diff --git a/.github/workflows/benchmark.yml b/.github/workflows/benchmark.yml
index 1bd2c95..1ec1dfb 100644
--- a/.github/workflows/benchmark.yml
+++ b/.github/workflows/benchmark.yml
@@ -40,7 +40,7 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-      - name: Steup Go
+      - name: Setup Go
         uses: actions/setup-go@v2
         with:
           go-version: "1.24"
diff --git a/.golangci.yml b/.golangci.yml
new file mode 100644
index 0000000..01db160
--- /dev/null
+++ b/.golangci.yml
@@ -0,0 +1,7 @@
+version: "2"
+linters:
+  exclusions:
+    rules:
+      # Tests copied from the stdlib are not meant to be linted.
+      - path: 'golang_(.+_)?test\.go'
+        source: "^" # regex
diff --git a/benchmarks/Makefile b/benchmarks/Makefile
index e14cb3e..8b36507 100644
--- a/benchmarks/Makefile
+++ b/benchmarks/Makefile
@@ -74,7 +74,7 @@ benchstat := ${GOPATH}/bin/benchstat
 all:
 
 $(benchstat):
-	go install golang.org/x/perf/cmd/benchstat
+	go install golang.org/x/perf/cmd/benchstat@latest
 
 $(benchmark.cmd.dir)/message.pb.go: $(benchmark.cmd.dir)/message.proto
 	@protoc -I. \
diff --git a/json/codec.go b/json/codec.go
index 32c078f..77fe264 100644
--- a/json/codec.go
+++ b/json/codec.go
@@ -4,6 +4,7 @@ import (
 	"encoding"
 	"encoding/json"
 	"fmt"
+	"maps"
 	"math/big"
 	"reflect"
 	"sort"
@@ -73,12 +74,9 @@ func cacheLoad() map[unsafe.Pointer]codec {
 
 func cacheStore(typ reflect.Type, cod codec, oldCodecs map[unsafe.Pointer]codec) {
 	newCodecs := make(map[unsafe.Pointer]codec, len(oldCodecs)+1)
+	maps.Copy(newCodecs, oldCodecs)
 	newCodecs[typeid(typ)] = cod
 
-	for t, c := range oldCodecs {
-		newCodecs[t] = c
-	}
-
 	cache.Store(&newCodecs)
 }
 
@@ -205,7 +203,7 @@ func constructCodec(t reflect.Type, seen map[reflect.Type]*structType, canAddr b
 		c = constructUnsupportedTypeCodec(t)
 	}
 
-	p := reflect.PtrTo(t)
+	p := reflect.PointerTo(t)
 
 	if canAddr {
 		switch {
@@ -291,7 +289,7 @@ func constructSliceCodec(t reflect.Type, seen map[reflect.Type]*structType) code
 		// Go 1.7+ behavior: slices of byte types (and aliases) may override the
 		// default encoding and decoding behaviors by implementing marshaler and
 		// unmarshaler interfaces.
-		p := reflect.PtrTo(e)
+		p := reflect.PointerTo(e)
 		c := codec{}
 
 		switch {
@@ -391,7 +389,7 @@ func constructMapCodec(t reflect.Type, seen map[reflect.Type]*structType) codec
 	kc := codec{}
 	vc := constructCodec(v, seen, false)
 
-	if k.Implements(textMarshalerType) || reflect.PtrTo(k).Implements(textUnmarshalerType) {
+	if k.Implements(textMarshalerType) || reflect.PointerTo(k).Implements(textUnmarshalerType) {
 		kc.encode = constructTextMarshalerEncodeFunc(k, false)
 		kc.decode = constructTextUnmarshalerDecodeFunc(k, true)
 
@@ -972,7 +970,6 @@ type structType struct {
 	ficaseIndex map[string]*structField
 	keyset      []byte
 	typ         reflect.Type
-	inlined     bool
 }
 
 type structField struct {
@@ -1095,10 +1092,10 @@ var (
 	timeType       = reflect.TypeOf(time.Time{})
 	rawMessageType = reflect.TypeOf(RawMessage(nil))
 
-	numberPtrType     = reflect.PtrTo(numberType)
-	durationPtrType   = reflect.PtrTo(durationType)
-	timePtrType       = reflect.PtrTo(timeType)
-	rawMessagePtrType = reflect.PtrTo(rawMessageType)
+	numberPtrType     = reflect.PointerTo(numberType)
+	durationPtrType   = reflect.PointerTo(durationType)
+	timePtrType       = reflect.PointerTo(timeType)
+	rawMessagePtrType = reflect.PointerTo(rawMessageType)
 
 	sliceInterfaceType       = reflect.TypeOf(([]any)(nil))
 	sliceStringType          = reflect.TypeOf(([]any)(nil))
diff --git a/json/decode.go b/json/decode.go
index b44dde6..c87f01e 100644
--- a/json/decode.go
+++ b/json/decode.go
@@ -1410,7 +1410,7 @@ func (d decoder) decodeMaybeEmptyInterface(b []byte, p unsafe.Pointer, t reflect
 	return d.decodeUnmarshalTypeError(b, p, t)
 }
 
-func (d decoder) decodeUnmarshalTypeError(b []byte, p unsafe.Pointer, t reflect.Type) ([]byte, error) {
+func (d decoder) decodeUnmarshalTypeError(b []byte, _ unsafe.Pointer, t reflect.Type) ([]byte, error) {
 	v, b, _, err := d.parseValue(b)
 	if err != nil {
 		return b, err
@@ -1500,7 +1500,7 @@ func (d decoder) decodeTextUnmarshaler(b []byte, p unsafe.Pointer, t reflect.Typ
 		value = "array"
 	}
 
-	return b, &UnmarshalTypeError{Value: value, Type: reflect.PtrTo(t)}
+	return b, &UnmarshalTypeError{Value: value, Type: reflect.PointerTo(t)}
 }
 
 func (d decoder) prependField(key, field string) string {
diff --git a/json/json.go b/json/json.go
index 11ec69c..028fd1f 100644
--- a/json/json.go
+++ b/json/json.go
@@ -15,7 +15,7 @@ import (
 type Delim = json.Delim
 
 // InvalidUTF8Error is documented at https://golang.org/pkg/encoding/json/#InvalidUTF8Error
-type InvalidUTF8Error = json.InvalidUTF8Error
+type InvalidUTF8Error = json.InvalidUTF8Error //nolint:staticcheck // compat.
 
 // InvalidUnmarshalError is documented at https://golang.org/pkg/encoding/json/#InvalidUnmarshalError
 type InvalidUnmarshalError = json.InvalidUnmarshalError
@@ -39,7 +39,7 @@ type SyntaxError = json.SyntaxError
 type Token = json.Token
 
 // UnmarshalFieldError is documented at https://golang.org/pkg/encoding/json/#UnmarshalFieldError
-type UnmarshalFieldError = json.UnmarshalFieldError
+type UnmarshalFieldError = json.UnmarshalFieldError //nolint:staticcheck // compat.
 
 // UnmarshalTypeError is documented at https://golang.org/pkg/encoding/json/#UnmarshalTypeError
 type UnmarshalTypeError = json.UnmarshalTypeError
diff --git a/json/json_test.go b/json/json_test.go
index b40e000..8256be2 100644
--- a/json/json_test.go
+++ b/json/json_test.go
@@ -240,7 +240,7 @@ var testValues = [...]any{
 		A string         `json:"name"`
 		B string         `json:"-"`
 		C string         `json:",omitempty"`
-		D map[string]any `json:",string"`
+		D map[string]any `json:",string"` //nolint:staticcheck // intentional
 		e string
 	}{A: "Luke", D: map[string]any{"answer": float64(42)}},
 	struct{ point }{point{1, 2}},
@@ -880,12 +880,11 @@ func TestDecodeLines(t *testing.T) {
 		t.Run(test.desc, func(t *testing.T) {
 			d := NewDecoder(test.reader)
 			var count int
-			var err error
 			for {
 				var o obj
-				err = d.Decode(&o)
+				err := d.Decode(&o)
 				if err != nil {
-					if err == io.EOF {
+					if errors.Is(err, io.EOF) {
 						break
 					}
 
@@ -904,10 +903,6 @@ func TestDecodeLines(t *testing.T) {
 				count++
 			}
 
-			if err != nil && err != io.EOF {
-				t.Error(err)
-			}
-
 			if count != test.expectCount {
 				t.Errorf("expected %d objects, got %d", test.expectCount, count)
 			}
diff --git a/json/parse.go b/json/parse.go
index 949e7f3..d0ee221 100644
--- a/json/parse.go
+++ b/json/parse.go
@@ -21,11 +21,6 @@ const (
 	cr = '\r'
 )
 
-const (
-	escape = '\\'
-	quote  = '"'
-)
-
 func internalParseFlags(b []byte) (flags ParseFlags) {
 	// Don't consider surrounding whitespace
 	b = skipSpaces(b)