diff --git a/.gx/lastpubver b/.gx/lastpubver
deleted file mode 100644
index cf7cad5..0000000
--- a/.gx/lastpubver
+++ /dev/null
@@ -1 +0,0 @@
-2.0.7: QmRHcZ5ngUxZo8phLR3fpoqk9wA7VdGc5mhwkGSnB2nZ9F
diff --git a/.travis.yml b/.travis.yml
index 5163d69..936d6a4 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -4,7 +4,7 @@ os:
 language: go
 
 go:
-  - 1.11.x
+  - 1.14.x
 
 env:
   global:
diff --git a/serialfile.go b/serialfile.go
index fbb7a29..f56fcc6 100644
--- a/serialfile.go
+++ b/serialfile.go
@@ -3,15 +3,13 @@ package files
 import (
 	"errors"
 	"fmt"
-	"io"
 	"io/ioutil"
 	"os"
 	"path/filepath"
 )
 
 // serialFile implements Node, and reads from a path on the OS filesystem.
-// No more than one file will be opened at a time (directories will advance
-// to the next file when NextFile() is called).
+// No more than one file will be opened at a time.
 type serialFile struct {
 	path   string
 	files  []os.FileInfo
@@ -53,7 +51,7 @@ func NewSerialFileWithFilter(path string, filter *Filter, stat os.FileInfo) (Nod
 		return NewReaderPathFile(path, file, stat)
 	case mode.IsDir():
 		// for directories, stat all of the contents first, so we know what files to
-		// open when NextFile() is called
+		// open when Entries() is called
 		contents, err := ioutil.ReadDir(path)
 		if err != nil {
 			return nil, err
@@ -124,38 +122,6 @@ func (f *serialFile) Entries() DirIterator {
 	}
 }
 
-func (f *serialFile) NextFile() (string, Node, error) {
-	// if there aren't any files left in the root directory, we're done
-	if len(f.files) == 0 {
-		return "", nil, io.EOF
-	}
-
-	stat := f.files[0]
-	f.files = f.files[1:]
-
-	for !f.filter.ShouldExclude(stat) {
-		if len(f.files) == 0 {
-			return "", nil, io.EOF
-		}
-
-		stat = f.files[0]
-		f.files = f.files[1:]
-	}
-
-	// open the next file
-	filePath := filepath.ToSlash(filepath.Join(f.path, stat.Name()))
-
-	// recursively call the constructor on the next file
-	// if it's a regular file, we will open it as a ReaderFile
-	// if it's a directory, files in it will be opened serially
-	sf, err := NewSerialFileWithFilter(filePath, f.filter, stat)
-	if err != nil {
-		return "", nil, err
-	}
-
-	return stat.Name(), sf, nil
-}
-
 func (f *serialFile) Close() error {
 	return nil
 }