diff --git a/Changelog.md b/Changelog.md
--- a/Changelog.md
+++ b/Changelog.md
@@ -1,3 +1,9 @@
+### 1.1.0
+
+- Use polymorphic return types in functions *terminateWorkerProcess*,
+  *restartWorkerProcess*, and *finalizeHTTPRequest* which allows throwing the
+  corresponding exceptions in any context.
+
 ### 1.0
 
 - The whole package was split into five separate sub-modules.
diff --git a/LICENSE b/LICENSE
--- a/LICENSE
+++ b/LICENSE
@@ -1,7 +1,7 @@
 The following license covers this documentation, and the source code, except
 where otherwise indicated.
 
-Copyright 2018-2022, Alexey Radkov. All rights reserved.
+Copyright 2018-2023, Alexey Radkov. All rights reserved.
 
 Redistribution and use in source and binary forms, with or without
 modification, are permitted provided that the following conditions are met:
diff --git a/NgxExport/Tools/System.hs b/NgxExport/Tools/System.hs
--- a/NgxExport/Tools/System.hs
+++ b/NgxExport/Tools/System.hs
@@ -1,7 +1,7 @@
 -----------------------------------------------------------------------------
 -- |
 -- Module      :  NgxExport.Tools.System
--- Copyright   :  (c) Alexey Radkov 2018-2022
+-- Copyright   :  (c) Alexey Radkov 2018-2023
 -- License     :  BSD-style
 --
 -- Maintainer  :  alexey.radkov@gmail.com
@@ -47,7 +47,7 @@
 -- Nginx master process shall /not/ spawn a new worker process thereafter. This
 -- function throws exception 'TerminateWorkerProcess', and therefore terminates
 -- the worker process effectively only from a Haskell service.
-terminateWorkerProcess :: String -> IO ()
+terminateWorkerProcess :: String -> IO a
 terminateWorkerProcess = throwIO . TerminateWorkerProcess
 
 -- | Restarts the Nginx worker process from a Haskell service.
@@ -56,7 +56,7 @@
 -- the current one. This function throws exception 'RestartWorkerProcess', and
 -- therefore terminates the worker process effectively only from a Haskell
 -- service.
-restartWorkerProcess :: String -> IO ()
+restartWorkerProcess :: String -> IO a
 restartWorkerProcess = throwIO . RestartWorkerProcess
 
 -- | Finalizes the current HTTP request from a Haskell asynchronous variable
@@ -65,7 +65,7 @@
 -- This function throws exception 'FinalizeHTTPRequest', and therefore
 -- terminates the HTTP request effectively only from a Haskell asynchronous
 -- variable handler.
-finalizeHTTPRequest :: Int -> Maybe String -> IO ()
+finalizeHTTPRequest :: Int -> Maybe String -> IO a
 finalizeHTTPRequest = (throwIO .) . FinalizeHTTPRequest
 
 -- | Checks that a generic exception is of type 'WorkerProcessIsExiting'.
diff --git a/NgxExport/Tools/TimeInterval.hs b/NgxExport/Tools/TimeInterval.hs
--- a/NgxExport/Tools/TimeInterval.hs
+++ b/NgxExport/Tools/TimeInterval.hs
@@ -36,12 +36,16 @@
 -- resolution timeouts.
 
 -- | Time intervals.
+--
+-- Note that /Unset/ is a zero time interval which is equal to 0 seconds,
+-- however it is expected to be used differently. In particular, to explicitly
+-- express an intention to unset the timeout.
 data TimeInterval = Hr Int          -- ^ Hours
                   | Min Int         -- ^ Minutes
                   | Sec Int         -- ^ Seconds
                   | HrMin Int Int   -- ^ Hours and minutes
                   | MinSec Int Int  -- ^ Minutes and seconds
-                  | Unset           -- ^ Zero time interval, equal to @Sec 0@
+                  | Unset           -- ^ Zero time interval
                   deriving (Generic, Lift, Read, Show)
 
 instance FromJSON TimeInterval
diff --git a/ngx-export-tools.cabal b/ngx-export-tools.cabal
--- a/ngx-export-tools.cabal
+++ b/ngx-export-tools.cabal
@@ -1,5 +1,5 @@
 name:                       ngx-export-tools
-version:                    1.0
+version:                    1.1.0
 synopsis:                   Extra tools for Nginx haskell module
 description:                Extra tools for
         <https://github.com/lyokha/nginx-haskell-module Nginx haskell module>.
@@ -10,7 +10,7 @@
 author:                     Alexey Radkov <alexey.radkov@gmail.com>
 maintainer:                 Alexey Radkov <alexey.radkov@gmail.com>
 stability:                  stable
-copyright:                  2018-2022 Alexey Radkov
+copyright:                  2018-2023 Alexey Radkov
 category:                   Network
 build-type:                 Simple
 cabal-version:              1.20