diff --git a/internal/fusefrontend_reverse/ctlsock_interface.go b/internal/fusefrontend_reverse/ctlsock_interface.go
index 448663f..376814d 100644
--- a/internal/fusefrontend_reverse/ctlsock_interface.go
+++ b/internal/fusefrontend_reverse/ctlsock_interface.go
@@ -6,14 +6,14 @@ import (
 	"github.com/rfjakob/gocryptfs/internal/ctlsock"
 )
 
-var _ ctlsock.Interface = &reverseFS{} // Verify that interface is implemented.
+var _ ctlsock.Interface = &ReverseFS{} // Verify that interface is implemented.
 
 // EncryptPath implements ctlsock.Backend
-func (rfs *reverseFS) EncryptPath(plainPath string) (string, error) {
+func (rfs *ReverseFS) EncryptPath(plainPath string) (string, error) {
 	return "", errors.New("Not implemented")
 }
 
 // DecryptPath implements ctlsock.Backend
-func (rfs *reverseFS) DecryptPath(plainPath string) (string, error) {
+func (rfs *ReverseFS) DecryptPath(plainPath string) (string, error) {
 	return rfs.decryptPath(plainPath)
 }
diff --git a/internal/fusefrontend_reverse/reverse_longnames.go b/internal/fusefrontend_reverse/reverse_longnames.go
index d59664d..96fa613 100644
--- a/internal/fusefrontend_reverse/reverse_longnames.go
+++ b/internal/fusefrontend_reverse/reverse_longnames.go
@@ -39,7 +39,7 @@ func initLongnameCache() {
 }
 
 // findLongnameParent converts "gocryptfs.longname.XYZ" to the plaintext name
-func (rfs *reverseFS) findLongnameParent(dir string, dirIV []byte, longname string) (plaintextName string, err error) {
+func (rfs *ReverseFS) findLongnameParent(dir string, dirIV []byte, longname string) (plaintextName string, err error) {
 	longnameCacheLock.Lock()
 	hit := longnameParentCache[longname]
 	longnameCacheLock.Unlock()
@@ -78,7 +78,7 @@ func (rfs *reverseFS) findLongnameParent(dir string, dirIV []byte, longname stri
 	return hit, nil
 }
 
-func (rfs *reverseFS) newNameFile(relPath string) (nodefs.File, fuse.Status) {
+func (rfs *ReverseFS) newNameFile(relPath string) (nodefs.File, fuse.Status) {
 	dotName := filepath.Base(relPath)                                    // gocryptfs.longname.XYZ.name
 	longname := dotName[:len(dotName)-len(nametransform.LongNameSuffix)] // gocryptfs.longname.XYZ
 
@@ -94,5 +94,5 @@ func (rfs *reverseFS) newNameFile(relPath string) (nodefs.File, fuse.Status) {
 	}
 	content := []byte(rfs.nameTransform.EncryptName(e, dirIV))
 	parentFile := filepath.Join(rfs.args.Cipherdir, pDir)
-	return rfs.NewVirtualFile(content, parentFile)
+	return rfs.newVirtualFile(content, parentFile)
 }
diff --git a/internal/fusefrontend_reverse/rfile.go b/internal/fusefrontend_reverse/rfile.go
index 5606e70..c5ca991 100644
--- a/internal/fusefrontend_reverse/rfile.go
+++ b/internal/fusefrontend_reverse/rfile.go
@@ -27,7 +27,7 @@ type reverseFile struct {
 	contentEnc *contentenc.ContentEnc
 }
 
-func (rfs *reverseFS) NewFile(relPath string, flags uint32) (nodefs.File, fuse.Status) {
+func (rfs *ReverseFS) newFile(relPath string, flags uint32) (nodefs.File, fuse.Status) {
 	absPath, err := rfs.abs(rfs.decryptPath(relPath))
 	if err != nil {
 		return nil, fuse.ToStatus(err)
diff --git a/internal/fusefrontend_reverse/rfs.go b/internal/fusefrontend_reverse/rfs.go
index 84348f7..7f102cf 100644
--- a/internal/fusefrontend_reverse/rfs.go
+++ b/internal/fusefrontend_reverse/rfs.go
@@ -25,7 +25,9 @@ const (
 	DirIVMode = syscall.S_IFREG | 0400
 )
 
-type reverseFS struct {
+// ReverseFS implements the pathfs.FileSystem interface and provides an
+// encrypted view of a plaintext directory.
+type ReverseFS struct {
 	// Embed pathfs.defaultFileSystem for a ENOSYS implementation of all methods
 	pathfs.FileSystem
 	// pathfs.loopbackFileSystem, see go-fuse/fuse/pathfs/loopback.go
@@ -44,12 +46,12 @@ type reverseFS struct {
 	inoMapLock sync.Mutex
 }
 
-var _ pathfs.FileSystem = &reverseFS{}
+var _ pathfs.FileSystem = &ReverseFS{}
 
 // NewFS returns an encrypted FUSE overlay filesystem.
 // In this case (reverse mode) the backing directory is plain-text and
-// reverseFS provides an encrypted view.
-func NewFS(args fusefrontend.Args) *reverseFS {
+// ReverseFS provides an encrypted view.
+func NewFS(args fusefrontend.Args) *ReverseFS {
 	if args.CryptoBackend != cryptocore.BackendAESSIV {
 		panic("reverse mode must use AES-SIV, everything else is insecure")
 	}
@@ -58,7 +60,7 @@ func NewFS(args fusefrontend.Args) *reverseFS {
 	contentEnc := contentenc.New(cryptoCore, contentenc.DefaultBS)
 	nameTransform := nametransform.New(cryptoCore, args.LongNames, args.Raw64)
 
-	return &reverseFS{
+	return &ReverseFS{
 		// pathfs.defaultFileSystem returns ENOSYS for all operations
 		FileSystem:    pathfs.NewDefaultFileSystem(),
 		loopbackfs:    pathfs.NewLoopbackFileSystem(args.Cipherdir),
@@ -82,7 +84,7 @@ func relDir(path string) string {
 }
 
 // dirIVAttr handles GetAttr requests for the virtual gocryptfs.diriv files.
-func (rfs *reverseFS) dirIVAttr(relPath string, context *fuse.Context) (*fuse.Attr, fuse.Status) {
+func (rfs *ReverseFS) dirIVAttr(relPath string, context *fuse.Context) (*fuse.Attr, fuse.Status) {
 	cDir := relDir(relPath)
 	dir, err := rfs.decryptPath(cDir)
 	if err != nil {
@@ -115,7 +117,7 @@ func (rfs *reverseFS) dirIVAttr(relPath string, context *fuse.Context) (*fuse.At
 }
 
 // isDirIV determines if the path points to a gocryptfs.diriv file
-func (rfs *reverseFS) isDirIV(relPath string) bool {
+func (rfs *ReverseFS) isDirIV(relPath string) bool {
 	if rfs.args.PlaintextNames {
 		return false
 	}
@@ -124,7 +126,7 @@ func (rfs *reverseFS) isDirIV(relPath string) bool {
 
 // isNameFile determines if the path points to a gocryptfs.longname.*.name
 // file
-func (rfs *reverseFS) isNameFile(relPath string) bool {
+func (rfs *ReverseFS) isNameFile(relPath string) bool {
 	if rfs.args.PlaintextNames {
 		return false
 	}
@@ -136,7 +138,7 @@ func (rfs *reverseFS) isNameFile(relPath string) bool {
 // and the ciphertext path is "gocryptfs.conf".
 // "gocryptfs.conf" then maps to ".gocryptfs.reverse.conf" in the plaintext
 // directory.
-func (rfs *reverseFS) isTranslatedConfig(relPath string) bool {
+func (rfs *ReverseFS) isTranslatedConfig(relPath string) bool {
 	if rfs.args.ConfigCustom {
 		return false
 	}
@@ -146,7 +148,7 @@ func (rfs *reverseFS) isTranslatedConfig(relPath string) bool {
 	return false
 }
 
-func (rfs *reverseFS) inoAwareStat(relPlainPath string) (*fuse.Attr, fuse.Status) {
+func (rfs *ReverseFS) inoAwareStat(relPlainPath string) (*fuse.Attr, fuse.Status) {
 	absPath, err := rfs.abs(relPlainPath, nil)
 	if err != nil {
 		return nil, fuse.ToStatus(err)
@@ -182,7 +184,7 @@ func (rfs *reverseFS) inoAwareStat(relPlainPath string) (*fuse.Attr, fuse.Status
 }
 
 // GetAttr - FUSE call
-func (rfs *reverseFS) GetAttr(relPath string, context *fuse.Context) (*fuse.Attr, fuse.Status) {
+func (rfs *ReverseFS) GetAttr(relPath string, context *fuse.Context) (*fuse.Attr, fuse.Status) {
 	if rfs.isTranslatedConfig(relPath) {
 		return rfs.inoAwareStat(configfile.ConfReverseName)
 	}
@@ -224,7 +226,7 @@ func (rfs *reverseFS) GetAttr(relPath string, context *fuse.Context) (*fuse.Attr
 }
 
 // Access - FUSE call
-func (rfs *reverseFS) Access(relPath string, mode uint32, context *fuse.Context) fuse.Status {
+func (rfs *ReverseFS) Access(relPath string, mode uint32, context *fuse.Context) fuse.Status {
 	if rfs.isTranslatedConfig(relPath) {
 		return fuse.OK
 	}
@@ -239,7 +241,7 @@ func (rfs *reverseFS) Access(relPath string, mode uint32, context *fuse.Context)
 }
 
 // Open - FUSE call
-func (rfs *reverseFS) Open(relPath string, flags uint32, context *fuse.Context) (fuseFile nodefs.File, status fuse.Status) {
+func (rfs *ReverseFS) Open(relPath string, flags uint32, context *fuse.Context) (fuseFile nodefs.File, status fuse.Status) {
 	if rfs.isTranslatedConfig(relPath) {
 		return rfs.loopbackfs.Open(configfile.ConfReverseName, flags, context)
 	}
@@ -249,10 +251,10 @@ func (rfs *reverseFS) Open(relPath string, flags uint32, context *fuse.Context)
 	if rfs.isNameFile(relPath) {
 		return rfs.newNameFile(relPath)
 	}
-	return rfs.NewFile(relPath, flags)
+	return rfs.newFile(relPath, flags)
 }
 
-func (rfs *reverseFS) openDirPlaintextnames(relPath string, entries []fuse.DirEntry) ([]fuse.DirEntry, fuse.Status) {
+func (rfs *ReverseFS) openDirPlaintextnames(relPath string, entries []fuse.DirEntry) ([]fuse.DirEntry, fuse.Status) {
 	if relPath != "" || rfs.args.ConfigCustom {
 		return entries, fuse.OK
 	}
@@ -278,7 +280,7 @@ func (rfs *reverseFS) openDirPlaintextnames(relPath string, entries []fuse.DirEn
 }
 
 // OpenDir - FUSE readdir call
-func (rfs *reverseFS) OpenDir(cipherPath string, context *fuse.Context) ([]fuse.DirEntry, fuse.Status) {
+func (rfs *ReverseFS) OpenDir(cipherPath string, context *fuse.Context) ([]fuse.DirEntry, fuse.Status) {
 	relPath, err := rfs.decryptPath(cipherPath)
 	if err != nil {
 		return nil, fuse.ToStatus(err)
@@ -329,12 +331,12 @@ func (rfs *reverseFS) OpenDir(cipherPath string, context *fuse.Context) ([]fuse.
 }
 
 // StatFs - FUSE call
-func (rfs *reverseFS) StatFs(name string) *fuse.StatfsOut {
+func (rfs *ReverseFS) StatFs(name string) *fuse.StatfsOut {
 	return rfs.loopbackfs.StatFs(name)
 }
 
 // Readlink - FUSE call
-func (rfs *reverseFS) Readlink(cipherPath string, context *fuse.Context) (string, fuse.Status) {
+func (rfs *ReverseFS) Readlink(cipherPath string, context *fuse.Context) (string, fuse.Status) {
 	absPath, err := rfs.abs(rfs.decryptPath(cipherPath))
 	if err != nil {
 		return "", fuse.ToStatus(err)
diff --git a/internal/fusefrontend_reverse/rpath.go b/internal/fusefrontend_reverse/rpath.go
index c8df8fe..2740104 100644
--- a/internal/fusefrontend_reverse/rpath.go
+++ b/internal/fusefrontend_reverse/rpath.go
@@ -36,14 +36,14 @@ func derivePathIV(path string, purpose ivPurposeType) []byte {
 	return hash[:nametransform.DirIVLen]
 }
 
-func (rfs *reverseFS) abs(relPath string, err error) (string, error) {
+func (rfs *ReverseFS) abs(relPath string, err error) (string, error) {
 	if err != nil {
 		return "", err
 	}
 	return filepath.Join(rfs.args.Cipherdir, relPath), nil
 }
 
-func (rfs *reverseFS) decryptPath(relPath string) (string, error) {
+func (rfs *ReverseFS) decryptPath(relPath string) (string, error) {
 	if rfs.args.PlaintextNames || relPath == "" {
 		return relPath, nil
 	}
diff --git a/internal/fusefrontend_reverse/virtualfile.go b/internal/fusefrontend_reverse/virtualfile.go
index 2447e16..cca4349 100644
--- a/internal/fusefrontend_reverse/virtualfile.go
+++ b/internal/fusefrontend_reverse/virtualfile.go
@@ -8,13 +8,13 @@ import (
 	"github.com/hanwen/go-fuse/fuse/nodefs"
 )
 
-func (rfs *reverseFS) newDirIVFile(cRelPath string) (nodefs.File, fuse.Status) {
+func (rfs *ReverseFS) newDirIVFile(cRelPath string) (nodefs.File, fuse.Status) {
 	cDir := saneDir(cRelPath)
 	absDir, err := rfs.abs(rfs.decryptPath(cDir))
 	if err != nil {
 		return nil, fuse.ToStatus(err)
 	}
-	return rfs.NewVirtualFile(derivePathIV(cDir, ivPurposeDirIV), absDir)
+	return rfs.newVirtualFile(derivePathIV(cDir, ivPurposeDirIV), absDir)
 }
 
 type virtualFile struct {
@@ -28,7 +28,7 @@ type virtualFile struct {
 	ino uint64
 }
 
-func (rfs *reverseFS) NewVirtualFile(content []byte, parentFile string) (nodefs.File, fuse.Status) {
+func (rfs *ReverseFS) newVirtualFile(content []byte, parentFile string) (nodefs.File, fuse.Status) {
 	return &virtualFile{
 		File:       nodefs.NewDefaultFile(),
 		content:    content,
diff --git a/internal/nametransform/raw64_go1.5.go b/internal/nametransform/raw64_go1.5.go
index aa7f7fd..1896be3 100644
--- a/internal/nametransform/raw64_go1.5.go
+++ b/internal/nametransform/raw64_go1.5.go
@@ -7,6 +7,7 @@ import (
 )
 
 const (
+	// HaveRaw64 is true when Go is new enough to have base64.RawURLEncoding
 	HaveRaw64 = true
 )