diff --git a/go.mod b/go.mod
index af458ca..ab59f68 100644
--- a/go.mod
+++ b/go.mod
@@ -1,5 +1,11 @@
 module github.com/pete911/ipcalc
 
-go 1.16
+go 1.17
 
 require github.com/stretchr/testify v1.7.0
+
+require (
+	github.com/davecgh/go-spew v1.1.0 // indirect
+	github.com/pmezard/go-difflib v1.0.0 // indirect
+	gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c // indirect
+)
diff --git a/vendor/gopkg.in/yaml.v3/go.mod b/vendor/gopkg.in/yaml.v3/go.mod
deleted file mode 100644
index f407ea3..0000000
--- a/vendor/gopkg.in/yaml.v3/go.mod
+++ /dev/null
@@ -1,5 +0,0 @@
-module "gopkg.in/yaml.v3"
-
-require (
-	"gopkg.in/check.v1" v0.0.0-20161208181325-20d25e280405
-)
diff --git a/vendor/modules.txt b/vendor/modules.txt
index cfb1ad3..a52dc6a 100644
--- a/vendor/modules.txt
+++ b/vendor/modules.txt
@@ -1,10 +1,13 @@
 # github.com/davecgh/go-spew v1.1.0
+## explicit
 github.com/davecgh/go-spew/spew
 # github.com/pmezard/go-difflib v1.0.0
+## explicit
 github.com/pmezard/go-difflib/difflib
 # github.com/stretchr/testify v1.7.0
-## explicit
+## explicit; go 1.13
 github.com/stretchr/testify/assert
 github.com/stretchr/testify/require
 # gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c
+## explicit
 gopkg.in/yaml.v3