diff --git a/packages/effect-fc/src/ErrorObserver.ts b/packages/effect-fc/src/ErrorObserver.ts
index 30f5424..75930af 100644
--- a/packages/effect-fc/src/ErrorObserver.ts
+++ b/packages/effect-fc/src/ErrorObserver.ts
@@ -1,20 +1,20 @@
 import { type Cause, Context, Effect, Exit, Layer, Option, Pipeable, Predicate, PubSub, type Queue, type Scope, Supervisor } from "effect"
 
 
-export const TypeId: unique symbol = Symbol.for("@effect-fc/ErrorObserver/ErrorObserver")
-export type TypeId = typeof TypeId
+export const ErrorObserverTypeId: unique symbol = Symbol.for("@effect-fc/ErrorObserver/ErrorObserver")
+export type ErrorObserverTypeId = typeof ErrorObserverTypeId
 
 export interface ErrorObserver<in out E = never> extends Pipeable.Pipeable {
-    readonly [TypeId]: TypeId
+    readonly [ErrorObserverTypeId]: ErrorObserverTypeId
     handle<A, E, R>(effect: Effect.Effect<A, E, R>): Effect.Effect<A, E, R>
     readonly subscribe: Effect.Effect<Queue.Dequeue<Cause.Cause<E>>, never, Scope.Scope>
 }
 
 export const ErrorObserver = <E = never>(): Context.Tag<ErrorObserver, ErrorObserver<E>> => Context.GenericTag("@effect-fc/ErrorObserver/ErrorObserver")
 
-class ErrorObserverImpl<in out E = never>
+export class ErrorObserverImpl<in out E = never>
 extends Pipeable.Class() implements ErrorObserver<E> {
-    readonly [TypeId]: TypeId = TypeId
+    readonly [ErrorObserverTypeId]: ErrorObserverTypeId = ErrorObserverTypeId
     readonly subscribe: Effect.Effect<Queue.Dequeue<Cause.Cause<E>>, never, Scope.Scope>
 
     constructor(
@@ -29,7 +29,7 @@ extends Pipeable.Class() implements ErrorObserver<E> {
     }
 }
 
-class ErrorObserverSupervisorImpl extends Supervisor.AbstractSupervisor<void> {
+export class ErrorObserverSupervisorImpl extends Supervisor.AbstractSupervisor<void> {
     readonly value = Effect.void
     constructor(readonly pubsub: PubSub.PubSub<Cause.Cause<never>>) {
         super()
@@ -43,7 +43,7 @@ class ErrorObserverSupervisorImpl extends Supervisor.AbstractSupervisor<void> {
 }
 
 
-export const isErrorObserver = (u: unknown): u is ErrorObserver<unknown> => Predicate.hasProperty(u, TypeId)
+export const isErrorObserver = (u: unknown): u is ErrorObserver<unknown> => Predicate.hasProperty(u, ErrorObserverTypeId)
 
 export const layer: Layer.Layer<ErrorObserver> = Layer.unwrapEffect(Effect.map(
     PubSub.unbounded<Cause.Cause<never>>(),