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kotlinlang

Doesn't solve your problem but I think you can just call `proceed()` - equivalent to `proceedWith(subject)`

Not sure about HttpClientExtensionsKt though - is that yours? Might need to hand over to someone more knowledgeable :disappointed:

Are you using yandex-checkout-android-sdk? It's the only thing that seems to come up with a search for "HttpClientExtensions Kt"

I have that function too
```
suspend fun HttpClient.forward(call: ApplicationCall) {
    val exchange = this.call(call.request.uri) {
		method = call.request.httpMethod
        headers.appendAll(getValidHeaders(call.request.headers))
        body = object : OutgoingContent.WriteChannelContent() {
			override val contentType = call.request.contentType()

			override suspend fun writeTo(channel: ByteWriteChannel) {
				call.request.receiveChannel().copyAndClose(channel)
			}
		}
	}
}
```

Hmmm and that calls into this.call(uri, someLambda)
And somewhere we end up with some generated class (`clientFeatures.HttpClientExtensionsKt$forward$exchange$1$1`) as the argument for HttpClient.execute further on in the pipeline which fails.
```
suspend fun execute(builder: HttpRequestBuilder): HttpClientCall =
        requestPipeline.execute(builder, builder.body) as HttpClientCall```

I'm afraid I'm not really coroutine nor generated class names savvy enough, plus I finish soon :wink: Sorry bud, hope someone else can help

Next time, consider posting the stacktrace as a reply