diff --git a/ChangeLog.md b/ChangeLog.md
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -1,6 +1,10 @@
 # Revision history for greskell
 
-## 1.2.0.0  -- 2020-12/29
+## 1.2.0.1  -- 2021-02-11
+
+* Confirm test with `doctest-0.18`.
+
+## 1.2.0.0  -- 2020-12-29
 
 * Add `Logic` module.
 
diff --git a/greskell.cabal b/greskell.cabal
--- a/greskell.cabal
+++ b/greskell.cabal
@@ -1,5 +1,5 @@
 name:                   greskell
-version:                1.2.0.0
+version:                1.2.0.1
 author:                 Toshio Ito <debug.ito@gmail.com>
 maintainer:             Toshio Ito <debug.ito@gmail.com>
 license:                BSD3
@@ -78,7 +78,7 @@
   ghc-options:          -Wall -fno-warn-unused-imports "-with-rtsopts=-M512m"
   main-is:              DocTest.hs
   build-depends:        base,
-                        doctest >=0.11 && <0.18,
+                        doctest >=0.11 && <0.19,
                         doctest-discover >=0.1.0.8 && <0.3