diff --git a/sjson.go b/sjson.go
index 7f1d358..91e6fc0 100644
--- a/sjson.go
+++ b/sjson.go
@@ -3,9 +3,7 @@ package sjson
 
 import (
 	jsongo "encoding/json"
-	"reflect"
 	"strconv"
-	"unsafe"
 
 	"github.com/tidwall/gjson"
 )
@@ -400,72 +398,6 @@ func isOptimisticPath(path string) bool {
 	return true
 }
 
-func set(jstr, path, raw string,
-	stringify, del, optimistic, inplace bool) ([]byte, error) {
-	if path == "" {
-		return nil, &errorType{"path cannot be empty"}
-	}
-	if !del && optimistic && isOptimisticPath(path) {
-		res := gjson.Get(jstr, path)
-		if res.Exists() && res.Index > 0 {
-			sz := len(jstr) - len(res.Raw) + len(raw)
-			if stringify {
-				sz += 2
-			}
-			if inplace && sz <= len(jstr) {
-				if !stringify || !mustMarshalString(raw) {
-					jsonh := *(*reflect.StringHeader)(unsafe.Pointer(&jstr))
-					jsonbh := reflect.SliceHeader{
-						Data: jsonh.Data, Len: jsonh.Len, Cap: jsonh.Len}
-					jbytes := *(*[]byte)(unsafe.Pointer(&jsonbh))
-					if stringify {
-						jbytes[res.Index] = '"'
-						copy(jbytes[res.Index+1:], []byte(raw))
-						jbytes[res.Index+1+len(raw)] = '"'
-						copy(jbytes[res.Index+1+len(raw)+1:],
-							jbytes[res.Index+len(res.Raw):])
-					} else {
-						copy(jbytes[res.Index:], []byte(raw))
-						copy(jbytes[res.Index+len(raw):],
-							jbytes[res.Index+len(res.Raw):])
-					}
-					return jbytes[:sz], nil
-				}
-				return nil, nil
-			}
-			buf := make([]byte, 0, sz)
-			buf = append(buf, jstr[:res.Index]...)
-			if stringify {
-				buf = appendStringify(buf, raw)
-			} else {
-				buf = append(buf, raw...)
-			}
-			buf = append(buf, jstr[res.Index+len(res.Raw):]...)
-			return buf, nil
-		}
-	}
-	// parse the path, make sure that it does not contain invalid characters
-	// such as '#', '?', '*'
-	paths := make([]pathResult, 0, 4)
-	r, err := parsePath(path)
-	if err != nil {
-		return nil, err
-	}
-	paths = append(paths, r)
-	for r.more {
-		if r, err = parsePath(r.path); err != nil {
-			return nil, err
-		}
-		paths = append(paths, r)
-	}
-
-	njson, err := appendRawPaths(nil, jstr, paths, raw, stringify, del)
-	if err != nil {
-		return nil, err
-	}
-	return njson, nil
-}
-
 // Set sets a json value for the specified path.
 // A path is in dot syntax, such as "name.last" or "age".
 // This function expects that the json is well-formed, and does not validate.
@@ -491,29 +423,6 @@ func Set(json, path string, value interface{}) (string, error) {
 	return SetOptions(json, path, value, nil)
 }
 
-// SetOptions sets a json value for the specified path with options.
-// A path is in dot syntax, such as "name.last" or "age".
-// This function expects that the json is well-formed, and does not validate.
-// Invalid json will not panic, but it may return back unexpected results.
-// An error is returned if the path is not valid.
-func SetOptions(json, path string, value interface{},
-	opts *Options) (string, error) {
-	if opts != nil {
-		if opts.ReplaceInPlace {
-			// it's not safe to replace bytes in-place for strings
-			// copy the Options and set options.ReplaceInPlace to false.
-			nopts := *opts
-			opts = &nopts
-			opts.ReplaceInPlace = false
-		}
-	}
-	jsonh := *(*reflect.StringHeader)(unsafe.Pointer(&json))
-	jsonbh := reflect.SliceHeader{Data: jsonh.Data, Len: jsonh.Len}
-	jsonb := *(*[]byte)(unsafe.Pointer(&jsonbh))
-	res, err := SetBytesOptions(jsonb, path, value, opts)
-	return string(res), err
-}
-
 // SetBytes sets a json value for the specified path.
 // If working with bytes, this method preferred over
 // Set(string(data), path, value)
@@ -521,77 +430,6 @@ func SetBytes(json []byte, path string, value interface{}) ([]byte, error) {
 	return SetBytesOptions(json, path, value, nil)
 }
 
-// SetBytesOptions sets a json value for the specified path with options.
-// If working with bytes, this method preferred over
-// SetOptions(string(data), path, value)
-func SetBytesOptions(json []byte, path string, value interface{},
-	opts *Options) ([]byte, error) {
-	var optimistic, inplace bool
-	if opts != nil {
-		optimistic = opts.Optimistic
-		inplace = opts.ReplaceInPlace
-	}
-	jstr := *(*string)(unsafe.Pointer(&json))
-	var res []byte
-	var err error
-	switch v := value.(type) {
-	default:
-		b, err := jsongo.Marshal(value)
-		if err != nil {
-			return nil, err
-		}
-		raw := *(*string)(unsafe.Pointer(&b))
-		res, err = set(jstr, path, raw, false, false, optimistic, inplace)
-	case dtype:
-		res, err = set(jstr, path, "", false, true, optimistic, inplace)
-	case string:
-		res, err = set(jstr, path, v, true, false, optimistic, inplace)
-	case []byte:
-		raw := *(*string)(unsafe.Pointer(&v))
-		res, err = set(jstr, path, raw, true, false, optimistic, inplace)
-	case bool:
-		if v {
-			res, err = set(jstr, path, "true", false, false, optimistic, inplace)
-		} else {
-			res, err = set(jstr, path, "false", false, false, optimistic, inplace)
-		}
-	case int8:
-		res, err = set(jstr, path, strconv.FormatInt(int64(v), 10),
-			false, false, optimistic, inplace)
-	case int16:
-		res, err = set(jstr, path, strconv.FormatInt(int64(v), 10),
-			false, false, optimistic, inplace)
-	case int32:
-		res, err = set(jstr, path, strconv.FormatInt(int64(v), 10),
-			false, false, optimistic, inplace)
-	case int64:
-		res, err = set(jstr, path, strconv.FormatInt(int64(v), 10),
-			false, false, optimistic, inplace)
-	case uint8:
-		res, err = set(jstr, path, strconv.FormatUint(uint64(v), 10),
-			false, false, optimistic, inplace)
-	case uint16:
-		res, err = set(jstr, path, strconv.FormatUint(uint64(v), 10),
-			false, false, optimistic, inplace)
-	case uint32:
-		res, err = set(jstr, path, strconv.FormatUint(uint64(v), 10),
-			false, false, optimistic, inplace)
-	case uint64:
-		res, err = set(jstr, path, strconv.FormatUint(uint64(v), 10),
-			false, false, optimistic, inplace)
-	case float32:
-		res, err = set(jstr, path, strconv.FormatFloat(float64(v), 'f', -1, 64),
-			false, false, optimistic, inplace)
-	case float64:
-		res, err = set(jstr, path, strconv.FormatFloat(float64(v), 'f', -1, 64),
-			false, false, optimistic, inplace)
-	}
-	if err == errNoChange {
-		return json, nil
-	}
-	return res, err
-}
-
 // SetRaw sets a raw json value for the specified path.
 // This function works the same as Set except that the value is set as a
 // raw block of json. This allows for setting premarshalled json objects.
@@ -621,25 +459,6 @@ func SetRawBytes(json []byte, path string, value []byte) ([]byte, error) {
 	return SetRawBytesOptions(json, path, value, nil)
 }
 
-// SetRawBytesOptions sets a raw json value for the specified path with options.
-// If working with bytes, this method preferred over
-// SetRawOptions(string(data), path, value, opts)
-func SetRawBytesOptions(json []byte, path string, value []byte,
-	opts *Options) ([]byte, error) {
-	jstr := *(*string)(unsafe.Pointer(&json))
-	vstr := *(*string)(unsafe.Pointer(&value))
-	var optimistic, inplace bool
-	if opts != nil {
-		optimistic = opts.Optimistic
-		inplace = opts.ReplaceInPlace
-	}
-	res, err := set(jstr, path, vstr, false, false, optimistic, inplace)
-	if err == errNoChange {
-		return json, nil
-	}
-	return res, err
-}
-
 type dtype struct{}
 
 // Delete deletes a value from json for the specified path.
diff --git a/sjson_gae.go b/sjson_gae.go
new file mode 100644
index 0000000..4b83a17
--- /dev/null
+++ b/sjson_gae.go
@@ -0,0 +1,196 @@
+//+build appengine
+
+package sjson
+
+import (
+	jsongo "encoding/json"
+	"strconv"
+
+	"github.com/tidwall/gjson"
+)
+
+func set(jstr, path, raw string,
+	stringify, del, optimistic, inplace bool) ([]byte, error) {
+	if path == "" {
+		return nil, &errorType{"path cannot be empty"}
+	}
+	if !del && optimistic && isOptimisticPath(path) {
+		res := gjson.Get(jstr, path)
+		if res.Exists() && res.Index > 0 {
+			sz := len(jstr) - len(res.Raw) + len(raw)
+			if stringify {
+				sz += 2
+			}
+			if inplace && sz <= len(jstr) {
+				if !stringify || !mustMarshalString(raw) {
+					// jsonh := *(*reflect.StringHeader)(unsafe.Pointer(&jstr))
+					// jsonbh := reflect.SliceHeader{
+					// 	Data: jsonh.Data, Len: jsonh.Len, Cap: jsonh.Len}
+					// jbytes := *(*[]byte)(unsafe.Pointer(&jsonbh))
+					jbytes := []byte(jstr)
+					if stringify {
+						jbytes[res.Index] = '"'
+						copy(jbytes[res.Index+1:], []byte(raw))
+						jbytes[res.Index+1+len(raw)] = '"'
+						copy(jbytes[res.Index+1+len(raw)+1:],
+							jbytes[res.Index+len(res.Raw):])
+					} else {
+						copy(jbytes[res.Index:], []byte(raw))
+						copy(jbytes[res.Index+len(raw):],
+							jbytes[res.Index+len(res.Raw):])
+					}
+					return jbytes[:sz], nil
+				}
+				return nil, nil
+			}
+			buf := make([]byte, 0, sz)
+			buf = append(buf, jstr[:res.Index]...)
+			if stringify {
+				buf = appendStringify(buf, raw)
+			} else {
+				buf = append(buf, raw...)
+			}
+			buf = append(buf, jstr[res.Index+len(res.Raw):]...)
+			return buf, nil
+		}
+	}
+	// parse the path, make sure that it does not contain invalid characters
+	// such as '#', '?', '*'
+	paths := make([]pathResult, 0, 4)
+	r, err := parsePath(path)
+	if err != nil {
+		return nil, err
+	}
+	paths = append(paths, r)
+	for r.more {
+		if r, err = parsePath(r.path); err != nil {
+			return nil, err
+		}
+		paths = append(paths, r)
+	}
+
+	njson, err := appendRawPaths(nil, jstr, paths, raw, stringify, del)
+	if err != nil {
+		return nil, err
+	}
+	return njson, nil
+}
+
+// SetOptions sets a json value for the specified path with options.
+// A path is in dot syntax, such as "name.last" or "age".
+// This function expects that the json is well-formed, and does not validate.
+// Invalid json will not panic, but it may return back unexpected results.
+// An error is returned if the path is not valid.
+func SetOptions(json, path string, value interface{},
+	opts *Options) (string, error) {
+	if opts != nil {
+		if opts.ReplaceInPlace {
+			// it's not safe to replace bytes in-place for strings
+			// copy the Options and set options.ReplaceInPlace to false.
+			nopts := *opts
+			opts = &nopts
+			opts.ReplaceInPlace = false
+		}
+	}
+	// jsonh := *(*reflect.StringHeader)(unsafe.Pointer(&json))
+	// jsonbh := reflect.SliceHeader{Data: jsonh.Data, Len: jsonh.Len}
+	// jsonb := *(*[]byte)(unsafe.Pointer(&jsonbh))
+	jsonb := []byte(json)
+	res, err := SetBytesOptions(jsonb, path, value, opts)
+	return string(res), err
+}
+
+// SetBytesOptions sets a json value for the specified path with options.
+// If working with bytes, this method preferred over
+// SetOptions(string(data), path, value)
+func SetBytesOptions(json []byte, path string, value interface{},
+	opts *Options) ([]byte, error) {
+	var optimistic, inplace bool
+	if opts != nil {
+		optimistic = opts.Optimistic
+		inplace = opts.ReplaceInPlace
+	}
+	// jstr := *(*string)(unsafe.Pointer(&json))
+	jstr := string(json)
+	var res []byte
+	var err error
+	switch v := value.(type) {
+	default:
+		b, err := jsongo.Marshal(value)
+		if err != nil {
+			return nil, err
+		}
+		// raw := *(*string)(unsafe.Pointer(&b))
+		raw := string(b)
+		res, err = set(jstr, path, raw, false, false, optimistic, inplace)
+	case dtype:
+		res, err = set(jstr, path, "", false, true, optimistic, inplace)
+	case string:
+		res, err = set(jstr, path, v, true, false, optimistic, inplace)
+	case []byte:
+		// raw := *(*string)(unsafe.Pointer(&v))
+		raw := string(v)
+		res, err = set(jstr, path, raw, true, false, optimistic, inplace)
+	case bool:
+		if v {
+			res, err = set(jstr, path, "true", false, false, optimistic, inplace)
+		} else {
+			res, err = set(jstr, path, "false", false, false, optimistic, inplace)
+		}
+	case int8:
+		res, err = set(jstr, path, strconv.FormatInt(int64(v), 10),
+			false, false, optimistic, inplace)
+	case int16:
+		res, err = set(jstr, path, strconv.FormatInt(int64(v), 10),
+			false, false, optimistic, inplace)
+	case int32:
+		res, err = set(jstr, path, strconv.FormatInt(int64(v), 10),
+			false, false, optimistic, inplace)
+	case int64:
+		res, err = set(jstr, path, strconv.FormatInt(int64(v), 10),
+			false, false, optimistic, inplace)
+	case uint8:
+		res, err = set(jstr, path, strconv.FormatUint(uint64(v), 10),
+			false, false, optimistic, inplace)
+	case uint16:
+		res, err = set(jstr, path, strconv.FormatUint(uint64(v), 10),
+			false, false, optimistic, inplace)
+	case uint32:
+		res, err = set(jstr, path, strconv.FormatUint(uint64(v), 10),
+			false, false, optimistic, inplace)
+	case uint64:
+		res, err = set(jstr, path, strconv.FormatUint(uint64(v), 10),
+			false, false, optimistic, inplace)
+	case float32:
+		res, err = set(jstr, path, strconv.FormatFloat(float64(v), 'f', -1, 64),
+			false, false, optimistic, inplace)
+	case float64:
+		res, err = set(jstr, path, strconv.FormatFloat(float64(v), 'f', -1, 64),
+			false, false, optimistic, inplace)
+	}
+	if err == errNoChange {
+		return json, nil
+	}
+	return res, err
+}
+
+// SetRawBytesOptions sets a raw json value for the specified path with options.
+// If working with bytes, this method preferred over
+// SetRawOptions(string(data), path, value, opts)
+func SetRawBytesOptions(json []byte, path string, value []byte,
+	opts *Options) ([]byte, error) {
+	// jstr := *(*string)(unsafe.Pointer(&json))
+	// vstr := *(*string)(unsafe.Pointer(&value))
+	jstr := string(json)
+	vstr := string(value)
+	var optimistic, inplace bool
+	if opts != nil {
+		optimistic = opts.Optimistic
+		inplace = opts.ReplaceInPlace
+	}
+	res, err := set(jstr, path, vstr, false, false, optimistic, inplace)
+	if err == errNoChange {
+		return json, nil
+	}
+	return res, err
+}
diff --git a/sjson_ngae.go b/sjson_ngae.go
new file mode 100644
index 0000000..f3624f4
--- /dev/null
+++ b/sjson_ngae.go
@@ -0,0 +1,191 @@
+//+build !appengine
+
+package sjson
+
+import (
+	jsongo "encoding/json"
+	"reflect"
+	"strconv"
+	"unsafe"
+
+	"github.com/tidwall/gjson"
+)
+
+func set(jstr, path, raw string,
+	stringify, del, optimistic, inplace bool) ([]byte, error) {
+	if path == "" {
+		return nil, &errorType{"path cannot be empty"}
+	}
+	if !del && optimistic && isOptimisticPath(path) {
+		res := gjson.Get(jstr, path)
+		if res.Exists() && res.Index > 0 {
+			sz := len(jstr) - len(res.Raw) + len(raw)
+			if stringify {
+				sz += 2
+			}
+			if inplace && sz <= len(jstr) {
+				if !stringify || !mustMarshalString(raw) {
+					jsonh := *(*reflect.StringHeader)(unsafe.Pointer(&jstr))
+					jsonbh := reflect.SliceHeader{
+						Data: jsonh.Data, Len: jsonh.Len, Cap: jsonh.Len}
+					jbytes := *(*[]byte)(unsafe.Pointer(&jsonbh))
+					if stringify {
+						jbytes[res.Index] = '"'
+						copy(jbytes[res.Index+1:], []byte(raw))
+						jbytes[res.Index+1+len(raw)] = '"'
+						copy(jbytes[res.Index+1+len(raw)+1:],
+							jbytes[res.Index+len(res.Raw):])
+					} else {
+						copy(jbytes[res.Index:], []byte(raw))
+						copy(jbytes[res.Index+len(raw):],
+							jbytes[res.Index+len(res.Raw):])
+					}
+					return jbytes[:sz], nil
+				}
+				return nil, nil
+			}
+			buf := make([]byte, 0, sz)
+			buf = append(buf, jstr[:res.Index]...)
+			if stringify {
+				buf = appendStringify(buf, raw)
+			} else {
+				buf = append(buf, raw...)
+			}
+			buf = append(buf, jstr[res.Index+len(res.Raw):]...)
+			return buf, nil
+		}
+	}
+	// parse the path, make sure that it does not contain invalid characters
+	// such as '#', '?', '*'
+	paths := make([]pathResult, 0, 4)
+	r, err := parsePath(path)
+	if err != nil {
+		return nil, err
+	}
+	paths = append(paths, r)
+	for r.more {
+		if r, err = parsePath(r.path); err != nil {
+			return nil, err
+		}
+		paths = append(paths, r)
+	}
+
+	njson, err := appendRawPaths(nil, jstr, paths, raw, stringify, del)
+	if err != nil {
+		return nil, err
+	}
+	return njson, nil
+}
+
+// SetOptions sets a json value for the specified path with options.
+// A path is in dot syntax, such as "name.last" or "age".
+// This function expects that the json is well-formed, and does not validate.
+// Invalid json will not panic, but it may return back unexpected results.
+// An error is returned if the path is not valid.
+func SetOptions(json, path string, value interface{},
+	opts *Options) (string, error) {
+	if opts != nil {
+		if opts.ReplaceInPlace {
+			// it's not safe to replace bytes in-place for strings
+			// copy the Options and set options.ReplaceInPlace to false.
+			nopts := *opts
+			opts = &nopts
+			opts.ReplaceInPlace = false
+		}
+	}
+	jsonh := *(*reflect.StringHeader)(unsafe.Pointer(&json))
+	jsonbh := reflect.SliceHeader{Data: jsonh.Data, Len: jsonh.Len}
+	jsonb := *(*[]byte)(unsafe.Pointer(&jsonbh))
+	res, err := SetBytesOptions(jsonb, path, value, opts)
+	return string(res), err
+}
+
+// SetBytesOptions sets a json value for the specified path with options.
+// If working with bytes, this method preferred over
+// SetOptions(string(data), path, value)
+func SetBytesOptions(json []byte, path string, value interface{},
+	opts *Options) ([]byte, error) {
+	var optimistic, inplace bool
+	if opts != nil {
+		optimistic = opts.Optimistic
+		inplace = opts.ReplaceInPlace
+	}
+	jstr := *(*string)(unsafe.Pointer(&json))
+	var res []byte
+	var err error
+	switch v := value.(type) {
+	default:
+		b, err := jsongo.Marshal(value)
+		if err != nil {
+			return nil, err
+		}
+		raw := *(*string)(unsafe.Pointer(&b))
+		res, err = set(jstr, path, raw, false, false, optimistic, inplace)
+	case dtype:
+		res, err = set(jstr, path, "", false, true, optimistic, inplace)
+	case string:
+		res, err = set(jstr, path, v, true, false, optimistic, inplace)
+	case []byte:
+		raw := *(*string)(unsafe.Pointer(&v))
+		res, err = set(jstr, path, raw, true, false, optimistic, inplace)
+	case bool:
+		if v {
+			res, err = set(jstr, path, "true", false, false, optimistic, inplace)
+		} else {
+			res, err = set(jstr, path, "false", false, false, optimistic, inplace)
+		}
+	case int8:
+		res, err = set(jstr, path, strconv.FormatInt(int64(v), 10),
+			false, false, optimistic, inplace)
+	case int16:
+		res, err = set(jstr, path, strconv.FormatInt(int64(v), 10),
+			false, false, optimistic, inplace)
+	case int32:
+		res, err = set(jstr, path, strconv.FormatInt(int64(v), 10),
+			false, false, optimistic, inplace)
+	case int64:
+		res, err = set(jstr, path, strconv.FormatInt(int64(v), 10),
+			false, false, optimistic, inplace)
+	case uint8:
+		res, err = set(jstr, path, strconv.FormatUint(uint64(v), 10),
+			false, false, optimistic, inplace)
+	case uint16:
+		res, err = set(jstr, path, strconv.FormatUint(uint64(v), 10),
+			false, false, optimistic, inplace)
+	case uint32:
+		res, err = set(jstr, path, strconv.FormatUint(uint64(v), 10),
+			false, false, optimistic, inplace)
+	case uint64:
+		res, err = set(jstr, path, strconv.FormatUint(uint64(v), 10),
+			false, false, optimistic, inplace)
+	case float32:
+		res, err = set(jstr, path, strconv.FormatFloat(float64(v), 'f', -1, 64),
+			false, false, optimistic, inplace)
+	case float64:
+		res, err = set(jstr, path, strconv.FormatFloat(float64(v), 'f', -1, 64),
+			false, false, optimistic, inplace)
+	}
+	if err == errNoChange {
+		return json, nil
+	}
+	return res, err
+}
+
+// SetRawBytesOptions sets a raw json value for the specified path with options.
+// If working with bytes, this method preferred over
+// SetRawOptions(string(data), path, value, opts)
+func SetRawBytesOptions(json []byte, path string, value []byte,
+	opts *Options) ([]byte, error) {
+	jstr := *(*string)(unsafe.Pointer(&json))
+	vstr := *(*string)(unsafe.Pointer(&value))
+	var optimistic, inplace bool
+	if opts != nil {
+		optimistic = opts.Optimistic
+		inplace = opts.ReplaceInPlace
+	}
+	res, err := set(jstr, path, vstr, false, false, optimistic, inplace)
+	if err == errNoChange {
+		return json, nil
+	}
+	return res, err
+}