diff --git a/ChangeLog.md b/ChangeLog.md
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -1,5 +1,9 @@
 # Changelog for extensible-effects-concurrent
 
+## 0.16.1
+
+- Export `ObserverRegistry` constructors for custom event registration handling
+
 ## 0.16.0
 
 API Stabilization and cleanup release with major API changes.
diff --git a/README.md b/README.md
--- a/README.md
+++ b/README.md
@@ -41,9 +41,6 @@
     firstExample
     lift (threadDelay 100000) -- ... async logging
   )
-    -- The SchedulerProxy paremeter contains the effects of a specific scheduler
-    -- implementation.
-
 
 newtype WhoAreYou = WhoAreYou ProcessId deriving (Typeable, NFData, Show)
 
diff --git a/examples/example-4/Main.hs b/examples/example-4/Main.hs
--- a/examples/example-4/Main.hs
+++ b/examples/example-4/Main.hs
@@ -14,9 +14,6 @@
     firstExample
     lift (threadDelay 100000) -- ... async logging
   )
-    -- The SchedulerProxy paremeter contains the effects of a specific scheduler
-    -- implementation.
-
 
 newtype WhoAreYou = WhoAreYou ProcessId deriving (Typeable, NFData, Show)
 
diff --git a/extensible-effects-concurrent.cabal b/extensible-effects-concurrent.cabal
--- a/extensible-effects-concurrent.cabal
+++ b/extensible-effects-concurrent.cabal
@@ -1,5 +1,5 @@
 name:           extensible-effects-concurrent
-version:        0.16.0
+version:        0.16.1
 description:    Please see the README on GitHub at <https://github.com/sheyll/extensible-effects-concurrent#readme>
 synopsis:       Message passing concurrency as extensible-effect
 homepage:       https://github.com/sheyll/extensible-effects-concurrent#readme
diff --git a/src/Control/Eff/Concurrent.hs b/src/Control/Eff/Concurrent.hs
--- a/src/Control/Eff/Concurrent.hs
+++ b/src/Control/Eff/Concurrent.hs
@@ -17,9 +17,6 @@
     -- ** /Server/ Functions for Providing APIs
     module Control.Eff.Concurrent.Api.Server
   ,
-    -- ** /Server/ Functions for Providing APIs (new experimental)
-    module Control.Eff.Concurrent.Api.Server
-  ,
     -- ** Encapsulate 'Api's 'Cast's as well as 'Call's and their 'Reply's
     module Control.Eff.Concurrent.Api.Request
   ,
@@ -189,6 +186,11 @@
                                                 )
 import           Control.Eff.Concurrent.Api.Observer
                                                 ( Observer(..)
+                                                , Api
+                                                  ( RegisterObserver
+                                                  , ForgetObserver
+                                                  , Observed
+                                                  )
                                                 , registerObserver
                                                 , forgetObserver
                                                 , handleObservations
diff --git a/src/Control/Eff/Concurrent/Api/Observer.hs b/src/Control/Eff/Concurrent/Api/Observer.hs
--- a/src/Control/Eff/Concurrent/Api/Observer.hs
+++ b/src/Control/Eff/Concurrent/Api/Observer.hs
@@ -6,6 +6,7 @@
 -- @since 0.16.0
 module Control.Eff.Concurrent.Api.Observer
   ( Observer(..)
+  , Api(RegisterObserver, ForgetObserver, Observed)
   , registerObserver
   , forgetObserver
   , handleObservations
@@ -101,6 +102,9 @@
 --
 -- @since 0.16.0
 data instance Api (Observer o) r where
+  -- | This message denotes that the given value was 'observed'.
+  --
+  -- @since 0.16.1
   Observed :: o -> Api (Observer o) 'Asynchronous
 
 -- | Based on the 'Api' instance for 'Observer' this simplified writing
@@ -148,7 +152,14 @@
 --
 -- @since 0.16.0
 data instance Api (ObserverRegistry o) r where
+  -- | This message denotes that the given 'Observer' should receive observations until 'ForgetObserver' is
+  --   received.
+  --
+  -- @since 0.16.1
   RegisterObserver :: Observer o -> Api (ObserverRegistry o) 'Asynchronous
+  -- | This message denotes that the given 'Observer' should not receive observations anymore.
+  --
+  -- @since 0.16.1
   ForgetObserver :: Observer o -> Api (ObserverRegistry o) 'Asynchronous