diff --git a/go.mod b/go.mod
index 0654ade..2bd9411 100644
--- a/go.mod
+++ b/go.mod
@@ -1,11 +1,8 @@
 module github.com/nulab/autog
 
-go 1.21
+go 1.22
 
-require (
-	github.com/stretchr/testify v1.8.4
-	golang.org/x/exp v0.0.0-20230807204917-050eac23e9de
-)
+require github.com/stretchr/testify v1.8.4
 
 require (
 	github.com/davecgh/go-spew v1.1.1 // indirect
diff --git a/go.sum b/go.sum
index 47d43dd..fa4b6e6 100644
--- a/go.sum
+++ b/go.sum
@@ -4,8 +4,6 @@ github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZb
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/stretchr/testify v1.8.4 h1:CcVxjf3Q8PM0mHUKJCdn+eZZtm5yQwehR5yeSVQQcUk=
 github.com/stretchr/testify v1.8.4/go.mod h1:sz/lmYIOXD/1dqDmKjjqLyZ2RngseejIcXlSw2iwfAo=
-golang.org/x/exp v0.0.0-20230807204917-050eac23e9de h1:l5Za6utMv/HsBWWqzt4S8X17j+kt1uVETUX5UFhn2rE=
-golang.org/x/exp v0.0.0-20230807204917-050eac23e9de/go.mod h1:FXUEEKJgO7OQYeo8N01OfiKP8RXMtf6e8aTskBGqWdc=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
diff --git a/internal/num/abs.go b/internal/num/abs.go
index 903efb1..2a1e2c5 100644
--- a/internal/num/abs.go
+++ b/internal/num/abs.go
@@ -1,8 +1,18 @@
 package num
 
-import "golang.org/x/exp/constraints"
+type Signed interface {
+	~int | ~int8 | ~int16 | ~int32 | ~int64
+}
+
+type Unsigned interface {
+	~uint | ~uint8 | ~uint16 | ~uint32 | ~uint64 | ~uintptr
+}
+
+type Integer interface {
+	Signed | Unsigned
+}
 
-func Abs[T constraints.Integer](x T) T {
+func Abs[T Integer](x T) T {
 	if x < 0 {
 		return -x
 	}