Fix

packages/server/src/rpc/RPCPlaygroundRoute.ts

@@ -0,0 +1,23 @@
+import { Effect, Layer } from "effect"
+import { expressHandler } from "trpc-playground/handlers/express"
+import { ExpressApp } from "../express/ExpressApp"
+import { RPCRouter } from "./RPCRouter"
+import { rpcPlaygroundRoot, rpcRoot } from "./config"
+
+
+export module RPCPlaygroundRoute {
+    export const Live = Layer.empty
+
+    export const Dev = Layer.effectDiscard(Effect.gen(function*() {
+        const app                = yield* ExpressApp
+        const playgroundEndpoint = yield* rpcPlaygroundRoot
+
+        const handler = expressHandler({
+            trpcApiEndpoint: yield* rpcRoot,
+            playgroundEndpoint,
+            router: yield* RPCRouter,
+        })
+
+        app.use(playgroundEndpoint, yield* Effect.promise(() => handler))
+    }))
+}