diff --git a/internal/chunk/control/control.go b/internal/chunk/control/control.go
index ab4ff2a1..69d19354 100644
--- a/internal/chunk/control/control.go
+++ b/internal/chunk/control/control.go
@@ -107,7 +107,7 @@ type Error struct {
 }
 
 func (e Error) Error() string {
-	return fmt.Sprintf("controller error in %s on %s: %v", e.Subroutine, e.Stage, e.Err)
+	return fmt.Sprintf("controller error in subroutine %s on stage %s: %v", e.Subroutine, e.Stage, e.Err)
 }
 
 func (c *Controller) Run(ctx context.Context, list *structures.EntityList) error {
diff --git a/internal/chunk/directory.go b/internal/chunk/directory.go
index 1dc6c309..f2282eea 100644
--- a/internal/chunk/directory.go
+++ b/internal/chunk/directory.go
@@ -16,7 +16,7 @@ import (
 	"github.com/slack-go/slack"
 )
 
-const ext = ".json.gz"
+const chunkExt = ".json.gz"
 
 // common filenames
 const (
@@ -119,7 +119,7 @@ func (d *Directory) Channels() ([]slack.Channel, error) {
 		if err != nil {
 			return err
 		}
-		if !strings.HasSuffix(path, ext) {
+		if !strings.HasSuffix(path, chunkExt) {
 			return nil
 		} else if de.IsDir() {
 			return nil
@@ -145,6 +145,7 @@ func (d *Directory) Name() string {
 	return d.dir
 }
 
+// loadChanInfo loads the channel info from the file with full path.
 func (d *Directory) loadChanInfo(fullpath string) ([]slack.Channel, error) {
 	f, err := d.openRAW(fullpath)
 	if err != nil {
@@ -255,7 +256,7 @@ func openfile(filename string) (*os.File, error) {
 
 // filename returns the full path of the chunk file with the given fileID.
 func (d *Directory) filename(id FileID) string {
-	return filepath.Join(d.dir, string(id)+ext)
+	return filepath.Join(d.dir, string(id)+chunkExt)
 }
 
 // Create creates the chunk file with the given name.  Extension is appended
diff --git a/internal/chunk/file.go b/internal/chunk/file.go
index 9339f089..b1a1290b 100644
--- a/internal/chunk/file.go
+++ b/internal/chunk/file.go
@@ -136,6 +136,9 @@ func caller(steps int) string {
 	return name
 }
 
+// ensure ensures that the file index was generated.
+//
+// TODO: maybe it shouldn't panic.
 func (f *File) ensure() {
 	if f.idx == nil {
 		log.Panicf("internal error:  %s called before File.Open", caller(1))
@@ -267,9 +270,20 @@ func (p *File) AllChannels() ([]slack.Channel, error) {
 // info API.
 func (f *File) AllChannelInfos() ([]slack.Channel, error) {
 	f.ensure()
-	return allForOffsets(f, f.idx.offsetsWithPrefix(chanInfoPrefix), func(c *Chunk) []slack.Channel {
+	chans, err := allForOffsets(f, f.idx.offsetsWithPrefix(chanInfoPrefix), func(c *Chunk) []slack.Channel {
 		return []slack.Channel{*c.Channel}
 	})
+	if err != nil {
+		return nil, err
+	}
+	for i := range chans {
+		members, err := f.ChannelUsers(chans[i].ID)
+		if err != nil {
+			return nil, err
+		}
+		chans[i].Members = members
+	}
+	return chans, nil
 }
 
 // AllChannelInfoWithMembers returns all channels with Members populated.
diff --git a/internal/chunk/file_test.go b/internal/chunk/file_test.go
index 679a5529..7b4cb4c7 100644
--- a/internal/chunk/file_test.go
+++ b/internal/chunk/file_test.go
@@ -713,6 +713,12 @@ func mkindex(rs io.ReadSeeker) index {
 }
 
 func TestFile_AllChannelInfos(t *testing.T) {
+	c0wus := *testChunks[0].Channel
+	c0wus.Members = testChunks[1].ChannelUsers
+
+	c6wus := *testChunks[6].Channel
+	c6wus.Members = testChunks[7].ChannelUsers
+
 	type fields struct {
 		rs io.ReadSeeker
 	}
@@ -728,8 +734,8 @@ func TestFile_AllChannelInfos(t *testing.T) {
 				rs: marshalChunks(testChunks...),
 			},
 			[]slack.Channel{
-				*testChunks[0].Channel,
-				*testChunks[6].Channel,
+				c0wus,
+				c6wus,
 			},
 			false,
 		},
@@ -745,9 +751,7 @@ func TestFile_AllChannelInfos(t *testing.T) {
 				t.Errorf("File.AllChannelInfos() error = %v, wantErr %v", err, tt.wantErr)
 				return
 			}
-			if !reflect.DeepEqual(got, tt.want) {
-				t.Errorf("File.AllChannelInfos() = %v, want %v", got, tt.want)
-			}
+			assert.Equal(t, tt.want, got)
 		})
 	}
 }