diff --git a/CHANGELOG.md b/CHANGELOG.md
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,7 @@
+2.6.1.1
+-------
+* Relaxed upper version bound for `transformers`.
+
 2.6.1.0
 -------
 * Updated OpenGL registry to r32258. Note that the major version was
diff --git a/OpenGLRaw.cabal b/OpenGLRaw.cabal
--- a/OpenGLRaw.cabal
+++ b/OpenGLRaw.cabal
@@ -1,5 +1,5 @@
 name: OpenGLRaw
-version: 2.6.1.0
+version: 2.6.1.1
 synopsis: A raw binding for the OpenGL graphics system
 description:
   OpenGLRaw is a raw Haskell binding for the OpenGL 4.5 graphics system and
@@ -607,7 +607,7 @@
     containers   >= 0.3     && < 0.6,
     half         >= 0.2.2.1 && < 0.3,
     text         >= 0.1     && < 1.3,
-    transformers >= 0.2     && < 0.5
+    transformers >= 0.2     && < 0.6
   default-language: Haskell2010
   ghc-options: -Wall
   other-extensions: CPP