diff --git a/go.mod b/go.mod
index 715f4b85..8cf6b938 100644
--- a/go.mod
+++ b/go.mod
@@ -4,7 +4,8 @@ go 1.17
 
 require (
 	github.com/sirupsen/logrus v1.7.0
-	golang.org/x/sys v0.0.0-20220422013727-9388b58f7150
+	golang.org/x/sys v0.0.0-20220722155257-8c9f86f7a55f
+	golang.org/x/tools v0.1.12
 )
 
-require golang.org/x/sync v0.0.0-20220722155255-886fb9371eb4 // indirect
+require golang.org/x/mod v0.6.0-dev.0.20220419223038-86c51ed26bb4 // indirect
diff --git a/go.sum b/go.sum
index 7ec6d7ce..3583d96f 100644
--- a/go.sum
+++ b/go.sum
@@ -6,8 +6,30 @@ github.com/sirupsen/logrus v1.7.0 h1:ShrD1U9pZB12TX0cVy0DtePoCH97K8EtX+mg7ZARUtM
 github.com/sirupsen/logrus v1.7.0/go.mod h1:yWOB1SBYBC5VeMP7gHvWumXLIWorT60ONWic61uBYv0=
 github.com/stretchr/testify v1.2.2 h1:bSDNvY7ZPG5RlJ8otE/7V6gMiyenm9RtJ7IUVIAoJ1w=
 github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=
-golang.org/x/sync v0.0.0-20220722155255-886fb9371eb4 h1:uVc8UZUe6tr40fFVnUP5Oj+veunVezqYl9z7DYw9xzw=
+github.com/yuin/goldmark v1.4.13/go.mod h1:6yULJ656Px+3vBD8DxQVa3kxgyrAnzto9xy5taEt/CY=
+golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
+golang.org/x/crypto v0.0.0-20210921155107-089bfa567519/go.mod h1:GvvjBRRGRdwPK5ydBHafDWAxML/pGHZbMvKqRZ5+Abc=
+golang.org/x/mod v0.6.0-dev.0.20220419223038-86c51ed26bb4 h1:6zppjxzCulZykYSLyVDYbneBfbaBIQPYMevg0bEwv2s=
+golang.org/x/mod v0.6.0-dev.0.20220419223038-86c51ed26bb4/go.mod h1:jJ57K6gSWd91VN4djpZkiMVwK6gcyfeH4XE8wZrZaV4=
+golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
+golang.org/x/net v0.0.0-20210226172049-e18ecbb05110/go.mod h1:m0MpNAwzfU5UDzcl9v0D8zg8gWTRqZa9RBIspLL5mdg=
+golang.org/x/net v0.0.0-20220722155237-a158d28d115b/go.mod h1:XRhObCWvk6IyKnWLug+ECip1KBveYUHfp+8e9klMJ9c=
+golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20220722155255-886fb9371eb4/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20191026070338-33540a1f6037/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20220422013727-9388b58f7150 h1:xHms4gcpe1YE7A3yIllJXP16CMAGuqwO2lX1mTyyRRc=
-golang.org/x/sys v0.0.0-20220422013727-9388b58f7150/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20210615035016-665e8c7367d1/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.0.0-20220520151302-bc2c85ada10a/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.0.0-20220722155257-8c9f86f7a55f h1:v4INt8xihDGvnrfjMDVXGxw9wrfxYyCjk0KbXjhR55s=
+golang.org/x/sys v0.0.0-20220722155257-8c9f86f7a55f/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
+golang.org/x/term v0.0.0-20210927222741-03fcf44c2211/go.mod h1:jbD1KX2456YbFQfuXm/mYQcufACuNUgVhRMnK/tPxf8=
+golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
+golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
+golang.org/x/text v0.3.7/go.mod h1:u+2+/6zg+i71rQMx5EYifcz6MCKuco9NR6JIITiCfzQ=
+golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
+golang.org/x/tools v0.0.0-20191119224855-298f0cb1881e/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
+golang.org/x/tools v0.1.12 h1:VveCTK38A2rkS8ZqFY25HIDFscX5X9OoEhJd3quQmXU=
+golang.org/x/tools v0.1.12/go.mod h1:hNGJHUnrk76NpqgfD5Aqm5Crs+Hm0VOH/i9J2+nxYbc=
+golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
diff --git a/pkg/guid/guid.go b/pkg/guid/guid.go
index 7e8e60b1..48ce4e92 100644
--- a/pkg/guid/guid.go
+++ b/pkg/guid/guid.go
@@ -14,17 +14,19 @@ import (
 	"strconv"
 )
 
+//go:generate go run golang.org/x/tools/cmd/stringer -type=Variant -trimprefix=Variant -linecomment
+
 // Variant specifies which GUID variant (or "type") of the GUID. It determines
 // how the entirety of the rest of the GUID is interpreted.
 type Variant uint8
 
-// The variants specified by RFC 4122.
+// The variants specified by RFC 4122 section 4.1.1.
 const (
 	// VariantUnknown specifies a GUID variant which does not conform to one of
 	// the variant encodings specified in RFC 4122.
 	VariantUnknown Variant = iota
 	VariantNCS
-	VariantRFC4122
+	VariantRFC4122 // RFC 4122
 	VariantMicrosoft
 	VariantFuture
 )
@@ -34,6 +36,10 @@ const (
 // hash of an input string.
 type Version uint8
 
+func (v Version) String() string {
+	return strconv.FormatUint(uint64(v), 10)
+}
+
 var _ = (encoding.TextMarshaler)(GUID{})
 var _ = (encoding.TextUnmarshaler)(&GUID{})
 
diff --git a/pkg/guid/guid_test.go b/pkg/guid/guid_test.go
index d7e21241..91ac0e68 100644
--- a/pkg/guid/guid_test.go
+++ b/pkg/guid/guid_test.go
@@ -46,27 +46,29 @@ func Test_Variant(t *testing.T) {
 		{mustFromString(t, "f5cbc1a9-4cba-45a0-ffdd-b6761fc7dcc0"), VariantFuture},
 	}
 	for _, tc := range testCases {
-		actualVariant := tc.g.Variant()
-		if actualVariant != tc.v {
-			t.Fatalf("Variant is not correct.\nExpected: %d\nActual: %d\nGUID: %s", tc.v, actualVariant, tc.g)
-		}
+		t.Run(tc.v.String()+"/"+tc.g.String(), func(t *testing.T) {
+			actualVariant := tc.g.Variant()
+			if actualVariant != tc.v {
+				t.Fatalf("Variant is not correct.\nExpected: %d\nActual: %d\nGUID: %s", tc.v, actualVariant, tc.g)
+			}
+		})
 	}
 }
 
 func Test_SetVariant(t *testing.T) {
-	testCases := []Variant{
-		VariantNCS,
-		VariantRFC4122,
-		VariantMicrosoft,
-		VariantFuture,
-	}
 	g := mustFromString(t, "f5cbc1a9-4cba-45a0-bfdd-b6761fc7dcc0")
-	for _, tc := range testCases {
-		t.Logf("Test case: %d", tc)
-		g.setVariant(tc)
-		if g.Variant() != tc {
-			t.Fatalf("Variant is incorrect.\nExpected: %d\nActual: %d", tc, g.Variant())
+	for i := 0; i < len(_Variant_index)-1; i++ {
+		v := Variant(i)
+		if v == VariantUnknown {
+			// Unknown is not a valid variant
+			continue
 		}
+		t.Run(v.String(), func(t *testing.T) {
+			g.setVariant(v)
+			if g.Variant() != v {
+				t.Fatalf("Variant is incorrect.\nExpected: %d\nActual: %d", v, g.Variant())
+			}
+		})
 	}
 }
 
@@ -83,22 +85,25 @@ func Test_Version(t *testing.T) {
 		{mustFromString(t, "f5cbc1a9-4cba-55a0-0fdd-b6761fc7dcc0"), 5},
 	}
 	for _, tc := range testCases {
-		actualVersion := tc.g.Version()
-		if actualVersion != tc.v {
-			t.Fatalf("Version is not correct.\nExpected: %d\nActual: %d\nGUID: %s", tc.v, actualVersion, tc.g)
-		}
+		t.Run(tc.v.String()+"-"+tc.g.String(), func(t *testing.T) {
+			actualVersion := tc.g.Version()
+			if actualVersion != tc.v {
+				t.Fatalf("Version is not correct.\nExpected: %d\nActual: %d\nGUID: %s", tc.v, actualVersion, tc.g)
+			}
+		})
 	}
 }
 
 func Test_SetVersion(t *testing.T) {
 	g := mustFromString(t, "f5cbc1a9-4cba-45a0-bfdd-b6761fc7dcc0")
 	for tc := 0; tc < 16; tc++ {
-		t.Logf("Test case: %d", tc)
 		v := Version(tc)
-		g.setVersion(v)
-		if g.Version() != v {
-			t.Fatalf("Version is incorrect.\nExpected: %d\nActual: %d", v, g.Version())
-		}
+		t.Run(v.String(), func(t *testing.T) {
+			g.setVersion(v)
+			if g.Version() != v {
+				t.Fatalf("Version is incorrect.\nExpected: %d\nActual: %d", v, g.Version())
+			}
+		})
 	}
 }
 
@@ -160,10 +165,12 @@ func Test_V5KnownValues(t *testing.T) {
 		},
 	}
 	for _, tc := range testCases {
-		g := mustNewV5(t, tc.ns, []byte(tc.name))
-		if g != tc.g {
-			t.Fatalf("GUIDs are not equal.\nExpected: %s\nActual: %s", tc.g, g)
-		}
+		t.Run(tc.name, func(t *testing.T) {
+			g := mustNewV5(t, tc.ns, []byte(tc.name))
+			if g != tc.g {
+				t.Fatalf("GUIDs are not equal.\nExpected: %s\nActual: %s", tc.g, g)
+			}
+		})
 	}
 }
 
diff --git a/pkg/guid/variant_string.go b/pkg/guid/variant_string.go
new file mode 100644
index 00000000..4076d313
--- /dev/null
+++ b/pkg/guid/variant_string.go
@@ -0,0 +1,27 @@
+// Code generated by "stringer -type=Variant -trimprefix=Variant -linecomment"; DO NOT EDIT.
+
+package guid
+
+import "strconv"
+
+func _() {
+	// An "invalid array index" compiler error signifies that the constant values have changed.
+	// Re-run the stringer command to generate them again.
+	var x [1]struct{}
+	_ = x[VariantUnknown-0]
+	_ = x[VariantNCS-1]
+	_ = x[VariantRFC4122-2]
+	_ = x[VariantMicrosoft-3]
+	_ = x[VariantFuture-4]
+}
+
+const _Variant_name = "UnknownNCSRFC 4122MicrosoftFuture"
+
+var _Variant_index = [...]uint8{0, 7, 10, 18, 27, 33}
+
+func (i Variant) String() string {
+	if i >= Variant(len(_Variant_index)-1) {
+		return "Variant(" + strconv.FormatInt(int64(i), 10) + ")"
+	}
+	return _Variant_name[_Variant_index[i]:_Variant_index[i+1]]
+}
diff --git a/tools.go b/tools.go
new file mode 100644
index 00000000..2aa04584
--- /dev/null
+++ b/tools.go
@@ -0,0 +1,5 @@
+//go:build tools
+
+package winio
+
+import _ "golang.org/x/tools/cmd/stringer"