diff --git a/cmd/fitactivity/combiner/combiner.go b/cmd/fitactivity/combiner/combiner.go
index e088a0a7..388f682f 100644
--- a/cmd/fitactivity/combiner/combiner.go
+++ b/cmd/fitactivity/combiner/combiner.go
@@ -8,6 +8,8 @@ import (
 	"fmt"
 	"time"
 
+	"slices"
+
 	"github.com/muktihari/fit/cmd/fitactivity/aggregator"
 	"github.com/muktihari/fit/factory"
 	"github.com/muktihari/fit/kit/datetime"
@@ -17,7 +19,6 @@ import (
 	"github.com/muktihari/fit/profile/untyped/fieldnum"
 	"github.com/muktihari/fit/profile/untyped/mesgnum"
 	"github.com/muktihari/fit/proto"
-	"golang.org/x/exp/slices"
 )
 
 type errorString string
diff --git a/cmd/fitactivity/combiner/combiner_test.go b/cmd/fitactivity/combiner/combiner_test.go
index 4baec1a8..dc0c4cd1 100644
--- a/cmd/fitactivity/combiner/combiner_test.go
+++ b/cmd/fitactivity/combiner/combiner_test.go
@@ -10,6 +10,8 @@ import (
 	"testing"
 	"time"
 
+	"slices"
+
 	"github.com/google/go-cmp/cmp"
 	"github.com/muktihari/fit/factory"
 	"github.com/muktihari/fit/kit/datetime"
@@ -19,7 +21,6 @@ import (
 	"github.com/muktihari/fit/profile/untyped/fieldnum"
 	"github.com/muktihari/fit/profile/untyped/mesgnum"
 	"github.com/muktihari/fit/proto"
-	"golang.org/x/exp/slices"
 )
 
 func TestCombine(t *testing.T) {
diff --git a/go.mod b/go.mod
index 543ccbfc..571fdceb 100644
--- a/go.mod
+++ b/go.mod
@@ -1,13 +1,12 @@
 module github.com/muktihari/fit
 
-go 1.20
+go 1.21
 
 require (
 	github.com/client9/misspell v0.3.4
 	github.com/google/go-cmp v0.6.0
 	github.com/muktihari/carto v0.1.1
 	github.com/thedatashed/xlsxreader v1.2.8
-	golang.org/x/exp v0.0.0-20240531132922-fd00a4e0eefc
 	golang.org/x/text v0.18.0
 )
 
diff --git a/go.sum b/go.sum
index bda533fc..3bd691e8 100644
--- a/go.sum
+++ b/go.sum
@@ -2,6 +2,7 @@ github.com/client9/misspell v0.3.4 h1:ta993UF76GwbvJcIo3Y68y/M3WxlpEHPWIGDkJYwzJ
 github.com/client9/misspell v0.3.4/go.mod h1:qj6jICC3Q7zFZvVWo7KLAzC3yx5G7kyvSDkc90ppPyw=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/google/go-cmp v0.6.0 h1:ofyhxvXcZhMsU5ulbFiLKl/XBFqE1GSq7atu8tAmTRI=
 github.com/google/go-cmp v0.6.0/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
 github.com/muktihari/carto v0.1.1 h1:2onp1tC7uYLBQy5WuIJyP5A6oQq3duRkcO3kf6+hzR0=
@@ -14,8 +15,7 @@ github.com/stretchr/testify v1.9.0 h1:HtqpIVDClZ4nwg75+f6Lvsy/wHu+3BoSGCbBAcpTsT
 github.com/stretchr/testify v1.9.0/go.mod h1:r2ic/lqez/lEtzL7wO/rwa5dbSLXVDPFyf8C91i36aY=
 github.com/thedatashed/xlsxreader v1.2.8 h1:8aGbkXIPEThQbA8KzUZqIa4v4oqFrJFKLQ36vWePI5U=
 github.com/thedatashed/xlsxreader v1.2.8/go.mod h1:wZyb/2xF1+rkZ2ujhC72tuuOWBY574QvcXHFls+5AXc=
-golang.org/x/exp v0.0.0-20240531132922-fd00a4e0eefc h1:O9NuF4s+E/PvMIy+9IUZB9znFwUIXEWSstNjek6VpVg=
-golang.org/x/exp v0.0.0-20240531132922-fd00a4e0eefc/go.mod h1:XtvwrStGgqGPLc4cjQfWqZHG1YFdYs6swckp8vpsjnc=
 golang.org/x/text v0.18.0 h1:XvMDiNzPAl0jr17s6W9lcaIhGUfUORdGCNsuLmPG224=
 golang.org/x/text v0.18.0/go.mod h1:BuEKDfySbSR4drPmRPG/7iBdf8hvFMuRexcpahXilzY=
 gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
diff --git a/internal/cmd/benchfit/go.mod b/internal/cmd/benchfit/go.mod
index d1da9d2d..08d68b37 100644
--- a/internal/cmd/benchfit/go.mod
+++ b/internal/cmd/benchfit/go.mod
@@ -1,6 +1,6 @@
 module benchfit
 
-go 1.20
+go 1.21
 
 require (
 	github.com/muktihari/fit v0.0.0
diff --git a/internal/cmd/fitgen/pkg/flagutil/flagutil.go b/internal/cmd/fitgen/pkg/flagutil/flagutil.go
index e127cb42..30980503 100644
--- a/internal/cmd/fitgen/pkg/flagutil/flagutil.go
+++ b/internal/cmd/fitgen/pkg/flagutil/flagutil.go
@@ -10,7 +10,7 @@ import (
 	"os"
 	"strings"
 
-	"golang.org/x/exp/slices"
+	"slices"
 )
 
 func Usage() {
diff --git a/internal/cmd/fitgen/pkg/strutil/strutil_test.go b/internal/cmd/fitgen/pkg/strutil/strutil_test.go
index 62d51ba9..2f4c9d55 100644
--- a/internal/cmd/fitgen/pkg/strutil/strutil_test.go
+++ b/internal/cmd/fitgen/pkg/strutil/strutil_test.go
@@ -5,11 +5,47 @@
 package strutil_test
 
 import (
+	"fmt"
 	"testing"
 
 	"github.com/muktihari/fit/internal/cmd/fitgen/pkg/strutil"
 )
 
+func BenchmarkToTitle(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		_ = strutil.ToTitle("avg_speed")
+	}
+}
+
+func TestToTitle(t *testing.T) {
+	tt := []struct {
+		input  string
+		output string
+	}{
+		{
+			input:  "avg_speed",
+			output: "AvgSpeed",
+		},
+		{
+			input:  "avg speed",
+			output: "AvgSpeed",
+		},
+		{
+			input:  "timestamp_32k",
+			output: "Timestamp32K",
+		},
+	}
+
+	for i, tc := range tt {
+		t.Run(fmt.Sprintf("[%d] %s", i, tc.input), func(t *testing.T) {
+			out := strutil.ToTitle(tc.input)
+			if out != tc.output {
+				t.Fatalf("expected: %q, got: %q", tc.output, out)
+			}
+		})
+	}
+}
+
 func TestTrimRepeatedChar(t *testing.T) {
 	tt := []struct {
 		s string
diff --git a/internal/cmd/fitgen/profile/mesgdef/builder.go b/internal/cmd/fitgen/profile/mesgdef/builder.go
index 40eb50fa..e617f0f6 100644
--- a/internal/cmd/fitgen/profile/mesgdef/builder.go
+++ b/internal/cmd/fitgen/profile/mesgdef/builder.go
@@ -12,12 +12,13 @@ import (
 	"strings"
 	"text/template"
 
+	"slices"
+
 	"github.com/muktihari/fit/internal/cmd/fitgen/generator"
 	"github.com/muktihari/fit/internal/cmd/fitgen/lookup"
 	"github.com/muktihari/fit/internal/cmd/fitgen/parser"
 	"github.com/muktihari/fit/internal/cmd/fitgen/pkg/strutil"
 	"github.com/muktihari/fit/profile/basetype"
-	"golang.org/x/exp/slices"
 )
 
 type Builder struct {
diff --git a/internal/cmd/fitgen/profile/untyped/fieldnum/builder.go b/internal/cmd/fitgen/profile/untyped/fieldnum/builder.go
index b2064a94..0479050b 100644
--- a/internal/cmd/fitgen/profile/untyped/fieldnum/builder.go
+++ b/internal/cmd/fitgen/profile/untyped/fieldnum/builder.go
@@ -12,12 +12,13 @@ import (
 	"strings"
 	"text/template"
 
+	"slices"
+
 	"github.com/muktihari/fit/internal/cmd/fitgen/generator"
 	"github.com/muktihari/fit/internal/cmd/fitgen/lookup"
 	"github.com/muktihari/fit/internal/cmd/fitgen/parser"
 	"github.com/muktihari/fit/internal/cmd/fitgen/pkg/strutil"
 	"github.com/muktihari/fit/internal/cmd/fitgen/shared"
-	"golang.org/x/exp/slices"
 )
 
 type Builder struct {
diff --git a/kit/scaleoffset/scaleoffset.go b/kit/scaleoffset/scaleoffset.go
index f83bea17..227dea32 100644
--- a/kit/scaleoffset/scaleoffset.go
+++ b/kit/scaleoffset/scaleoffset.go
@@ -7,11 +7,10 @@ package scaleoffset
 import (
 	"github.com/muktihari/fit/profile/basetype"
 	"github.com/muktihari/fit/proto"
-	"golang.org/x/exp/constraints"
 )
 
 type Numeric interface {
-	constraints.Integer | constraints.Float
+	~int8 | ~int16 | ~int32 | ~int64 | ~uint8 | ~uint16 | ~uint32 | ~uint64 | ~float32 | ~float64
 }
 
 // Apply applies scale and offset on value.
diff --git a/profile/filedef/activity_test.go b/profile/filedef/activity_test.go
index ace500ed..033fd04d 100644
--- a/profile/filedef/activity_test.go
+++ b/profile/filedef/activity_test.go
@@ -9,6 +9,8 @@ import (
 	"testing"
 	"time"
 
+	"slices"
+
 	"github.com/google/go-cmp/cmp"
 	"github.com/muktihari/fit/factory"
 	"github.com/muktihari/fit/kit/datetime"
@@ -18,7 +20,6 @@ import (
 	"github.com/muktihari/fit/profile/untyped/fieldnum"
 	"github.com/muktihari/fit/profile/untyped/mesgnum"
 	"github.com/muktihari/fit/proto"
-	"golang.org/x/exp/slices"
 )
 
 func sortFields(mesgs []proto.Message) {
diff --git a/profile/filedef/filedef.go b/profile/filedef/filedef.go
index b21b0662..297161fb 100644
--- a/profile/filedef/filedef.go
+++ b/profile/filedef/filedef.go
@@ -5,11 +5,12 @@
 package filedef
 
 import (
+	"slices"
+
 	"github.com/muktihari/fit/profile/mesgdef"
 	"github.com/muktihari/fit/profile/untyped/fieldnum"
 	"github.com/muktihari/fit/profile/untyped/mesgnum"
 	"github.com/muktihari/fit/proto"
-	"golang.org/x/exp/slices"
 )
 
 // File is an interface for defining common type file, any defined common file type should implement