diff --git a/README.md b/README.md
index ef89244..2626327 100644
--- a/README.md
+++ b/README.md
@@ -22,6 +22,11 @@
 - `reformat` reformat lineage (supporting STDIN)
 - `name2taxid` query taxid by taxon scientific name (supporting STDIN)
 
+Misc
+
+- `version`   print version information and check for update
+- `genautocomplete` generate shell autocompletion script
+
 ## Installation
 
 Go to [Download Page](http://bioinf.shenwei.me/taxonkit/download) for more download options and changelogs.
@@ -58,6 +63,25 @@ And then:
 
     go get -u github.com/shenwei356/taxonkit/taxonkit
 
+## Bash-completion
+
+Note: The current version supports Bash only.
+This should work for *nix systems with Bash installed.
+
+Howto:
+
+1. run: `taxonkit genautocomplete`
+
+2. create and edit `~/.bash_completion` file if you don't have it.
+
+        nano ~/.bash_completion
+
+    add the following:
+
+        for bcfile in ~/.bash_completion.d/* ; do
+          . $bcfile
+        done
+
 ## Contact
 
 Email me for any problem when using taxonkit. shenwei356(at)gmail.com
diff --git a/doc/docs/download.md b/doc/docs/download.md
index 19c9525..bde6933 100644
--- a/doc/docs/download.md
+++ b/doc/docs/download.md
@@ -6,23 +6,25 @@
 
 ## Current Version
 
-[TaxonKit v0.2.0](https://github.com/shenwei356/taxonkit/releases/tag/v0.2.0)
-[![Github Releases (by Release)](https://img.shields.io/github/downloads/shenwei356/taxonkit/v0.2.0/total.svg)](https://github.com/shenwei356/taxonkit/releases/tag/v0.2.0)
+[TaxonKit v0.2.1](https://github.com/shenwei356/taxonkit/releases/tag/v0.2.1)
+[![Github Releases (by Release)](https://img.shields.io/github/downloads/shenwei356/taxonkit/v0.2.1/total.svg)](https://github.com/shenwei356/taxonkit/releases/tag/v0.2.1)
 
-- add command `name2taxid` to query taxid by taxon scientific name.
-- `lineage`, `reformat`: ***changed flags and default operations***,
- check the [usage](http://bioinf.shenwei.me/taxonkit/usage/).
+- `taxonkit list`: fix bug of no output for leaf nodes of the taxonomic tree.
+[#4](https://github.com/shenwei356/taxonkit/issues/4)
+- add new command `genautocomplete` to generate **shell autocompletion** script!
 
 Links:
 
+***Tip: run `taxonkit version` to check update !!!***
+
 OS     |Arch      |File, (mirror为中国用户下载镜像链接)                                                                                                                                                                                             |Download Count
 :------|:---------|:----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|:-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
-Linux  |32-bit    |[taxonkit_linux_386.tar.gz](https://github.com/shenwei356/taxonkit/releases/download/v0.2.0/taxonkit_linux_386.tar.gz), ([mirror](http://app.shenwei.me/data/taxonkit/taxonkit_linux_386.tar.gz))                            |[![Github Releases (by Asset)](https://img.shields.io/github/downloads/shenwei356/taxonkit/latest/taxonkit_linux_386.tar.gz.svg?maxAge=3600)](https://github.com/shenwei356/taxonkit/releases/download/v0.2.0/taxonkit_linux_386.tar.gz)
-Linux  |**64-bit**|[**taxonkit_linux_amd64.tar.gz**](https://github.com/shenwei356/taxonkit/releases/download/v0.2.0/taxonkit_linux_amd64.tar.gz), ([mirror](http://app.shenwei.me/data/taxonkit/taxonkit_linux_amd64.tar.gz))                  |[![Github Releases (by Asset)](https://img.shields.io/github/downloads/shenwei356/taxonkit/latest/taxonkit_linux_amd64.tar.gz.svg?maxAge=3600)](https://github.com/shenwei356/taxonkit/releases/download/v0.2.0/taxonkit_linux_amd64.tar.gz)
-OS X   |32-bit    |[taxonkit_darwin_386.tar.gz](https://github.com/shenwei356/taxonkit/releases/download/v0.2.0/taxonkit_darwin_386.tar.gz), ([mirror](http://app.shenwei.me/data/taxonkit/taxonkit_darwin_386.tar.gz))                         |[![Github Releases (by Asset)](https://img.shields.io/github/downloads/shenwei356/taxonkit/latest/taxonkit_darwin_386.tar.gz.svg?maxAge=3600)](https://github.com/shenwei356/taxonkit/releases/download/v0.2.0/taxonkit_darwin_386.tar.gz)
-OS X   |**64-bit**|[**taxonkit_darwin_amd64.tar.gz**](https://github.com/shenwei356/taxonkit/releases/download/v0.2.0/taxonkit_darwin_amd64.tar.gz), ([mirror](http://app.shenwei.me/data/taxonkit/taxonkit_darwin_amd64.tar.gz))               |[![Github Releases (by Asset)](https://img.shields.io/github/downloads/shenwei356/taxonkit/latest/taxonkit_darwin_amd64.tar.gz.svg?maxAge=3600)](https://github.com/shenwei356/taxonkit/releases/download/v0.2.0/taxonkit_darwin_amd64.tar.gz)
-Windows|32-bit    |[taxonkit_windows_386.exe.tar.gz](https://github.com/shenwei356/taxonkit/releases/download/v0.2.0/taxonkit_windows_386.exe.tar.gz), ([mirror](http://app.shenwei.me/data/taxonkit/taxonkit_windows_386.exe.tar.gz))          |[![Github Releases (by Asset)](https://img.shields.io/github/downloads/shenwei356/taxonkit/latest/taxonkit_windows_386.exe.tar.gz.svg?maxAge=3600)](https://github.com/shenwei356/taxonkit/releases/download/v0.2.0/taxonkit_windows_386.exe.tar.gz)
-Windows|**64-bit**|[**taxonkit_windows_amd64.exe.tar.gz**](https://github.com/shenwei356/taxonkit/releases/download/v0.2.0/taxonkit_windows_amd64.exe.tar.gz), ([mirror](http://app.shenwei.me/data/taxonkit/taxonkit_windows_amd64.exe.tar.gz))|[![Github Releases (by Asset)](https://img.shields.io/github/downloads/shenwei356/taxonkit/latest/taxonkit_windows_amd64.exe.tar.gz.svg?maxAge=3600)](https://github.com/shenwei356/taxonkit/releases/download/v0.2.0/taxonkit_windows_amd64.exe.tar.gz)
+Linux  |32-bit    |[taxonkit_linux_386.tar.gz](https://github.com/shenwei356/taxonkit/releases/download/v0.2.1/taxonkit_linux_386.tar.gz), ([mirror](http://app.shenwei.me/data/taxonkit/taxonkit_linux_386.tar.gz))                            |[![Github Releases (by Asset)](https://img.shields.io/github/downloads/shenwei356/taxonkit/latest/taxonkit_linux_386.tar.gz.svg?maxAge=3600)](https://github.com/shenwei356/taxonkit/releases/download/v0.2.1/taxonkit_linux_386.tar.gz)
+Linux  |**64-bit**|[**taxonkit_linux_amd64.tar.gz**](https://github.com/shenwei356/taxonkit/releases/download/v0.2.1/taxonkit_linux_amd64.tar.gz), ([mirror](http://app.shenwei.me/data/taxonkit/taxonkit_linux_amd64.tar.gz))                  |[![Github Releases (by Asset)](https://img.shields.io/github/downloads/shenwei356/taxonkit/latest/taxonkit_linux_amd64.tar.gz.svg?maxAge=3600)](https://github.com/shenwei356/taxonkit/releases/download/v0.2.1/taxonkit_linux_amd64.tar.gz)
+OS X   |32-bit    |[taxonkit_darwin_386.tar.gz](https://github.com/shenwei356/taxonkit/releases/download/v0.2.1/taxonkit_darwin_386.tar.gz), ([mirror](http://app.shenwei.me/data/taxonkit/taxonkit_darwin_386.tar.gz))                         |[![Github Releases (by Asset)](https://img.shields.io/github/downloads/shenwei356/taxonkit/latest/taxonkit_darwin_386.tar.gz.svg?maxAge=3600)](https://github.com/shenwei356/taxonkit/releases/download/v0.2.1/taxonkit_darwin_386.tar.gz)
+OS X   |**64-bit**|[**taxonkit_darwin_amd64.tar.gz**](https://github.com/shenwei356/taxonkit/releases/download/v0.2.1/taxonkit_darwin_amd64.tar.gz), ([mirror](http://app.shenwei.me/data/taxonkit/taxonkit_darwin_amd64.tar.gz))               |[![Github Releases (by Asset)](https://img.shields.io/github/downloads/shenwei356/taxonkit/latest/taxonkit_darwin_amd64.tar.gz.svg?maxAge=3600)](https://github.com/shenwei356/taxonkit/releases/download/v0.2.1/taxonkit_darwin_amd64.tar.gz)
+Windows|32-bit    |[taxonkit_windows_386.exe.tar.gz](https://github.com/shenwei356/taxonkit/releases/download/v0.2.1/taxonkit_windows_386.exe.tar.gz), ([mirror](http://app.shenwei.me/data/taxonkit/taxonkit_windows_386.exe.tar.gz))          |[![Github Releases (by Asset)](https://img.shields.io/github/downloads/shenwei356/taxonkit/latest/taxonkit_windows_386.exe.tar.gz.svg?maxAge=3600)](https://github.com/shenwei356/taxonkit/releases/download/v0.2.1/taxonkit_windows_386.exe.tar.gz)
+Windows|**64-bit**|[**taxonkit_windows_amd64.exe.tar.gz**](https://github.com/shenwei356/taxonkit/releases/download/v0.2.1/taxonkit_windows_amd64.exe.tar.gz), ([mirror](http://app.shenwei.me/data/taxonkit/taxonkit_windows_amd64.exe.tar.gz))|[![Github Releases (by Asset)](https://img.shields.io/github/downloads/shenwei356/taxonkit/latest/taxonkit_windows_amd64.exe.tar.gz.svg?maxAge=3600)](https://github.com/shenwei356/taxonkit/releases/download/v0.2.1/taxonkit_windows_amd64.exe.tar.gz)
 
 
 ## Installation
@@ -61,9 +63,32 @@ And then:
 
     go get -u github.com/shenwei356/taxonkit/taxonkit
 
+## Bash-completion
+
+Note: The current version supports Bash only.
+This should work for *nix systems with Bash installed.
+
+Howto:
+
+1. run: `taxonkit genautocomplete`
+
+2. create and edit `~/.bash_completion` file if you don't have it.
+
+        nano ~/.bash_completion
+
+    add the following:
+
+        for bcfile in ~/.bash_completion.d/* ; do
+          . $bcfile
+        done
 
 ## Previous Versions
 
+- [TaxonKit v0.2.0](https://github.com/shenwei356/taxonkit/releases/tag/v0.2.0)
+[![Github Releases (by Release)](https://img.shields.io/github/downloads/shenwei356/taxonkit/v0.2.0/total.svg)](https://github.com/shenwei356/taxonkit/releases/tag/v0.2.0)
+    - add command `name2taxid` to query taxid by taxon scientific name.
+    - `lineage`, `reformat`: ***changed flags and default operations***,
+ check the [usage](http://bioinf.shenwei.me/taxonkit/usage/).
 - [TaxonKit v0.1.8](https://github.com/shenwei356/taxonkit/releases/tag/v0.1.8)
 [![Github Releases (by Release)](https://img.shields.io/github/downloads/shenwei356/taxonkit/v0.1.8/total.svg)](https://github.com/shenwei356/taxonkit/releases/tag/v0.1.8)
     - `taxonkit lineage`, add an extra column of lineage in Taxid.
diff --git a/doc/docs/usage.md b/doc/docs/usage.md
index d59a4e7..8a7e5bb 100644
--- a/doc/docs/usage.md
+++ b/doc/docs/usage.md
@@ -15,7 +15,7 @@ Usage
 ```
 TaxonKit - Cross-platform and Efficient NCBI Taxonomy Toolkit
 
-Version: 0.2.0
+Version: 0.2.1
 
 Author: Wei Shen <shenwei356@gmail.com>
 
@@ -34,14 +34,16 @@ Usage:
   taxonkit [command]
 
 Available Commands:
-  help        Help about any command
-  lineage     query lineage of given taxids
-  list        list taxon tree of given taxids
-  name2taxid  query taxid by taxon scientific name
-  reformat    reformat lineage
-  version     print version information and check for update
+  genautocomplete generate shell autocompletion script
+  help            Help about any command
+  lineage         query lineage of given taxids
+  list            list taxon tree of given taxids
+  name2taxid      query taxid by taxon scientific name
+  reformat        reformat lineage
+  version         print version information and check for update
 
 Flags:
+  -h, --help                help for taxonkit
       --names-file string   names.dmp file (default "/home/shenwei/.taxonkit/names.dmp")
       --nodes-file string   nodes.dmp file (default "/home/shenwei/.taxonkit/nodes.dmp")
   -o, --out-file string     out file ("-" for stdout, suffix .gz for gzipped out) (default "-")
@@ -407,6 +409,39 @@ Example data
         Homo sapiens    9606    cellular organisms;Eukaryota;Opisthokonta;Metazoa;Eumetazoa;Bilateria;Deuterostomia;Chordata;Craniata;Vertebrata;Gnathostomata;Teleostomi;Euteleostomi;Sarcopterygii;Dipnotetrapodomorpha;Tetrapoda;Amniota;Mammalia;Theria;Eutheria;Boreoeutheria;Euarchontoglires;Primates;Haplorrhini;Simiiformes;Catarrhini;Hominoidea;Hominidae;Homininae;Homo;Homo sapiens        131567;2759;33154;33208;6072;33213;33511;7711;89593;7742;7776;117570;117571;8287;1338369;32523;32524;40674;32525;9347;1437010;314146;9443;376913;314293;9526;314295;9604;207598;9605;9606
         ...
 
+## genautocomplete
+
+Usage
+
+```
+generate shell autocompletion script
+
+Note: The current version supports Bash only.
+This should work for *nix systems with Bash installed.
+
+Howto:
+
+1. run: taxonkit genautocomplete
+
+2. create and edit ~/.bash_completion file if you don't have it.
+
+        nano ~/.bash_completion
+
+   add the following:
+
+        for bcfile in ~/.bash_completion.d/* ; do
+          . $bcfile
+        done
+
+Usage:
+  taxonkit genautocomplete [flags]
+
+Flags:
+      --file string   autocompletion file (default "/home/shenwei/.bash_completion.d/taxonkit.sh")
+  -h, --help          help for genautocomplete
+      --type string   autocompletion type (currently only bash supported) (default "bash")
+
+```
 
 <div id="disqus_thread"></div>
 <script>
diff --git a/taxonkit/cmd/genautocomplete.go b/taxonkit/cmd/genautocomplete.go
new file mode 100644
index 0000000..577257e
--- /dev/null
+++ b/taxonkit/cmd/genautocomplete.go
@@ -0,0 +1,83 @@
+// Copyright © 2016 Wei Shen <shenwei356@gmail.com>
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+
+package cmd
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+
+	homedir "github.com/mitchellh/go-homedir"
+	"github.com/shenwei356/util/pathutil"
+	"github.com/spf13/cobra"
+)
+
+// genautocompleteCmd represents the fq2fa command
+var genautocompleteCmd = &cobra.Command{
+	Use:   "genautocomplete",
+	Short: "generate shell autocompletion script",
+	Long: `generate shell autocompletion script
+
+Note: The current version supports Bash only.
+This should work for *nix systems with Bash installed.
+
+Howto:
+
+1. run: taxonkit genautocomplete
+
+2. create and edit ~/.bash_completion file if you don't have it.
+
+        nano ~/.bash_completion
+
+    add the following:
+
+        for bcfile in ~/.bash_completion.d/* ; do
+          . $bcfile
+        done
+
+`,
+	Run: func(cmd *cobra.Command, args []string) {
+		autocompleteTarget := getFlagString(cmd, "file")
+		autocompleteType := getFlagString(cmd, "type")
+
+		if autocompleteType != "bash" {
+			checkError(fmt.Errorf("only Bash is supported for now"))
+		}
+
+		dir := filepath.Dir(autocompleteTarget)
+		ok, err := pathutil.DirExists(dir)
+		checkError(err)
+		if !ok {
+			os.MkdirAll(dir, 0744)
+		}
+		checkError(cmd.Root().GenBashCompletionFile(autocompleteTarget))
+
+		log.Infof("bash completion file for taxonkit saved to %s", autocompleteTarget)
+	},
+}
+
+func init() {
+	RootCmd.AddCommand(genautocompleteCmd)
+	defaultCompletionFile, err := homedir.Expand("~/.bash_completion.d/taxonkit.sh")
+	checkError(err)
+	genautocompleteCmd.Flags().StringP("file", "", defaultCompletionFile, "autocompletion file")
+	genautocompleteCmd.Flags().StringP("type", "", "bash", "autocompletion type (currently only bash supported)")
+}
diff --git a/taxonkit/cmd/helper.go b/taxonkit/cmd/helper.go
index 517e64b..4b43130 100644
--- a/taxonkit/cmd/helper.go
+++ b/taxonkit/cmd/helper.go
@@ -31,7 +31,7 @@ import (
 )
 
 // VERSION of csvtk
-const VERSION = "0.2.0"
+const VERSION = "0.2.1"
 
 // Config is the struct containing all global flags
 type Config struct {
diff --git a/taxonkit/cmd/list.go b/taxonkit/cmd/list.go
index e47f4e4..29477ff 100644
--- a/taxonkit/cmd/list.go
+++ b/taxonkit/cmd/list.go
@@ -86,6 +86,7 @@ var listCmd = &cobra.Command{
 					tree[parent] = make(map[int32]bool)
 				}
 				tree[parent][child] = false
+				tree[child] = make(map[int32]bool)
 				if printRank {
 					ranks[child] = info.rank
 				}
diff --git a/taxonkit/taxids.txt b/taxonkit/taxids.txt
index 4e52179..0751013 100644
--- a/taxonkit/taxids.txt
+++ b/taxonkit/taxids.txt
@@ -1,4 +1,5 @@
 9606
+9913
 349741
 239935
 11932