r)
+func readBaseFromMultidocBundle(b []byte) (*BundleData, bool, error) {
+	parts, err := parseBundleParts(b)
 	if err != nil {
 		return nil, false, err
 	}
diff --git a/bundledatasrc.go b/bundledatasrc.go
index a7b9702..2440613 100644
--- a/bundledatasrc.go
+++ b/bundledatasrc.go
@@ -6,7 +6,6 @@ package charm
 import (
 	"bytes"
 	"io"
-	"io/ioutil"
 	"os"
 	"path/filepath"
 	"strings"
@@ -55,19 +54,25 @@ type BundleDataPart struct {
 // list of composable parts.
 type BundleDataSource interface {
 	Parts() []*BundleDataPart
+	BundleBytes() []byte
 	BasePath() string
 	ResolveInclude(path string) ([]byte, error)
 }
 
 type resolvedBundleDataSource struct {
-	basePath string
-	parts    []*BundleDataPart
+	basePath    string
+	bundleBytes []byte
+	parts       []*BundleDataPart
 }
 
 func (s *resolvedBundleDataSource) Parts() []*BundleDataPart {
 	return s.parts
 }
 
+func (s *resolvedBundleDataSource) BundleBytes() []byte {
+	return s.bundleBytes
+}
+
 func (s *resolvedBundleDataSource) BasePath() string {
 	return s.basePath
 }
@@ -95,7 +100,7 @@ func (s *resolvedBundleDataSource) ResolveInclude(path string) ([]byte, error) {
 		return nil, errors.Errorf("include path %q resolves to a folder", absPath)
 	}
 
-	data, err := ioutil.ReadFile(absPath)
+	data, err := os.ReadFile(absPath)
 	if err != nil {
 		return nil, errors.Annotatef(err, "reading include file at %q", absPath)
 	}
@@ -131,15 +136,20 @@ func LocalBundleDataSource(path string) (BundleDataSource, error) {
 	}
 	defer func() { _ = f.Close() }()
 
-	parts, pErr := parseBundleParts(f)
+	b, err := io.ReadAll(f)
+	if err != nil {
+		return nil, err
+	}
+	parts, pErr := parseBundleParts(b)
 	if pErr == nil {
 		absPath, err := filepath.Abs(path)
 		if err != nil {
 			return nil, errors.Annotatef(err, "resolve absolute path to %s", path)
 		}
 		return &resolvedBundleDataSource{
-			basePath: filepath.Dir(absPath),
-			parts:    parts,
+			basePath:    filepath.Dir(absPath),
+			parts:       parts,
+			bundleBytes: b,
 		}, nil
 	}
 
@@ -159,10 +169,15 @@ func LocalBundleDataSource(path string) (BundleDataSource, error) {
 	}
 	defer func() { _ = r.Close() }()
 
-	if parts, pErr = parseBundleParts(r); pErr == nil {
+	b, err = io.ReadAll(r)
+	if err != nil {
+		return nil, err
+	}
+	if parts, pErr = parseBundleParts(b); pErr == nil {
 		return &resolvedBundleDataSource{
-			basePath: "", // use empty base path for archives
-			parts:    parts,
+			basePath:    "", // use empty base path for archives
+			parts:       parts,
+			bundleBytes: b,
 		}, nil
 	}
 
@@ -185,20 +200,19 @@ func isNotExistsError(err error) bool {
 // StreamBundleDataSource reads a (potentially multi-part) bundle from r and
 // returns a BundleDataSource for it.
 func StreamBundleDataSource(r io.Reader, basePath string) (BundleDataSource, error) {
-	parts, err := parseBundleParts(r)
+	b, err := io.ReadAll(r)
+	if err != nil {
+		return nil, err
+	}
+	parts, err := parseBundleParts(b)
 	if err != nil {
 		return nil, errors.NotValidf("cannot unmarshal bundle contents: %v", err)
 	}
 
-	return &resolvedBundleDataSource{parts: parts, basePath: basePath}, nil
+	return &resolvedBundleDataSource{parts: parts, bundleBytes: b, basePath: basePath}, nil
 }
 
-func parseBundleParts(r io.Reader) ([]*BundleDataPart, error) {
-	b, err := ioutil.ReadAll(r)
-	if err != nil {
-		return nil, err
-	}
-
+func parseBundleParts(b []byte) ([]*BundleDataPart, error) {
 	var (
 		// Ideally, we would be using a single reader and we would
 		// rewind it to read each block in structured and raw mode.
@@ -216,7 +230,7 @@ func parseBundleParts(r io.Reader) ([]*BundleDataPart, error) {
 	for docIdx := 0; ; docIdx++ {
 		var part BundleDataPart
 
-		err = structDec.Decode(&part.Data)
+		err := structDec.Decode(&part.Data)
 		if err == io.EOF {
 			break
 		} else if err != nil && !strings.HasPrefix(err.Error(), "yaml: unmarshal errors:") {
diff --git a/bundledatasrc_test.go b/bundledatasrc_test.go
index f72f8cb..5f887b8 100644
--- a/bundledatasrc_test.go
+++ b/bundledatasrc_test.go
@@ -6,7 +6,6 @@ package charm
 import (
 	"archive/zip"
 	"fmt"
-	"io/ioutil"
 	"os"
 	"path/filepath"
 	"strings"
@@ -22,29 +21,40 @@ type BundleDataSourceSuite struct {
 
 var _ = gc.Suite(&BundleDataSourceSuite{})
 
+var bundlePath = "internal/test-charm-repo/bundle/wordpress-multidoc/bundle.yaml"
+
 func (s *BundleDataSourceSuite) TestReadBundleFromLocalFile(c *gc.C) {
 	path := bundleDirPath(c, "wordpress-multidoc")
 	src, err := LocalBundleDataSource(filepath.Join(path, "bundle.yaml"))
 	c.Assert(err, gc.IsNil)
-	assertBundleSourceProcessed(c, src)
+
+	raw, err := os.ReadFile(bundlePath)
+	c.Assert(err, jc.ErrorIsNil)
+	assertBundleSourceProcessed(c, src, string(raw))
 }
 
 func (s *BundleDataSourceSuite) TestReadBundleFromExplodedArchiveFolder(c *gc.C) {
 	path := bundleDirPath(c, "wordpress-multidoc")
 	src, err := LocalBundleDataSource(path)
 	c.Assert(err, gc.IsNil)
-	assertBundleSourceProcessed(c, src)
+
+	raw, err := os.ReadFile(bundlePath)
+	c.Assert(err, jc.ErrorIsNil)
+	assertBundleSourceProcessed(c, src, string(raw))
 }
 
 func (s *BundleDataSourceSuite) TestReadBundleFromArchive(c *gc.C) {
 	path := archiveBundleDirPath(c, "wordpress-multidoc")
 	src, err := LocalBundleDataSource(path)
 	c.Assert(err, gc.IsNil)
-	assertBundleSourceProcessed(c, src)
+
+	raw, err := os.ReadFile(bundlePath)
+	c.Assert(err, jc.ErrorIsNil)
+	assertBundleSourceProcessed(c, src, string(raw))
 }
 
 func (s *BundleDataSourceSuite) TestReadBundleFromStream(c *gc.C) {
-	r := strings.NewReader(`
+	bundle := `
 applications:
   wordpress:
     charm: wordpress
@@ -68,18 +78,19 @@ applications:
         acl:
           admin: "admin"
           foo: "consume"
-`)
+`
 
-	src, err := StreamBundleDataSource(r, "https://example.com")
+	src, err := StreamBundleDataSource(strings.NewReader(bundle), "https://example.com")
 	c.Assert(err, gc.IsNil)
-	assertBundleSourceProcessed(c, src)
+	assertBundleSourceProcessed(c, src, bundle)
 }
 
-func assertBundleSourceProcessed(c *gc.C, src BundleDataSource) {
+func assertBundleSourceProcessed(c *gc.C, src BundleDataSource, bundle string) {
 	parts := src.Parts()
 	c.Assert(parts, gc.HasLen, 3)
 	assertFieldPresent(c, parts[1], "applications.wordpress.offers.offer1.endpoints")
 	assertFieldPresent(c, parts[2], "applications.wordpress.offers.offer1.acl.admin")
+	c.Assert(string(src.BundleBytes()), gc.Equals, bundle)
 }
 
 func assertFieldPresent(c *gc.C, part *BundleDataPart, path string) {
@@ -101,7 +112,7 @@ func assertFieldPresent(c *gc.C, part *BundleDataPart, path string) {
 }
 
 func (s *BundleDataSourceSuite) TestParseBundlePartsStrict(c *gc.C) {
-	r := strings.NewReader(`
+	b := []byte(`
 applications:
   wordpress:
     charm: wordpress
@@ -128,7 +139,7 @@ applications:
           foo: "consume"
 `)
 
-	parts, err := parseBundleParts(r)
+	parts, err := parseBundleParts(b)
 	c.Assert(err, gc.IsNil)
 	c.Assert(parts, gc.HasLen, 3)
 	c.Assert(parts[0].UnmarshallError, gc.NotNil)
@@ -148,7 +159,7 @@ func (s *BundleDataSourceSuite) TestResolveAbsoluteFileInclude(c *gc.C) {
 	c.Assert(err, gc.IsNil)
 
 	expContent := "example content\n"
-	c.Assert(ioutil.WriteFile(target, []byte(expContent), os.ModePerm), gc.IsNil)
+	c.Assert(os.WriteFile(target, []byte(expContent), os.ModePerm), gc.IsNil)
 
 	ds := new(resolvedBundleDataSource)
 
@@ -163,7 +174,7 @@ func (s *BundleDataSourceSuite) TestResolveRelativeFileInclude(c *gc.C) {
 	c.Assert(err, gc.IsNil)
 
 	expContent := "example content\n"
-	c.Assert(ioutil.WriteFile(target, []byte(expContent), os.ModePerm), gc.IsNil)
+	c.Assert(os.WriteFile(target, []byte(expContent), os.ModePerm), gc.IsNil)
 
 	ds := &resolvedBundleDataSource{
 		basePath: relTo,
@@ -226,7 +237,7 @@ func assertIsDir(c *gc.C, path string) {
 
 func archiveBundleDirPath(c *gc.C, name string) string {
 	src := filepath.Join("internal/test-charm-repo/bundle", name, "bundle.yaml")
-	srcYaml, err := ioutil.ReadFile(src)
+	srcYaml, err := os.ReadFile(src)
 	c.Assert(err, gc.IsNil)
 
 	dstPath := filepath.Join(c.MkDir(), "bundle.zip")
diff --git a/bundledir.go b/bundledir.go
index 10c5972..41d2f9b 100644
--- a/bundledir.go
+++ b/bundledir.go
@@ -6,16 +6,16 @@ package charm
 import (
 	"fmt"
 	"io"
-	"io/ioutil"
 	"os"
 	"path/filepath"
 )
 
 // BundleDir defines a bundle from a given directory.
 type BundleDir struct {
-	Path   string
-	data   *BundleData
-	readMe string
+	Path        string
+	data        *BundleData
+	bundleBytes []byte
+	readMe      string
 
 	containsOverlays bool
 }
@@ -27,16 +27,16 @@ var _ Bundle = (*BundleDir)(nil)
 // bundle directory. It does not verify the bundle data.
 func ReadBundleDir(path string) (dir *BundleDir, err error) {
 	dir = &BundleDir{Path: path}
-	file, err := os.Open(dir.join("bundle.yaml"))
+	b, err := os.ReadFile(dir.join("bundle.yaml"))
 	if err != nil {
 		return nil, err
 	}
-	dir.data, dir.containsOverlays, err = readBaseFromMultidocBundle(file)
-	file.Close()
+	dir.bundleBytes = b
+	dir.data, dir.containsOverlays, err = readBaseFromMultidocBundle(b)
 	if err != nil {
 		return nil, err
 	}
-	readMe, err := ioutil.ReadFile(dir.join("README.md"))
+	readMe, err := os.ReadFile(dir.join("README.md"))
 	if err != nil {
 		return nil, fmt.Errorf("cannot read README file: %v", err)
 	}
@@ -49,6 +49,11 @@ func (dir *BundleDir) Data() *BundleData {
 	return dir.data
 }
 
+// BundleBytes implements Bundle.BundleBytes
+func (dir *BundleDir) BundleBytes() []byte {
+	return dir.bundleBytes
+}
+
 // ReadMe returns the contents of the bundle's README.md file.
 func (dir *BundleDir) ReadMe() string {
 	return dir.readMe
diff --git a/bundledir_test.go b/bundledir_test.go
index 6bb4d70..882eca4 100644
--- a/bundledir_test.go
+++ b/bundledir_test.go
@@ -23,7 +23,7 @@ func (s *BundleDirSuite) TestReadBundleDir(c *gc.C) {
 	path := bundleDirPath(c, "wordpress-simple")
 	dir, err := charm.ReadBundleDir(path)
 	c.Assert(err, gc.IsNil)
-	checkWordpressBundle(c, dir, path)
+	checkWordpressBundle(c, dir, path, "wordpress-simple")
 }
 
 func (s *BundleDirSuite) TestReadBundleDirWithoutREADME(c *gc.C) {
diff --git a/overlay_test.go b/overlay_test.go
index fb607cf..67d079a 100644
--- a/overlay_test.go
+++ b/overlay_test.go
@@ -4,7 +4,6 @@
 package charm_test
 
 import (
-	"io/ioutil"
 	"os"
 	"path/filepath"
 	"sort"
@@ -954,6 +953,10 @@ func (s srcWithFakeIncludeResolver) Parts() []*charm.BundleDataPart {
 	return s.src.Parts()
 }
 
+func (s srcWithFakeIncludeResolver) BundleBytes() []byte {
+	return s.src.BundleBytes()
+}
+
 func (s srcWithFakeIncludeResolver) BasePath() string {
 	return s.src.BasePath()
 }
@@ -987,7 +990,7 @@ func testBundleMergeResult(c *gc.C, src, exp string) {
 }
 
 func mustWriteFile(c *gc.C, path, content string) {
-	err := ioutil.WriteFile(path, []byte(content), os.ModePerm)
+	err := os.WriteFile(path, []byte(content), os.ModePerm)
 	c.Assert(err, gc.IsNil)
 }