diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 71dc5c49..398628b7 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -63,8 +63,6 @@ jobs:
         - ubuntu
         - macOS
         go:
-        - 15
-        - 16
         - 17
         - 18
         - 19
@@ -81,12 +79,8 @@ jobs:
 
     - run: |
         export GOBIN=$HOME/go/bin
-        case "${{ matrix.go }}" in
-          14|15) _version='';;
-          *) _version='@latest';;
-        esac
-        go install github.com/kyoh86/richgo"${_version}"
-        go install github.com/mitchellh/gox"${_version}"
+        go install github.com/kyoh86/richgo@latest
+        go install github.com/mitchellh/gox@latest
 
     - run: RICHGO_FORCE_COLOR=1 PATH=$HOME/go/bin/:$PATH make richtest
 
diff --git a/go.mod b/go.mod
index a1309e53..6fe1b68f 100644
--- a/go.mod
+++ b/go.mod
@@ -1,6 +1,6 @@
 module github.com/spf13/cobra
 
-go 1.15
+go 1.17
 
 require (
 	github.com/cpuguy83/go-md2man/v2 v2.0.2
@@ -8,3 +8,5 @@ require (
 	github.com/spf13/pflag v1.0.5
 	gopkg.in/yaml.v3 v3.0.1
 )
+
+require github.com/russross/blackfriday/v2 v2.1.0 // indirect