diff --git a/app/build.gradle.kts b/app/build.gradle.kts
index 4d8a5fb..8f12cf5 100644
--- a/app/build.gradle.kts
+++ b/app/build.gradle.kts
@@ -189,6 +189,8 @@ composeCompiler {
 dependencies {
 
     implementation(project(mapOf("path" to ":selector")))
+    implementation(project(mapOf("path" to ":json5")))
+
     implementation(libs.androidx.appcompat)
     implementation(libs.androidx.core.ktx)
     implementation(libs.androidx.lifecycle.runtime.ktx)
diff --git a/app/src/main/kotlin/li/songe/gkd/data/RawSubscription.kt b/app/src/main/kotlin/li/songe/gkd/data/RawSubscription.kt
index e8ea2f3..2137289 100644
--- a/app/src/main/kotlin/li/songe/gkd/data/RawSubscription.kt
+++ b/app/src/main/kotlin/li/songe/gkd/data/RawSubscription.kt
@@ -16,8 +16,8 @@ import kotlinx.serialization.json.jsonPrimitive
 import kotlinx.serialization.json.long
 import li.songe.gkd.service.checkSelector
 import li.songe.gkd.util.json
-import li.songe.gkd.util.json5ToJson
 import li.songe.gkd.util.toast
+import li.songe.json5.Json5
 import li.songe.selector.Selector
 import net.objecthunter.exp4j.Expression
 import net.objecthunter.exp4j.ExpressionBuilder
@@ -798,8 +798,9 @@ data class RawSubscription(
         }
 
         fun parse(source: String, json5: Boolean = true): RawSubscription {
-            val text = if (json5) json5ToJson(source) else source
-            val subscription = jsonToSubscriptionRaw(json.parseToJsonElement(text).jsonObject)
+            val element =
+                if (json5) Json5.parseToJson5Element(source) else json.parseToJsonElement(source)
+            val subscription = jsonToSubscriptionRaw(element.jsonObject)
             subscription.categories.findDuplicatedItem { v -> v.key }?.let { v ->
                 error("id=${subscription.id}, duplicated category: key=${v.key}")
             }
@@ -840,9 +841,8 @@ data class RawSubscription(
             return a
         }
 
-        fun parseRawApp(source: String, json5: Boolean = true): RawApp {
-            val text = if (json5) json5ToJson(source) else source
-            return parseApp(json.parseToJsonElement(text).jsonObject)
+        fun parseRawApp(source: String): RawApp {
+            return parseApp(Json5.parseToJson5Element(source).jsonObject)
         }
 
         fun parseGroup(jsonObject: JsonObject): RawAppGroup {
@@ -853,14 +853,12 @@ data class RawSubscription(
             return g
         }
 
-        fun parseRawGroup(source: String, json5: Boolean = true): RawAppGroup {
-            val text = if (json5) json5ToJson(source) else source
-            return parseGroup(json.parseToJsonElement(text).jsonObject)
+        fun parseRawGroup(source: String): RawAppGroup {
+            return parseGroup(Json5.parseToJson5Element(source).jsonObject)
         }
 
-        fun parseRawGlobalGroup(source: String, json5: Boolean = true): RawGlobalGroup {
-            val text = if (json5) json5ToJson(source) else source
-            val g = jsonToGlobalGroups(json.parseToJsonElement(text).jsonObject, 0)
+        fun parseRawGlobalGroup(source: String): RawGlobalGroup {
+            val g = jsonToGlobalGroups(Json5.parseToJson5Element(source).jsonObject, 0)
             g.rules.findDuplicatedItem { v -> v.key }?.let { v ->
                 error("duplicated global rule: key=${v.key}")
             }
diff --git a/app/src/main/kotlin/li/songe/gkd/ui/AppItemPage.kt b/app/src/main/kotlin/li/songe/gkd/ui/AppItemPage.kt
index f970327..87dd14f 100644
--- a/app/src/main/kotlin/li/songe/gkd/ui/AppItemPage.kt
+++ b/app/src/main/kotlin/li/songe/gkd/ui/AppItemPage.kt
@@ -75,15 +75,15 @@ import li.songe.gkd.util.LocalMainViewModel
 import li.songe.gkd.util.LocalNavController
 import li.songe.gkd.util.ProfileTransitions
 import li.songe.gkd.util.appInfoCacheFlow
-import li.songe.gkd.util.encodeToJson5String
+import li.songe.json5.encodeToJson5String
 import li.songe.gkd.util.getGroupRawEnable
 import li.songe.gkd.util.json
-import li.songe.gkd.util.json5ToJson
 import li.songe.gkd.util.launchAsFn
 import li.songe.gkd.util.launchTry
 import li.songe.gkd.util.throttle
 import li.songe.gkd.util.toast
 import li.songe.gkd.util.updateSubscription
+import li.songe.json5.Json5
 
 @RootNavGraph
 @Destination(style = ProfileTransitions::class)
@@ -285,7 +285,7 @@ fun AppItemPage(
                                     },
                                 )
                             }
-                            if (editable && subsItem != null && subsRaw != null) {
+                            if (editable && subsRaw != null) {
                                 DropdownMenuItem(
                                     text = {
                                         Text(text = "删除", color = MaterialTheme.colorScheme.error)
@@ -435,8 +435,9 @@ fun AppItemPage(
                         setEditGroupRaw(null)
                         return@launchAsFn
                     }
+
                     val element = try {
-                        json.parseToJsonElement(json5ToJson(source)).jsonObject
+                        Json5.parseToJson5Element(source).jsonObject
                     } catch (e: Exception) {
                         LogUtils.d(e)
                         error("非法JSON:${e.message}")
diff --git a/app/src/main/kotlin/li/songe/gkd/ui/GlobalRulePage.kt b/app/src/main/kotlin/li/songe/gkd/ui/GlobalRulePage.kt
index 54ad05e..396e89a 100644
--- a/app/src/main/kotlin/li/songe/gkd/ui/GlobalRulePage.kt
+++ b/app/src/main/kotlin/li/songe/gkd/ui/GlobalRulePage.kt
@@ -72,7 +72,7 @@ import li.songe.gkd.ui.style.itemPadding
 import li.songe.gkd.util.LocalMainViewModel
 import li.songe.gkd.util.LocalNavController
 import li.songe.gkd.util.ProfileTransitions
-import li.songe.gkd.util.encodeToJson5String
+import li.songe.json5.encodeToJson5String
 import li.songe.gkd.util.json
 import li.songe.gkd.util.launchAsFn
 import li.songe.gkd.util.launchTry
@@ -260,7 +260,7 @@ fun GlobalRulePage(subsItemId: Long, focusGroupKey: Int? = null) {
                                                 error = true,
                                             )
                                             updateSubscription(
-                                                rawSubs!!.copy(
+                                                rawSubs.copy(
                                                     globalGroups = rawSubs.globalGroups.filter { g -> g.key != group.key }
                                                 )
                                             )
diff --git a/app/src/main/kotlin/li/songe/gkd/ui/SubsPage.kt b/app/src/main/kotlin/li/songe/gkd/ui/SubsPage.kt
index bd027aa..3a2d3b0 100644
--- a/app/src/main/kotlin/li/songe/gkd/ui/SubsPage.kt
+++ b/app/src/main/kotlin/li/songe/gkd/ui/SubsPage.kt
@@ -65,7 +65,7 @@ import li.songe.gkd.util.LocalNavController
 import li.songe.gkd.util.ProfileTransitions
 import li.songe.gkd.util.SortTypeOption
 import li.songe.gkd.util.appInfoCacheFlow
-import li.songe.gkd.util.encodeToJson5String
+import li.songe.json5.encodeToJson5String
 import li.songe.gkd.util.json
 import li.songe.gkd.util.launchAsFn
 import li.songe.gkd.util.launchTry
diff --git a/app/src/main/kotlin/li/songe/gkd/ui/component/SubsAppCard.kt b/app/src/main/kotlin/li/songe/gkd/ui/component/SubsAppCard.kt
index 8693128..39fd91f 100644
--- a/app/src/main/kotlin/li/songe/gkd/ui/component/SubsAppCard.kt
+++ b/app/src/main/kotlin/li/songe/gkd/ui/component/SubsAppCard.kt
@@ -41,7 +41,7 @@ import li.songe.gkd.data.AppInfo
 import li.songe.gkd.data.RawSubscription
 import li.songe.gkd.data.SubsConfig
 import li.songe.gkd.ui.style.appItemPadding
-import li.songe.gkd.util.encodeToJson5String
+import li.songe.json5.encodeToJson5String
 import li.songe.gkd.util.json
 import li.songe.gkd.util.toast
 
diff --git a/app/src/main/kotlin/li/songe/gkd/util/Json5.kt b/app/src/main/kotlin/li/songe/gkd/util/Json5.kt
deleted file mode 100644
index 32802c6..0000000
--- a/app/src/main/kotlin/li/songe/gkd/util/Json5.kt
+++ /dev/null
@@ -1,99 +0,0 @@
-package li.songe.gkd.util
-
-import blue.endless.jankson.Jankson
-import kotlinx.serialization.json.Json
-import kotlinx.serialization.json.JsonArray
-import kotlinx.serialization.json.JsonElement
-import kotlinx.serialization.json.JsonObject
-import kotlinx.serialization.json.JsonPrimitive
-import kotlinx.serialization.serializer
-
-private val json5IdentifierReg = Regex("[a-zA-Z_][a-zA-Z0-9_]*")
-
-/**
- * https://spec.json5.org/#strings
- */
-private fun escapeString(value: String): String {
-    val wrapChar = '\''
-    val sb = StringBuilder()
-    sb.append(wrapChar)
-    value.forEach { c ->
-        val escapeChar = when (c) {
-            wrapChar -> wrapChar
-            '\n' -> 'n'
-            '\r' -> 'r'
-            '\t' -> 't'
-            '\b' -> 'b'
-            '\\' -> '\\'
-            else -> null
-        }
-        if (escapeChar != null) {
-            sb.append("\\" + escapeChar)
-        } else {
-            when (c.code) {
-                in 0..0xf -> {
-                    sb.append("\\x0" + c.code.toString(16))
-                }
-
-                in 0..0x1f -> {
-                    sb.append("\\x" + c.code.toString(16))
-                }
-
-                else -> {
-                    sb.append(c)
-                }
-            }
-        }
-    }
-    sb.append(wrapChar)
-    return sb.toString()
-}
-
-fun convertJsonElementToJson5(element: JsonElement, indent: Int = 2): String {
-    val spaces = "\u0020".repeat(indent)
-    return when (element) {
-        is JsonPrimitive -> {
-            val content = element.content
-            if (element.isString) {
-                escapeString(content)
-            } else {
-                content
-            }
-        }
-
-        is JsonObject -> {
-            if (element.isEmpty()) {
-                "{}"
-            } else {
-                val entries = element.entries.joinToString(",\n") { (key, value) ->
-                    // If key is a valid identifier, no quotes are needed
-                    if (key.matches(json5IdentifierReg)) {
-                        "$key: ${convertJsonElementToJson5(value, indent)}"
-                    } else {
-                        "${escapeString(key)}: ${convertJsonElementToJson5(value, indent)}"
-                    }
-                }.lineSequence().map { l -> spaces + l }.joinToString("\n")
-                "{\n$entries\n}"
-            }
-        }
-
-        is JsonArray -> {
-            if (element.isEmpty()) {
-                "[]"
-            } else {
-                val elements =
-                    element.joinToString(",\n") { convertJsonElementToJson5(it, indent) }
-                        .lineSequence().map { l -> spaces + l }.joinToString("\n")
-                "[\n$elements\n]"
-            }
-        }
-    }
-}
-
-inline fun <reified T> Json.encodeToJson5String(value: T): String {
-    return convertJsonElementToJson5(encodeToJsonElement(serializersModule.serializer(), value))
-}
-
-fun json5ToJson(source: String): String {
-    return Jankson.builder().build().load(source).toJson()
-}
\ No newline at end of file
diff --git a/app/src/main/kotlin/li/songe/gkd/util/SubsState.kt b/app/src/main/kotlin/li/songe/gkd/util/SubsState.kt
index 0eb6810..efdc4cf 100644
--- a/app/src/main/kotlin/li/songe/gkd/util/SubsState.kt
+++ b/app/src/main/kotlin/li/songe/gkd/util/SubsState.kt
@@ -32,6 +32,7 @@ import li.songe.gkd.data.SubsConfig
 import li.songe.gkd.data.SubsItem
 import li.songe.gkd.data.SubsVersion
 import li.songe.gkd.db.DbSet
+import li.songe.json5.decodeFromJson5String
 import java.net.URI
 
 val subsItemsFlow by lazy {
@@ -121,7 +122,7 @@ fun getGroupRawEnable(
         enable
     } else {
         null
-    } ?: group.enable != false
+    } ?: group.enable ?: true
 }
 
 data class RuleSummary(
@@ -190,7 +191,7 @@ val ruleSummaryFlow by lazy {
                 mutableMapOf<RawSubscription.RawGlobalGroup, List<GlobalRule>>()
             rawSubs.globalGroups.filter { g ->
                 (subGlobalSubsConfigs.find { c -> c.groupKey == g.key }?.enable
-                        ?: g.enable != false) && g.valid
+                        ?: g.enable ?: true) && g.valid
             }.forEach { groupRaw ->
                 val config = subGlobalSubsConfigs.find { c -> c.groupKey == groupRaw.key }
                 val g = ResolvedGlobalGroup(
@@ -347,10 +348,8 @@ private suspend fun updateSubs(subsEntry: SubsEntry): RawSubscription? {
     val checkUpdateUrl = subsEntry.checkUpdateUrl
     if (checkUpdateUrl != null && subsRaw != null) {
         try {
-            val subsVersion = json.decodeFromString<SubsVersion>(
-                json5ToJson(
-                    client.get(checkUpdateUrl).bodyAsText()
-                )
+            val subsVersion = json.decodeFromJson5String<SubsVersion>(
+                client.get(checkUpdateUrl).bodyAsText()
             )
             LogUtils.d(
                 "快速检测更新:id=${subsRaw.id},version=${subsRaw.version}",
diff --git a/build.gradle.kts b/build.gradle.kts
index 61106fa..4628a9c 100644
--- a/build.gradle.kts
+++ b/build.gradle.kts
@@ -29,6 +29,7 @@ plugins {
     alias(libs.plugins.kotlin.compose) apply false
 
     alias(libs.plugins.rikka.refine) apply false
+    alias(libs.plugins.jetbrains.kotlin.jvm) apply false
 }
 
 // can not work with Kotlin Multiplatform
diff --git a/gradle/libs.versions.toml b/gradle/libs.versions.toml
index 3e1130d..f5178be 100644
--- a/gradle/libs.versions.toml
+++ b/gradle/libs.versions.toml
@@ -1,7 +1,7 @@
 [versions]
 kotlin = "2.0.10"
 ksp = "2.0.10-1.0.24"
-android = "8.5.1"
+android = "8.5.2"
 compose = "1.6.8"
 rikka = "4.4.0"
 room = "2.6.1"
@@ -10,12 +10,14 @@ ktor = "2.3.12"
 hilt = "2.52"
 destinations = "1.10.2"
 coil = "2.7.0"
+jetbrainsKotlinJvm = "2.0.10"
 
 [libraries]
 android_gradle = { module = "com.android.tools.build:gradle", version.ref = "android" }
 kotlin_gradle_plugin = { module = "org.jetbrains.kotlin:kotlin-gradle-plugin", version.ref = "kotlin" }
 kotlin_serialization = { module = "org.jetbrains.kotlin:kotlin-serialization", version.ref = "kotlin" }
 kotlin_stdlib_common = { module = "org.jetbrains.kotlin:kotlin-stdlib-common", version.ref = "kotlin" }
+kotlin_test = { module = "org.jetbrains.kotlin:kotlin-test", version.ref = "kotlin" }
 compose_ui = { module = "androidx.compose.ui:ui", version.ref = "compose" }
 compose_preview = { module = "androidx.compose.ui:ui-tooling-preview", version.ref = "compose" }
 compose_tooling = { module = "androidx.compose.ui:ui-tooling", version.ref = "compose" }
@@ -80,3 +82,4 @@ rikka_refine = { id = "dev.rikka.tools.refine", version.ref = "rikka" }
 google_ksp = { id = "com.google.devtools.ksp", version.ref = "ksp" }
 google_hilt = { id = "com.google.dagger.hilt.android", version.ref = "hilt" }
 androidx_room = { id = "androidx.room", version.ref = "room" }
+jetbrains-kotlin-jvm = { id = "org.jetbrains.kotlin.jvm", version.ref = "jetbrainsKotlinJvm" }
diff --git a/json5/.gitignore b/json5/.gitignore
new file mode 100644
index 0000000..42afabf
--- /dev/null
+++ b/json5/.gitignore
@@ -0,0 +1 @@
+/build
\ No newline at end of file
diff --git a/json5/build.gradle.kts b/json5/build.gradle.kts
new file mode 100644
index 0000000..5b8922e
--- /dev/null
+++ b/json5/build.gradle.kts
@@ -0,0 +1,22 @@
+plugins {
+    alias(libs.plugins.kotlin.multiplatform)
+    alias(libs.plugins.kotlin.serialization)
+}
+
+kotlin {
+    jvm()
+
+    sourceSets {
+        val commonMain by getting {
+            dependencies {
+                api(libs.kotlinx.serialization.json)
+            }
+        }
+        val commonTest by getting {
+            dependencies {
+                implementation(libs.kotlin.test)
+                implementation(libs.kotlinx.serialization.json)
+            }
+        }
+    }
+}
diff --git a/json5/src/commonMain/kotlin/li/songe/json5/Json5.kt b/json5/src/commonMain/kotlin/li/songe/json5/Json5.kt
new file mode 100644
index 0000000..fd6bd60
--- /dev/null
+++ b/json5/src/commonMain/kotlin/li/songe/json5/Json5.kt
@@ -0,0 +1,64 @@
+package li.songe.json5
+
+import kotlinx.serialization.json.JsonArray
+import kotlinx.serialization.json.JsonElement
+import kotlinx.serialization.json.JsonObject
+import kotlinx.serialization.json.JsonPrimitive
+
+object Json5 {
+    fun parseToJson5Element(string: String): JsonElement {
+        return Json5Decoder(string).read()
+    }
+
+    fun encodeToString(element: JsonElement, indent: Int = 2) = encodeToString(element, indent, 0)
+
+    private fun encodeToString(element: JsonElement, indent: Int = 2, depth: Int = 0): String {
+        val lineSeparator = if (indent == 0) "" else "\n"
+        val keySeparator = if (indent == 0) ":" else ": "
+        val prefixSpaces = if (indent == 0) "" else " ".repeat(indent * (depth + 1))
+        val closingSpaces = if (indent == 0) "" else " ".repeat(indent * depth)
+
+        return when (element) {
+            is JsonPrimitive -> {
+                if (element.isString) {
+                    stringifyString(element.content)
+                } else {
+                    element.content
+                }
+            }
+
+            is JsonObject -> {
+                if (element.isEmpty()) {
+                    "{}"
+                } else {
+                    element.entries.joinToString(",$lineSeparator") { (key, value) ->
+                        "${prefixSpaces}${stringifyKey(key)}${keySeparator}${
+                            encodeToString(
+                                value,
+                                indent,
+                                depth + 1
+                            )
+                        }"
+                    }.let {
+                        "{$lineSeparator$it$lineSeparator$closingSpaces}"
+                    }
+                }
+            }
+
+            is JsonArray -> {
+                if (element.isEmpty()) {
+                    "[]"
+                } else {
+                    element.joinToString(",$lineSeparator") {
+                        "${prefixSpaces}${encodeToString(it, indent, depth + 1)}"
+                    }.let {
+                        "[$lineSeparator$it$lineSeparator$closingSpaces]"
+                    }
+                }
+            }
+        }
+    }
+
+}
+
+
diff --git a/json5/src/commonMain/kotlin/li/songe/json5/Json5Decoder.kt b/json5/src/commonMain/kotlin/li/songe/json5/Json5Decoder.kt
new file mode 100644
index 0000000..6010712
--- /dev/null
+++ b/json5/src/commonMain/kotlin/li/songe/json5/Json5Decoder.kt
@@ -0,0 +1,539 @@
+package li.songe.json5
+
+import kotlinx.serialization.json.*
+import java.lang.StringBuilder
+import kotlin.collections.set
+import kotlin.let
+import kotlin.ranges.contains
+import kotlin.text.endsWith
+import kotlin.text.getOrNull
+import kotlin.text.substring
+import kotlin.text.toDouble
+import kotlin.text.toInt
+import kotlin.text.toLong
+import kotlin.text.trimEnd
+
+// https://spec.json5.org/
+internal class Json5Decoder(private val input: CharSequence) {
+    private var i = 0
+    private val char: Char?
+        get() = input.getOrNull(i)
+    private val end: Boolean
+        get() = i >= input.length
+
+    private fun stop(): Nothing {
+        if (end) {
+            error("Unexpected Char: EOF")
+        }
+        error("Unexpected Char: $char at index $i")
+    }
+
+    fun read(): JsonElement {
+        val root = i == 0
+        readUseless()
+        val element = when (char) {
+            '{' -> readObject()
+            '[' -> readArray()
+            '"', '\'' -> JsonPrimitive(readString())
+            in '0'..'9', '-', '+', '.', 'N', 'I' -> JsonPrimitive(readNumber())
+            't' -> { // true
+                i++
+                next('r')
+                next('u')
+                next('e')
+                JsonPrimitive(true)
+            }
+
+            'f' -> { // false
+                i++
+                next('a')
+                next('l')
+                next('s')
+                next('e')
+                JsonPrimitive(false)
+            }
+
+            'n' -> { // null
+                i++
+                next('u')
+                next('l')
+                next('l')
+                JsonNull
+            }
+
+            else -> stop()
+        }
+        if (root) {
+            readUseless()
+            if (!end) {
+                stop()
+            }
+        }
+        return element
+    }
+
+    private fun next(c: Char) {
+        if (c == char) {
+            i++
+            return
+        }
+        stop()
+    }
+
+    private fun readObject(): JsonObject {
+        i++
+        readUseless()
+        if (char == '}') {
+            i++
+            return JsonObject(emptyMap())
+        }
+        val map = mutableMapOf<String, JsonElement>()
+        while (true) {
+            readUseless()
+            val key = readObjectKey()
+            readUseless()
+            next(':')
+            readUseless()
+            val value = read()
+            map[key] = value
+            readUseless()
+            if (char == '}') {
+                i++
+                break
+            } else if (char == ',') {
+                i++
+                readUseless()
+                if (char == '}') {
+                    i++
+                    break
+                }
+            } else {
+                stop()
+            }
+        }
+        return JsonObject(map)
+    }
+
+    private fun readObjectKey(): String {
+        val c = char
+        if (c == '\'' || c == '"') {
+            return readString()
+        }
+        val sb = StringBuilder()
+        if (c == '\\') {
+            i++
+            next('u')
+            repeat(4) {
+                if (!isHexDigit(char)) {
+                    stop()
+                }
+                i++
+            }
+            val n = input.substring(i - 4, i).toInt(16).toChar()
+            if (!isIdStartChar(n)) {
+                stop()
+            }
+            sb.append(n)
+        } else if (!isIdStartChar(c)) {
+            stop()
+        } else {
+            sb.append(c)
+        }
+        i++
+        while (!end) {
+            if (char == '\\') {
+                i++
+                next('u')
+                repeat(4) {
+                    if (!isHexDigit(char)) {
+                        stop()
+                    }
+                    i++
+                }
+                val n = input.substring(i - 4, i).toInt(16).toChar()
+                if (!isIdContinueChar(n)) {
+                    stop()
+                }
+                sb.append(n)
+            } else if (isIdContinueChar(char)) {
+                sb.append(char)
+                i++
+            } else {
+                break
+            }
+        }
+        return sb.toString()
+    }
+
+    private fun readArray(): JsonArray {
+        i++
+        readUseless()
+        if (char == ']') {
+            i++
+            return JsonArray(emptyList())
+        }
+        val list = mutableListOf<JsonElement>()
+        while (true) {
+            readUseless()
+            list.add(read())
+            readUseless()
+            if (char == ']') {
+                i++
+                break
+            } else if (char == ',') {
+                i++
+                readUseless()
+                if (char == ']') {
+                    i++
+                    break
+                }
+            } else {
+                stop()
+            }
+        }
+        return JsonArray(list)
+    }
+
+    private fun readString(): String {
+        val wrapChar = char!!
+        i++
+        val sb = StringBuilder()
+        while (true) {
+            when (char) {
+                null -> stop()
+                wrapChar -> {
+                    i++
+                    break
+                }
+
+                '\\' -> {
+                    i++
+                    when (char) {
+                        null -> stop()
+                        wrapChar -> {
+                            sb.append(wrapChar)
+                            i++
+                        }
+
+                        'x' -> {
+                            i++
+                            repeat(2) {
+                                if (!isHexDigit(char)) {
+                                    stop()
+                                }
+                                i++
+                            }
+                            val hex = input.substring(i - 2, i)
+                            sb.append(hex.toInt(16).toChar())
+                        }
+
+                        'u' -> {
+                            i++
+                            repeat(4) {
+                                if (!isHexDigit(char)) {
+                                    stop()
+                                }
+                                i++
+                            }
+                            val hex = input.substring(i - 4, i)
+                            sb.append(hex.toInt(16).toChar())
+                        }
+
+                        '\'' -> {
+                            sb.append('\'')
+                            i++
+                        }
+
+                        '\"' -> {
+                            sb.append('\"')
+                            i++
+                        }
+
+                        '\\' -> {
+                            sb.append('\\')
+                            i++
+                        }
+
+                        'b' -> {
+                            sb.append('\b')
+                            i++
+                        }
+
+                        'f' -> {
+                            sb.append('\u000C')
+                            i++
+                        }
+
+                        'n' -> {
+                            sb.append('\n')
+                            i++
+                        }
+
+                        'r' -> {
+                            sb.append('\r')
+                            i++
+                        }
+
+                        't' -> {
+                            sb.append('\t')
+                            i++
+                        }
+
+                        'v' -> {
+                            sb.append('\u000B')
+                            i++
+                        }
+
+                        '0' -> {
+                            sb.append('\u0000')
+                            i++
+                            if (isDigit(char)) {
+                                stop()
+                            }
+                        }
+
+                        // multiline string
+                        '\u000D' -> {// \r
+                            i++
+                            if (char == '\u000A') {// \n
+                                i++
+                            }
+                        }
+
+                        // multiline string
+                        '\u000A', '\u2028', '\u2029' -> {
+                            i++
+                        }
+
+                        in '1'..'9' -> stop()
+
+                        else -> {
+                            sb.append(char)
+                        }
+                    }
+                }
+
+                else -> {
+                    sb.append(char)
+                    i++
+                }
+            }
+        }
+        return sb.toString()
+    }
+
+    private fun readNumber(signal: Boolean = false): Number {
+        return when (char) {
+            '-' -> {
+                if (!signal) {
+                    i++
+                    val n = readNumber(true)
+                    if (n is Double) {
+                        return -n
+                    }
+                    if (n is Long) {
+                        return -n
+                    }
+                    if (n is Int) {
+                        return -n
+                    }
+                    stop()
+                } else {
+                    stop()
+                }
+            }
+
+            '+' -> {
+                if (!signal) {
+                    i++
+                    return readNumber(true)
+                } else {
+                    stop()
+                }
+            }
+
+            'N' -> {// NaN
+                i++
+                next('a')
+                next('N')
+                Double.NaN
+            }
+
+            'I' -> {// Infinity
+                i++
+                next('n')
+                next('f')
+                next('i')
+                next('n')
+                next('i')
+                next('t')
+                next('y')
+                Double.POSITIVE_INFINITY
+            }
+
+            '.' -> {
+                var start = i
+                i++
+                readInteger()
+                val numPart = input.substring(start, i).trimEnd('0').let {
+                    if (it == ".") { // .0 -> 0
+                        "0"
+                    } else {
+                        it
+                    }
+                }
+                if (numPart == "0") {
+                    0L
+                } else {
+                    if (isPowerStartChar(char)) {
+                        start = i + 1
+                        readNumberPower()
+                        val power = input.substring(start, i)
+                        (numPart + power).toDouble()
+                    } else {
+                        input.substring(start, i).toDouble()
+                    }
+                }
+            }
+
+            in '0'..'9' -> {
+                var start = i
+                var hasHex = false
+                if (char == '0') { // 0x11
+                    i++
+                    if (isDigit(char)) {// not allow 00 01
+                        stop()
+                    } else if (isHexStartChar(char)) {
+                        i++
+                        hasHex = true
+                    }
+                }
+                if (hasHex) {
+                    if (!isHexDigit(char)) {
+                        stop()
+                    }
+                    i++
+                    while (!end && isHexDigit(char)) {
+                        i++
+                    }
+                    input.substring(start + 2, i).toLong(16)
+                } else {
+                    var hasPoint = false // 1.2
+                    while (!end) {
+                        if (char == '.') {
+                            if (!hasPoint) {
+                                hasPoint = true
+                            } else {
+                                stop()
+                            }
+                        } else if (!isDigit(char)) {
+                            break
+                        }
+                        i++
+                    }
+                    val hasEndPoint = hasPoint && input[i - 1] == '.' // kotlin not support 1.
+                    val numPart = if (hasEndPoint) {
+                        hasPoint = false
+                        input.substring(start, i - 1) // 1. -> 1
+                    } else {
+                        if (hasPoint) {
+                            input.substring(start, i).trimEnd('0').let { // 1.10 -> 1.1, 1.0 -> 1.
+                                if (it.endsWith('.')) { // 1. -> 1
+                                    hasPoint = false
+                                    it.substring(0, it.length - 1)
+                                } else {
+                                    it
+                                }
+                            }
+                        } else {
+                            input.substring(start, i)
+                        }
+                    }
+                    if (isPowerStartChar(char)) {
+                        start = i
+                        readNumberPower()
+                        val power = input.substring(start, i)
+                        (numPart + power).toDouble()
+                    } else {
+                        if (hasPoint) {
+                            numPart.toDouble()
+                        } else {
+                            numPart.run { toLongOrNull() ?: toDouble() }
+                        }
+                    }
+                }
+            }
+
+            else -> stop()
+        }
+    }
+
+    private fun readInteger() {
+        val start = i
+        while (isDigit(char)) {
+            i++
+        }
+        if (start == i) {
+            stop()
+        }
+    }
+
+    private fun readNumberPower() {
+        i++
+        if (char == '-' || char == '+') {
+            i++
+        }
+        readInteger()
+    }
+
+    private fun readUseless() {
+        while (true) {
+            val oldIndex = i
+            readCommentOrWhitespace()
+            if (oldIndex == i) {
+                return
+            }
+        }
+    }
+
+    private fun readCommentOrWhitespace() {
+        when {
+            char == '/' -> {
+                i++
+                when (char) {
+                    '/' -> {
+                        i++
+                        while (!isNewLine(char) && !end) {
+                            i++
+                        }
+                    }
+
+                    '*' -> {
+                        i++
+                        while (true) {
+                            when (char) {
+                                null -> stop()
+                                '*' -> {
+                                    if (input.getOrNull(i + 1) == '/') {
+                                        i += 2
+                                        break
+                                    }
+                                }
+                            }
+                            i++
+                        }
+                    }
+
+                    else -> stop()
+                }
+            }
+
+            isWhiteSpace(char) -> {
+                i++
+                while (isWhiteSpace(char)) {
+                    i++
+                }
+            }
+        }
+    }
+}
diff --git a/json5/src/commonMain/kotlin/li/songe/json5/JsonExt.kt b/json5/src/commonMain/kotlin/li/songe/json5/JsonExt.kt
new file mode 100644
index 0000000..ee4aa87
--- /dev/null
+++ b/json5/src/commonMain/kotlin/li/songe/json5/JsonExt.kt
@@ -0,0 +1,15 @@
+package li.songe.json5
+
+import kotlinx.serialization.json.Json
+import kotlinx.serialization.json.decodeFromJsonElement
+import kotlinx.serialization.serializer
+
+inline fun <reified T> Json.encodeToJson5String(value: T): String {
+    return Json5.encodeToString(
+        encodeToJsonElement(serializersModule.serializer(), value),
+    )
+}
+
+inline fun <reified T> Json.decodeFromJson5String(value: String): T {
+    return decodeFromJsonElement<T>(Json5.parseToJson5Element(value))
+}
diff --git a/json5/src/commonMain/kotlin/li/songe/json5/Util.kt b/json5/src/commonMain/kotlin/li/songe/json5/Util.kt
new file mode 100644
index 0000000..4037a0a
--- /dev/null
+++ b/json5/src/commonMain/kotlin/li/songe/json5/Util.kt
@@ -0,0 +1,149 @@
+package li.songe.json5
+
+import kotlin.text.category
+
+private val unicodeLetterCategories = hashSetOf(
+    CharCategory.UPPERCASE_LETTER,
+    CharCategory.LOWERCASE_LETTER,
+    CharCategory.TITLECASE_LETTER,
+    CharCategory.MODIFIER_LETTER,
+    CharCategory.OTHER_LETTER,
+    CharCategory.LETTER_NUMBER,
+)
+
+private val unicodeIdCategories = hashSetOf(
+    CharCategory.NON_SPACING_MARK,
+    CharCategory.COMBINING_SPACING_MARK,
+    CharCategory.DECIMAL_DIGIT_NUMBER,
+    CharCategory.CONNECTOR_PUNCTUATION,
+)
+
+internal fun isIdStartChar(c: Char?): Boolean {
+    c ?: return false
+    return c.category in unicodeLetterCategories || c == '_' || c == '$'
+}
+
+internal fun isIdContinueChar(c: Char?): Boolean {
+    c ?: return false
+    return isIdStartChar(c) || c.category in unicodeIdCategories || c == '\u200C' || c == '\u200D'
+}
+
+internal fun isDigit(c: Char?): Boolean {
+    c ?: return false
+    return c in '0'..'9'
+}
+
+internal fun isHexDigit(c: Char?): Boolean {
+    c ?: return false
+    return (c in '0'..'9') || (c in 'A'..'F') || (c in 'a'..'f')
+}
+
+internal fun isPowerStartChar(c: Char?): Boolean {
+    c ?: return false
+    return c == 'e' || c == 'E'
+}
+
+internal fun isHexStartChar(c: Char?): Boolean {
+    c ?: return false
+    return c == 'x' || c == 'X'
+}
+
+internal fun isWhiteSpace(c: Char?): Boolean {
+    c ?: return false
+    return when (c) {
+        '\u0009' -> true
+        in '\u000A'..'\u000D' -> true
+        '\u0020' -> true
+        '\u00A0' -> true
+        '\u2028' -> true
+        '\u2029' -> true
+        '\uFEFF' -> true
+
+        '\u1680' -> true
+        in '\u2000'..'\u200A' -> true
+        '\u202F' -> true
+        '\u205F' -> true
+        '\u3000' -> true
+        else -> false
+    }
+}
+
+internal fun isNewLine(c: Char?): Boolean {
+    c ?: return false
+    return when (c) {
+        '\u000A' -> true
+        '\u000D' -> true
+        '\u2028' -> true
+        '\u2029' -> true
+        else -> false
+    }
+}
+
+private val escapeReplacements = hashMapOf(
+    '\\' to "\\\\",
+    '\b' to "\\b",
+    '\u000C' to "\\f",
+    '\n' to "\\n",
+    '\r' to "\\r",
+    '\t' to "\\t",
+    '\u000B' to "\\v",
+    '\u0000' to "\\0",
+    '\u2028' to "\\u2028",
+    '\u2029' to "\\u2029",
+)
+
+internal fun stringifyString(value: String, singleQuote: Boolean = true): String {
+    // https://github.com/json5/json5/blob/main/lib/stringify.js
+    val wrapChar = if (singleQuote) '\'' else '"'
+    val sb = StringBuilder()
+    sb.append(wrapChar)
+    value.forEachIndexed { i, c ->
+        when {
+            c == wrapChar -> {
+                sb.append("\\$wrapChar")
+            }
+
+            c == '\u0000' -> {
+                if (isDigit(value.getOrNull(i + 1))) {
+                    // "\u00002" -> \x002
+                    sb.append("\\x00")
+                } else {
+                    sb.append("\\0")
+                }
+            }
+
+            c in escapeReplacements.keys -> {
+                sb.append(escapeReplacements[c])
+            }
+
+            c.code in 0..0xf -> {
+                sb.append("\\x0" + c.code.toString(16))
+            }
+
+            c.code in 0..0x1f -> {
+                sb.append("\\x" + c.code.toString(16))
+            }
+
+            else -> {
+                sb.append(c)
+            }
+        }
+    }
+    sb.append(wrapChar)
+    return sb.toString()
+}
+
+internal fun stringifyKey(key: String, singleQuote: Boolean = true): String {
+    if (key.isEmpty()) {
+        return stringifyString(key, singleQuote)
+    }
+    if (!isIdStartChar(key[0])) {
+        return stringifyString(key, singleQuote)
+    }
+    for (c in key) {
+        if (!isIdContinueChar(c)) {
+            return stringifyString(key, singleQuote)
+        }
+    }
+    return key
+}
diff --git a/json5/src/commonTest/kotlin/li/songe/json5/Json5Test.kt b/json5/src/commonTest/kotlin/li/songe/json5/Json5Test.kt
new file mode 100644
index 0000000..61d12c4
--- /dev/null
+++ b/json5/src/commonTest/kotlin/li/songe/json5/Json5Test.kt
@@ -0,0 +1,21 @@
+package li.songe.json5
+
+import kotlin.test.Test
+
+class Json5Test {
+
+    @Test
+    fun parse() {
+        // https://github.com/json5/json5/blob/main/test/parse.js
+        val element = Json5.parseToJson5Element("[1,2,3,'\\x002\\n']/*23*///1")
+        println("element: $element")
+    }
+
+    @Test
+    fun format() {
+        val element = Json5.parseToJson5Element("{'a-1':1,b:{c:['d',{f:233}]}}")
+        println("element: $element")
+        val formatted = Json5.encodeToString(element, 2)
+        println("formatted:\n$formatted")
+    }
+}
diff --git a/selector/build.gradle.kts b/selector/build.gradle.kts
index 540669c..645370b 100644
--- a/selector/build.gradle.kts
+++ b/selector/build.gradle.kts
@@ -7,12 +7,7 @@ plugins {
 }
 
 kotlin {
-    jvm {
-        @OptIn(ExperimentalKotlinGradlePluginApi::class)
-        compilerOptions {
-            jvmTarget.set(JvmTarget.JVM_17)
-        }
-    }
+    jvm()
 //    https://kotlinlang.org/docs/js-to-kotlin-interop.html#kotlin-types-in-javascript
     js(IR) {
         binaries.executable()
diff --git a/settings.gradle.kts b/settings.gradle.kts
index 986b215..e49f1f7 100644
--- a/settings.gradle.kts
+++ b/settings.gradle.kts
@@ -23,3 +23,4 @@ dependencyResolutionManagement {
     }
 }
 
+include(":json5")