diff --git a/cmd/root.go b/cmd/root.go
index 2a324c4a..d889cb47 100644
--- a/cmd/root.go
+++ b/cmd/root.go
@@ -23,6 +23,7 @@ package cmd
 
 import (
 	"fmt"
+	"io"
 	"os"
 	"strings"
 
@@ -114,11 +115,11 @@ func initLogging() {
 }
 
 // Completion
-var completionFunctions = map[string]interface{}{
-	"bash":       rootCmd.GenBashCompletion(os.Stdout),
-	"zsh":        rootCmd.GenZshCompletion(os.Stdout),
-	"psh":        rootCmd.GenPowerShellCompletion(os.Stdout),
-	"powershell": rootCmd.GenPowerShellCompletion(os.Stdout),
+var completionFunctions = map[string]func(io.Writer) error{
+	"bash":       rootCmd.GenBashCompletion,
+	"zsh":        rootCmd.GenZshCompletion,
+	"psh":        rootCmd.GenPowerShellCompletion,
+	"powershell": rootCmd.GenPowerShellCompletion,
 }
 
 // NewCmdCompletion creates a new completion command
@@ -132,7 +133,7 @@ func NewCmdCompletion() *cobra.Command {
 		Args:  cobra.ExactArgs(1), // TODO: add support for 0 args = auto detection
 		Run: func(cmd *cobra.Command, args []string) {
 			if f, ok := completionFunctions[args[0]]; ok {
-				if err := f; err != nil {
+				if err := f(os.Stdout); err != nil {
 					log.Fatalf("Failed to generate completion script for shell '%s'", args[0])
 				}
 				return
diff --git a/go.mod b/go.mod
index 26fe29f4..831d9781 100644
--- a/go.mod
+++ b/go.mod
@@ -6,8 +6,6 @@ require (
 	github.com/Azure/go-ansiterm v0.0.0-20170929234023-d6e3b3328b78 // indirect
 	github.com/Microsoft/go-winio v0.4.14 // indirect
 	github.com/Microsoft/hcsshim v0.8.6 // indirect
-	github.com/alecthomas/template v0.0.0-20190718012654-fb15b899a751 // indirect
-	github.com/alecthomas/units v0.0.0-20190924025748-f65c72e2690d // indirect
 	github.com/containerd/cgroups v0.0.0-20190923161937-abd0b19954a6 // indirect
 	github.com/containerd/containerd v1.3.0-rc.2.0.20190924150618-aba201344ebf
 	github.com/containerd/continuity v0.0.0-20190827140505-75bee3e2ccb6 // indirect
@@ -33,6 +31,7 @@ require (
 	github.com/opencontainers/runtime-spec v1.0.1 // indirect
 	github.com/sirupsen/logrus v1.4.2
 	github.com/spf13/cobra v0.0.5
+	github.com/stretchr/testify v1.4.0 // indirect
 	github.com/syndtr/gocapability v0.0.0-20180916011248-d98352740cb2 // indirect
 	go.etcd.io/bbolt v1.3.3 // indirect
 	golang.org/x/net v0.0.0-20190812203447-cdfb69ac37fc // indirect
@@ -40,7 +39,6 @@ require (
 	golang.org/x/text v0.3.2 // indirect
 	golang.org/x/time v0.0.0-20190308202827-9d24e82272b4 // indirect
 	google.golang.org/grpc v1.23.0 // indirect
-	gopkg.in/alecthomas/kingpin.v2 v2.2.6 // indirect
 	gopkg.in/check.v1 v1.0.0-20190902080502-41f04d3bba15 // indirect
 	gotest.tools v2.2.0+incompatible // indirect
 )
diff --git a/go.sum b/go.sum
index 276b5277..fcb031a0 100644
--- a/go.sum
+++ b/go.sum
@@ -11,10 +11,6 @@ github.com/Microsoft/go-winio v0.4.14/go.mod h1:qXqCSQ3Xa7+6tgxaGTIe4Kpcdsi+P8jB
 github.com/Microsoft/hcsshim v0.8.6 h1:ZfF0+zZeYdzMIVMZHKtDKJvLHj76XCuVae/jNkjj0IA=
 github.com/Microsoft/hcsshim v0.8.6/go.mod h1:Op3hHsoHPAvb6lceZHDtd9OkTew38wNoXnJs8iY7rUg=
 github.com/Shopify/logrus-bugsnag v0.0.0-20171204204709-577dee27f20d/go.mod h1:HI8ITrYtUY+O+ZhtlqUnD8+KwNPOyugEhfP9fdUIaEQ=
-github.com/alecthomas/template v0.0.0-20190718012654-fb15b899a751 h1:JYp7IbQjafoB+tBA3gMyHYHrpOtNuDiK/uB5uXxq5wM=
-github.com/alecthomas/template v0.0.0-20190718012654-fb15b899a751/go.mod h1:LOuyumcjzFXgccqObfd/Ljyb9UuFJ6TxHnclSeseNhc=
-github.com/alecthomas/units v0.0.0-20190924025748-f65c72e2690d h1:UQZhZ2O0vMHr2cI+DC1Mbh0TJxzA3RcLoMsFw+aXw7E=
-github.com/alecthomas/units v0.0.0-20190924025748-f65c72e2690d/go.mod h1:rBZYJk541a8SKzHPHnH3zbiI+7dagKZ0cgpgrD7Fyho=
 github.com/armon/consul-api v0.0.0-20180202201655-eb2c6b5be1b6/go.mod h1:grANhF5doyWs3UAsr3K4I6qtAmlQcZDesFNEHPZAzj8=
 github.com/aws/aws-sdk-go v1.15.11/go.mod h1:mFuSZ37Z9YOHbQEwBWztmVzqXrEkub65tZoCYDt7FT0=
 github.com/beorn7/perks v0.0.0-20160804104726-4c0e84591b9a/go.mod h1:Dwedo/Wpr24TaqPxmxbtue+5NUziq4I4S80YR8gNf3Q=
@@ -231,8 +227,6 @@ google.golang.org/genproto v0.0.0-20180817151627-c66870c02cf8/go.mod h1:JiN7NxoA
 google.golang.org/grpc v0.0.0-20160317175043-d3ddb4469d5a/go.mod h1:yo6s7OP7yaDglbqo1J04qKzAhqBH6lvTonzMVmEdcZw=
 google.golang.org/grpc v1.23.0 h1:AzbTB6ux+okLTzP8Ru1Xs41C303zdcfEht7MQnYJt5A=
 google.golang.org/grpc v1.23.0/go.mod h1:Y5yQAOtifL1yxbo5wqy6BxZv8vAUGQwXBOALyacEbxg=
-gopkg.in/alecthomas/kingpin.v2 v2.2.6 h1:jMFz6MfLP0/4fUyZle81rXUoxOBFi19VUFKVDOQfozc=
-gopkg.in/alecthomas/kingpin.v2 v2.2.6/go.mod h1:FMv+mEhP44yOT+4EoQTLFTRgOQ1FBLkstjWtayDeSgw=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/check.v1 v1.0.0-20141024133853-64131543e789/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/check.v1 v1.0.0-20190902080502-41f04d3bba15 h1:YR8cESwS4TdDjEe65xsg0ogRM/Nc3DYOhEAlW+xobZo=