diff --git a/README.md b/README.md
index e35cdc8..0487752 100644
--- a/README.md
+++ b/README.md
@@ -24,8 +24,8 @@ The generator can be used with any tool that can perform system calls to a comma
 See example under [example/generate.scala](./example/generate.scala).
 
 ```scala
-//> using scala 3.7.3
-//> using dep dev.rolang::gcp-codegen::0.0.8
+//> using scala 3.7.4
+//> using dep dev.rolang::gcp-codegen::0.0.12
 
 import gcp.codegen.*, java.nio.file.*, GeneratorConfig.*
 
@@ -55,13 +55,41 @@ See output in `example/out`.
 
 | Configuration       | Description | Options | Default |
 | ------------------- | ---------------- | ------- | --- |
-| -specs             | Can be `stdin` or a path to the JSON file. | | |
-| -out-dir           | Ouput directory | | |
-| -out-pkg           | Output package |  | |
-| -http-source       | Generated http source. | [Sttp4](https://sttp.softwaremill.com/en/stable) | |
-| -json-codec        | Generated JSON codec | [Jsoniter](https://github.com/plokhotnyuk/jsoniter-scala), [ZioJson](https://zio.dev/zio-json)  | |
-| -array-type        | Collection type for JSON arrays | `List`, `Vector`, `Array`, `ZioChunk` | `List` |
-| -include-resources | Optional resource filter. | | |
+| -specs              | Can be `stdin` or a path to the JSON file. | | |
+| -out-dir            | Output directory | | |
+| -out-pkg            | Output package |  | |
+| -http-source        | Generated http source. | [Sttp4](https://sttp.softwaremill.com/en/stable) | |
+| -json-codec         | Generated JSON codec | [Jsoniter](https://github.com/plokhotnyuk/jsoniter-scala), [ZioJson](https://zio.dev/zio-json)  | |
+| -jsoniter-json-type | In case of Jsoniter a fully qualified name of the custom type that can represent a raw Json value | |
+| -array-type         | Collection type for JSON arrays | `List`, `Vector`, `Array`, `ZioChunk` | `List` |
+| -include-resources  | Optional resource filter. | | |
+
+##### Jsoniter Json type and codec example
+Jsoniter doesn't ship with a type that can represent raw Json values to be used for mapping of `any` / `object` types,  
+but it provides methods to read / write raw values as bytes (related [issue](https://github.com/plokhotnyuk/jsoniter-scala/issues/1257)).  
+Given that we can create a custom type with a codec which can look for example like [that](modules/example-jsoniter-json/shared/src/main/scala/json.scala):
+```scala
+package example.jsoniter
+import com.github.plokhotnyuk.jsoniter_scala.core.*
+
+opaque type Json = Array[Byte]
+object Json:
+  def writeToJson[T: JsonValueCodec](v: T): Json = writeToArray[T](v)
+
+  given codec: JsonValueCodec[Json] = new JsonValueCodec[Json]:
+    override def decodeValue(in: JsonReader, default: Json): Json = in.readRawValAsBytes()
+    override def encodeValue(x: Json, out: JsonWriter): Unit = out.writeRawVal(x)
+    override val nullValue: Json = Array[Byte](0)
+
+  extension (v: Json)
+    def readAsUnsafe[T: JsonValueCodec]: T = readFromArray(v)
+    def readAs[T: JsonValueCodec]: Either[Throwable, T] =
+      try Right(readFromArray(v))
+      catch case t: Throwable => Left(t)
+```
+Then pass it as argument to the code generator like `-jsoniter-json-type=_root_.example.jsoniter.Json`.  
+Since this type and codec can be shared across generated clients it has to be provided (at least for now)
+instead of being generated for each client to avoid duplicated / redundant code.  
 
 ##### Examples:
 
@@ -79,7 +107,7 @@ curl 'https://pubsub.googleapis.com/$discovery/rest?version=v1' > pubsub_v1.json
   -specs=./pubsub_v1.json \
   -out-pkg=gcp.pubsub.v1 \
   -http-source=sttp4 \
-  -json-codec=jsoniter \
+  -json-codec=ziojson \
   -include-resources='projects.*,!projects.snapshots' # optional filters
 ```
 
diff --git a/build.sbt b/build.sbt
index e14bfa5..04541c6 100644
--- a/build.sbt
+++ b/build.sbt
@@ -46,7 +46,7 @@ val zioVersion = "2.1.23"
 
 val zioJsonVersion = "0.8.0"
 
-val jsoniterVersion = "2.38.6"
+val jsoniterVersion = "2.38.8"
 
 val munitVersion = "1.2.1"
 
@@ -58,6 +58,8 @@ lazy val root = (project in file("."))
   .aggregate(
     core.native,
     core.jvm,
+    exampleJsoniterJson.native,
+    exampleJsoniterJson.jvm,
     cli
   )
   .aggregate(testProjects.componentProjects.map(p => LocalProject(p.id)) *)
@@ -65,6 +67,7 @@ lazy val root = (project in file("."))
 
 // for supporting code inspection / testing of generated code via test_gen.sh script
 lazy val testLocal = (project in file("test-local"))
+  .dependsOn(exampleJsoniterJson.jvm)
   .settings(
     libraryDependencies ++= Seq(
       "com.softwaremill.sttp.client4" %% "core" % sttpClient4Version,
@@ -101,6 +104,20 @@ lazy val cli = project
     nativeConfig := nativeConfig.value.withMultithreading(false)
   )
 
+lazy val exampleJsoniterJson = crossProject(JVMPlatform, NativePlatform)
+  .in(file("modules/example-jsoniter-json"))
+  .settings(noPublish)
+  .settings(
+    name := "example-jsoniter-json",
+    moduleName := "example-jsoniter-json"
+  )
+  .settings(
+    libraryDependencies ++= Seq(
+      "com.github.plokhotnyuk.jsoniter-scala" %% "jsoniter-scala-core" % jsoniterVersion,
+      "com.github.plokhotnyuk.jsoniter-scala" %% "jsoniter-scala-macros" % jsoniterVersion % "compile-internal"
+    )
+  )
+
 def dependencyByConfig(httpSource: String, jsonCodec: String, arrayType: String): Seq[ModuleID] = {
   (httpSource match {
     case "Sttp4" => Seq("com.softwaremill.sttp.client4" %% "core" % sttpClient4Version)
@@ -136,7 +153,7 @@ lazy val testProjects: CompositeProject = new CompositeProject {
       arrayType <- Seq("ZioChunk", "List")
       id = s"test-$apiName-$apiVersion-${httpSource}-${jsonCodec}-${arrayType}".toLowerCase()
     } yield {
-      Project
+      val p = Project
         .apply(
           id = id,
           base = file("modules") / id
@@ -155,6 +172,12 @@ lazy val testProjects: CompositeProject = new CompositeProject {
             "com.github.plokhotnyuk.jsoniter-scala" %% "jsoniter-scala-macros" % jsoniterVersion % Test
           ) ++ dependencyByConfig(httpSource = httpSource, jsonCodec = jsonCodec, arrayType = arrayType)
         )
+
+      if (jsonCodec == "Jsoniter") {
+        p.dependsOn(exampleJsoniterJson.componentProjects.map(p => ClasspathDependency(p, p.configuration)) *)
+      } else {
+        p
+      }
     }
 }
 
@@ -235,7 +258,8 @@ def codegenTask(
       s"-out-pkg=$basePkgName",
       s"-http-source=$httpSource",
       s"-json-codec=$jsonCodec",
-      s"-array-type=$arrayType"
+      s"-array-type=$arrayType",
+      s"-jsoniter-json-type=_root_.example.jsoniter.Json"
     ).mkString(" ") ! ProcessLogger(l => logger.info(l), e => errs += e)) match {
       case 0 => ()
       case c => throw new InterruptedException(s"Failure on code generation: ${errs.mkString("\n")}")
diff --git a/example/generate.scala b/example/generate.scala
index a139e8a..d808485 100644
--- a/example/generate.scala
+++ b/example/generate.scala
@@ -1,5 +1,5 @@
-//> using scala 3.7.3
-//> using dep dev.rolang::gcp-codegen::0.0.8
+//> using scala 3.7.4
+//> using dep dev.rolang::gcp-codegen::0.0.12
 
 import gcp.codegen.*, java.nio.file.*, GeneratorConfig.*
 
@@ -10,7 +10,7 @@ import gcp.codegen.*, java.nio.file.*, GeneratorConfig.*
       outDir = Path.of("out"),
       outPkg = "example.pubsub.v1",
       httpSource = HttpSource.Sttp4,
-      jsonCodec = JsonCodec.Jsoniter,
+      jsonCodec = JsonCodec.ZioJson,
       arrayType = ArrayType.List,
       preprocess = specs => specs
     )
diff --git a/modules/cli/src/main/scala/cli.scala b/modules/cli/src/main/scala/cli.scala
index 3544105..5723b76 100644
--- a/modules/cli/src/main/scala/cli.scala
+++ b/modules/cli/src/main/scala/cli.scala
@@ -31,10 +31,10 @@ import scala.concurrent.duration.*
 
 private def argsToTask(args: Seq[String]): Either[String, Task] =
   val argsMap = args.toList
-    .flatMap(_.split('=').map(_.trim().toLowerCase()))
+    .flatMap(_.split('=').map(_.trim()))
     .sliding(2, 2)
     .collect { case a :: b :: _ =>
-      a -> b
+      a.toLowerCase() -> b
     }
     .toMap
 
@@ -57,10 +57,17 @@ private def argsToTask(args: Seq[String]): Either[String, Task] =
       .get("-http-source")
       .flatMap(v => HttpSource.values.find(_.toString().equalsIgnoreCase(v)))
       .toRight("Missing or invalid -http-source")
-    jsonCodec <- argsMap
-      .get("-json-codec")
-      .flatMap(v => JsonCodec.values.find(_.toString().equalsIgnoreCase(v)))
-      .toRight("Missing or invalid -json-codec")
+    jsonCodec <- (
+      argsMap
+        .get("-json-codec")
+        .map(_.toLowerCase()),
+      argsMap.get("-jsoniter-json-type")
+    ) match {
+      case (Some("ziojson"), _)               => Right(JsonCodec.ZioJson)
+      case (Some("jsoniter"), Some(jsonType)) => Right(JsonCodec.Jsoniter(jsonType))
+      case (Some("jsoniter"), None)           => Left("Missing -jsoniter-json-type")
+      case _                                  => Left("Missing or invalid -json-codec")
+    }
     arrayType <- argsMap.get("-array-type") match
       case None    => Right(ArrayType.List)
       case Some(v) => ArrayType.values.find(_.toString().equalsIgnoreCase(v)).toRight(s"Invalid array-type $v")
diff --git a/modules/core/shared/src/main/scala/codegen.scala b/modules/core/shared/src/main/scala/codegen.scala
index 960e8f9..bf76f1c 100644
--- a/modules/core/shared/src/main/scala/codegen.scala
+++ b/modules/core/shared/src/main/scala/codegen.scala
@@ -30,7 +30,8 @@ object GeneratorConfig:
     case Sttp4
 
   enum JsonCodec:
-    case ZioJson, Jsoniter
+    case ZioJson
+    case Jsoniter(jsonTypeRef: String)
 
   enum ArrayType {
     case List, Vector, Array, ZioChunk
@@ -159,15 +160,15 @@ def generateBySpec(
                     "import sttp.model.*\nimport sttp.client4.*, sttp.client4.ResponseException.{DeserializationException, UnexpectedStatusCode}"
                 },
                 config.jsonCodec match {
-                  case JsonCodec.ZioJson  => "import zio.json.*"
-                  case JsonCodec.Jsoniter => "import com.github.plokhotnyuk.jsoniter_scala.core.*"
+                  case JsonCodec.ZioJson     => "import zio.json.*"
+                  case _: JsonCodec.Jsoniter => "import com.github.plokhotnyuk.jsoniter_scala.core.*"
                 },
                 s"val resourceRequest: PartialRequest[Either[String, String]] = basicRequest.headers(Header.contentType(MediaType.ApplicationJson))",
                 "",
                 s"export ${config.outPkg}.QueryParameters",
                 "",
                 (config.httpSource, config.jsonCodec) match
-                  case (HttpSource.Sttp4, JsonCodec.Jsoniter) =>
+                  case (HttpSource.Sttp4, _: JsonCodec.Jsoniter) =>
                     """|def asJson[T : JsonValueCodec]: ResponseAs[Either[ResponseException[String], T]] =
                        |  asByteArrayAlways.mapWithMetadata((bytes, metadata) =>
                        |    if metadata.isSuccess then
@@ -221,23 +222,13 @@ def generateBySpec(
             },
           // generate schemas with properties
           for {
-            (commonCodecs, hasExtraCodecs) <- Future {
-              commonSchemaCodecs(
-                schemas = specs.schemas.filter(_._2.properties.nonEmpty),
-                pkg = schemasPkg,
-                objName = commonCodecsObj,
-                jsonCodec = config.jsonCodec,
-                hasProps = p => specs.hasProps(p),
-                arrType = config.arrayType
-              ) match
-                case None                            => (Nil, false)
-                case Some((content, hasExtraCodecs)) =>
-                  Files.writeString(commonCodecsPath, content)
-                  (List(commonCodecsPath.toFile()), hasExtraCodecs)
-            }
             schemas <- Future
               .traverse(specs.schemas) { (schemaPath, schema) =>
                 Future {
+                  val jsonType = config.jsonCodec match
+                    case JsonCodec.ZioJson               => "zio.json.ast.Json"
+                    case JsonCodec.Jsoniter(jsonTypeRef) => jsonTypeRef
+
                   val code =
                     (if schema.properties.nonEmpty then
                        schemasCode(
@@ -245,16 +236,14 @@ def generateBySpec(
                          pkg = schemasPkg,
                          jsonCodec = config.jsonCodec,
                          hasProps = p => specs.hasProps(p),
-                         arrType = config.arrayType,
-                         commonCodecsPkg =
-                           if commonCodecs.nonEmpty && hasExtraCodecs then Some(commonCodecsPkg) else None
+                         arrType = config.arrayType
                        )
                      else
                        // create a type alias for objects without properties
                        val comment = toComment(schema.description)
                        s"""|package $schemasPkg
                            |
-                           |${comment}type ${schema.id.scalaName} = Option[""]""".stripMargin
+                           |${comment}type ${schema.id.scalaName} = Option[$jsonType]""".stripMargin
                     )
 
                   val path = schemasPath / s"${schemaPath.scalaName}.scala"
@@ -262,7 +251,7 @@ def generateBySpec(
                   path.toFile()
                 }
               }
-          } yield commonCodecs ::: schemas.toList
+          } yield schemas.toList
         )
       )
       .map(_.flatten)
@@ -415,8 +404,7 @@ def schemasCode(
     pkg: String,
     jsonCodec: JsonCodec,
     hasProps: SchemaPath => Boolean,
-    arrType: ArrayType,
-    commonCodecsPkg: Option[String]
+    arrType: ArrayType
 ): String = {
   def enums =
     schema.properties.collect:
@@ -426,26 +414,26 @@ def schemasCode(
   def `def toJsonString`(objName: String) = jsonCodec match
     case JsonCodec.ZioJson =>
       s"def toJsonString: String = $objName.jsonCodec.encodeJson(this, None).toString()"
-    case JsonCodec.Jsoniter =>
+    case _: JsonCodec.Jsoniter =>
       s"def toJsonString: String = writeToString(this)"
 
   def jsonDecoder(objName: String) =
     List(
       s"object $objName {",
-      // Jsoniter doesn't support derivation from Scala 3 union types
-      if jsonCodec == JsonCodec.Jsoniter then
-        enums
-          .map((k, e) =>
-            s"  enum ${toScalaTypeName(k)} {\n${e.values.map(v => s"${toComment(Some(v.enumDescription), "    ")}    case ${toScalaName(v.value)}").mkString("\n  ")}\n  }\n"
-          )
-          .mkString("\n")
-      else "",
       jsonCodec match
         case JsonCodec.ZioJson =>
           s"  given jsonCodec: JsonCodec[$objName] = JsonCodec.derived[$objName]"
-        case JsonCodec.Jsoniter =>
-          s"""|  given jsonCodec: JsonValueCodec[$objName] = 
-              |    JsonCodecMaker.make(CodecMakerConfig.withAllowRecursiveTypes(true).withDiscriminatorFieldName(None))""".stripMargin,
+        case _: JsonCodec.Jsoniter =>
+          // Jsoniter doesn't support derivation from Scala 3 union types
+          enums
+            .map((k, e) =>
+              s"  enum ${toScalaTypeName(k)} {\n${e.values.map(v => s"${toComment(Some(v.enumDescription), "    ")}    case ${toScalaName(v.value)}").mkString("\n  ")}\n  }\n"
+            )
+            .mkString("\n")
+            .appendedAll(
+              s"""|  given jsonCodec: JsonValueCodec[$objName] = 
+              |    JsonCodecMaker.make(CodecMakerConfig.withAllowRecursiveTypes(true).withDiscriminatorFieldName(None))""".stripMargin
+            ),
       "}"
     ).mkString("\n")
 
@@ -473,115 +461,15 @@ def schemasCode(
     s"package $pkg",
     "",
     jsonCodec match {
-      case JsonCodec.ZioJson  => "import zio.json.*"
-      case JsonCodec.Jsoniter =>
+      case JsonCodec.ZioJson     => "import zio.json.*"
+      case _: JsonCodec.Jsoniter =>
         """|import com.github.plokhotnyuk.jsoniter_scala.core.*
            |import com.github.plokhotnyuk.jsoniter_scala.macros.*""".stripMargin
     },
-    commonCodecsPkg match
-      case Some(codecsPkg) => s"import $codecsPkg.given"
-      case _               => "",
     toSchemaClass(schema)
   ).mkString("\n")
 }
 
-def commonSchemaCodecs(
-    schemas: Map[SchemaPath, Schema],
-    pkg: String,
-    objName: String,
-    jsonCodec: JsonCodec,
-    hasProps: SchemaPath => Boolean,
-    arrType: ArrayType
-): Option[(String, Boolean)] = {
-  (jsonCodec match
-    case JsonCodec.ZioJson  => Nil
-    case JsonCodec.Jsoniter =>
-      List(
-        s"""|package $pkg
-            |
-            |import com.github.plokhotnyuk.jsoniter_scala.core.*
-            |import com.github.plokhotnyuk.jsoniter_scala.macros.*
-            |
-            |opaque type Json = Array[Byte]
-            |
-            |object Json {
-            |
-            |  given codec: JsonValueCodec[Json] = new JsonValueCodec[Json] {
-            |    override def decodeValue(in: JsonReader, default: Json): Json = in.readRawValAsBytes()
-            |
-            |    override def encodeValue(x: Json, out: JsonWriter): Unit = out.writeRawVal(x)
-            |
-            |    override val nullValue: Json = new Array[Byte](0)
-            |  }
-            |
-            |  extension (v: Json) 
-            |    def readAsUnsafe[T: JsonValueCodec]: T = readFromArray(v)
-            |    def readAs[T: JsonValueCodec]: Either[Throwable, T] =
-            |      try
-            |        Right(readFromArray(v))
-            |      catch
-            |        case t: Throwable => Left(t)
-            |}""".stripMargin -> false
-      )
-  ).appendedAll((jsonCodec, arrType) match
-    case (JsonCodec.Jsoniter, ArrayType.ZioChunk) =>
-      schemas.toList
-        .flatMap((sk, sv) =>
-          sv.sortedProperties(hasProps)
-            .collect { case (k, Property(_, SchemaType.Array(typ, _), _)) =>
-              val enumType =
-                if jsonCodec == JsonCodec.ZioJson then SchemaType.EnumType.Literal
-                else SchemaType.EnumType.Nominal(s"${sk.lastOption.getOrElse("")}.${toScalaTypeName(k)}")
-              typ.scalaType(arrType, jsonCodec, enumType)
-            }
-        )
-        .distinct match
-        case Nil   => Nil
-        case props =>
-          List(
-            List(
-              "",
-              s"object $objName {",
-              "",
-              // to ensure codec for Chunk[Json] is added since it may not be present in props
-              """|  given JsonChunkCodec: JsonValueCodec[zio.Chunk[Json]] = new JsonValueCodec[zio.Chunk[Json]] {
-                 |    val arrCodec: JsonValueCodec[Array[Json]] = JsonCodecMaker.make
-                 |  
-                 |    override val nullValue: zio.Chunk[Json] = zio.Chunk.empty
-                 |  
-                 |    override def decodeValue(in: JsonReader, default: zio.Chunk[Json]): zio.Chunk[Json] =
-                 |      zio.Chunk.fromArray(arrCodec.decodeValue(in, default.toArray))
-                 |  
-                 |    override def encodeValue(x: zio.Chunk[Json], out: JsonWriter): Unit =
-                 |      arrCodec.encodeValue(x.toArray, out)
-                 |  }""".stripMargin,
-              "",
-              props
-                .filterNot(_ == "Json") // to void duplicate codec for Chunk[Json]
-                .map { t =>
-                  val prefix = "  given " + toScalaName(t + "ChunkCodec")
-                  s"""|${prefix}: JsonValueCodec[zio.Chunk[$t]] = new JsonValueCodec[zio.Chunk[$t]] {
-                          |    val arrCodec: JsonValueCodec[Array[$t]] = JsonCodecMaker.make
-                          |
-                          |    override val nullValue: zio.Chunk[$t] = zio.Chunk.empty
-                          |
-                          |    override def decodeValue(in: JsonReader, default: zio.Chunk[$t]): zio.Chunk[$t] =
-                          |      zio.Chunk.fromArray(arrCodec.decodeValue(in, default.toArray))
-                          |
-                          |    override def encodeValue(x: zio.Chunk[$t], out: JsonWriter): Unit =
-                          |      arrCodec.encodeValue(x.toArray, out)
-                          |}""".stripMargin
-                }
-                .mkString("\n\n"),
-              "}"
-            ).mkString("\n") -> true
-          )
-    case _ => Nil) match
-    case Nil    => None
-    case codecs => Some((codecs.map(_._1).mkString("\n"), codecs.exists(_._2)))
-
-}
-
 case class FlatPath(path: String, params: List[String])
 
 case class MediaUploadProtocol(multipart: Boolean, path: String) derives Reader
@@ -793,8 +681,8 @@ enum SchemaType(val optional: Boolean):
     case _: Object               =>
       toType(
         jsonCodec match
-          case JsonCodec.ZioJson  => "zio.json.ast.Json.Obj"
-          case JsonCodec.Jsoniter => "Json" // assuming the codecs package is imported
+          case JsonCodec.ZioJson           => "zio.json.ast.Json.Obj"
+          case JsonCodec.Jsoniter(jsonRef) => jsonRef
       )
     case Enum(_, values, _) =>
       enumType match
@@ -803,8 +691,8 @@ enum SchemaType(val optional: Boolean):
     case _ =>
       toType(
         jsonCodec match
-          case JsonCodec.ZioJson  => "zio.json.ast.Json"
-          case JsonCodec.Jsoniter => "Json" // assuming the codecs package is imported
+          case JsonCodec.ZioJson           => "zio.json.ast.Json"
+          case JsonCodec.Jsoniter(jsonRef) => jsonRef
       )
 
 object SchemaType:
diff --git a/modules/example-jsoniter-json/shared/src/main/scala/json.scala b/modules/example-jsoniter-json/shared/src/main/scala/json.scala
new file mode 100644
index 0000000..28f0c70
--- /dev/null
+++ b/modules/example-jsoniter-json/shared/src/main/scala/json.scala
@@ -0,0 +1,18 @@
+package example.jsoniter
+
+import com.github.plokhotnyuk.jsoniter_scala.core.*
+
+opaque type Json = Array[Byte]
+object Json:
+  def writeToJson[T: JsonValueCodec](v: T): Json = writeToArray[T](v)
+
+  given codec: JsonValueCodec[Json] = new JsonValueCodec[Json]:
+    override def decodeValue(in: JsonReader, default: Json): Json = in.readRawValAsBytes()
+    override def encodeValue(x: Json, out: JsonWriter): Unit = out.writeRawVal(x)
+    override val nullValue: Json = Array[Byte](0)
+
+  extension (v: Json)
+    def readAsUnsafe[T: JsonValueCodec]: T = readFromArray(v)
+    def readAs[T: JsonValueCodec]: Either[Throwable, T] =
+      try Right(readFromArray(v))
+      catch case t: Throwable => Left(t)
diff --git a/test_gen.sh b/test_gen.sh
index f53a24b..89ec322 100755
--- a/test_gen.sh
+++ b/test_gen.sh
@@ -8,7 +8,7 @@ spec=aiplatform
 version=v1
 json_codec=jsoniter
 http_source=sttp4
-array_type=list
+array_type=ziochunk
 out_dir=test-local/src/main/scala/test-$spec-$version/$http_source/$spec/$json_codec
 rm -rf $out_dir && mkdir -p $out_dir
 
@@ -19,4 +19,5 @@ scala modules/cli/src/main/scala/cli.scala -- \
     -out-pkg=gcp.${spec}.${version}.${http_source}.${json_codec}.$array_type \
     -http-source=$http_source \
     -json-codec=$json_codec \
+    -jsoniter-json-type=_root_.custom.jsoniter.Json \
     -array-type=$array_type
\ No newline at end of file